st n disinfect lect
TRANSCRIPT
بسم هللا الرحمن الرحيمbull
Sterilization and Disinfection
Dr Nadir Mehmood
Asstt Prof of Surgery
RMC
Learning ObjectivesAt the end of the discussion a student will be able to
bull Define terms in relation to topic
bull Classify methods of sterilization and disinfectives
bull Enumerate the merits of different methods
bull Indicate the choice of method for different instruments and procedures
bull Identify sequence followed in the CSSD
bull Identify categories of critical and noncritical items
WHY NEEDED
bull Microorganisms are ubiquitous
bull Since they cause contamination infection and decay it becomes necessary to remove or destroy them from materials or from areas
bull This is the object of sterilization
The process of sterilization is used
bull in microbiology for preventing contamination by extraneous organisms
bull in surgery for maintaining asepsis
bull in food and drug manufacture for ensuring safety from contaminating organisms and
bull in many other situations
The methods of sterilization employed depend on
bull the purpose for which it is carried out
bull the material which has to be sterilized and
bull the nature of the microorganisms that are to be removed or destroyed
Definition of termsbull Cleaning - the physical removal of organic
material or soil from objects is usually done by using water with or without detergents
bull Sterilization is the destruction of all forms of microbial life it is carried out in the hospital with steam under pressure liquid or gaseous chemicals or dry heat
bull Disinfection defined as the intermediate measures between physical cleaning and sterilization is carried out with pasteurization or chemical germicides
FUNCTIONS amp ACTIVITIES of CSSD
CSSD
Rinsing
cleaning
Drying
checking
sterilizationLabelling
Storage
Issue amp Distribution
Receipt
Various Agents In Sterilization
PHYSICAL AGENTS CHEMICAL AGENTS
SunlightAlcohols
Ethanol isopropyl
DryingAldehydes
Formaldehyde Glutaraldehyde
Dry heat
Hot air oven Incineration FlamingDyes
Moist heat
Boiling Pasteurization tyndallisation
Autoclaving
Halogens
Filtration Phenolic compounds
Radiation
Ionizing Non Ionizing
Gases
Ethylene oxide Formaldehyde beta
propiolactone(BPL)
Ultrasonic vibration Metallic salts and surface active agents
Physical Agents
SunlightbullDirect sunlight is a natural method of sterilization of water in tanks rivers and
lakes
bullDirect sunlight has an active germicidal effect due to the combined effect of
ultraviolet and heat rays
Dryingbull45 of the bacterial weight is due to water
bullTherefore drying in air has deleterious effect on many bacteria
bullThis is unreliable method spores are unaffected by drying
Dry heatFlaming
Inoculating loop or wire the tip of forceps are held in a Bunsen flame till they
become red hot
Incineration
This method is used to destroy contaminated cloth animal carcasses and pathological materials
Physical Agents cont
Hot air oven
This method is applicable to metals glassware and some heat-
resistant oils and waxes that are immiscible in water
Conditions
171ordmc for at least one hour
160ordmc for at least two hour
121ordmc for at least sixteen hour
Moist Heat
Flash autoclaves use 134degC for 3 minutes
Method Uses Comments
Water lt 100degc (Pasteurization) For sterilization of serum vaccines and body fluids
62degc for 15 min72degc for 30 secSpores are not destroyed
Water at 100degc For sterilization of glasswares metal and rubber items
Some spores are not destroyed
Arnold steamerStream at atmospheric pressure
For sterilization of culture media containing gelatin and sugar
Preserves properties of media
Autoclave Steam above atm pressure
For sterilization of culture media and laboratory materials
121degc at 15 psi for 15-20 minutesAlmost Kills all the bacteria and spores
Physical Agents cont
Filteration
Filtration helps to remove bacteria from large volumes of
fluid especially fluid containing heat-labile components such as
sera solution of sugars and antibiotics
A pore size of 02 m is effective because filters act not only
mechanically but by electrostatic adsorption of particles to their surface
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Sterilization and Disinfection
Dr Nadir Mehmood
Asstt Prof of Surgery
RMC
Learning ObjectivesAt the end of the discussion a student will be able to
bull Define terms in relation to topic
bull Classify methods of sterilization and disinfectives
bull Enumerate the merits of different methods
bull Indicate the choice of method for different instruments and procedures
bull Identify sequence followed in the CSSD
bull Identify categories of critical and noncritical items
WHY NEEDED
bull Microorganisms are ubiquitous
bull Since they cause contamination infection and decay it becomes necessary to remove or destroy them from materials or from areas
bull This is the object of sterilization
The process of sterilization is used
bull in microbiology for preventing contamination by extraneous organisms
bull in surgery for maintaining asepsis
bull in food and drug manufacture for ensuring safety from contaminating organisms and
bull in many other situations
The methods of sterilization employed depend on
bull the purpose for which it is carried out
bull the material which has to be sterilized and
bull the nature of the microorganisms that are to be removed or destroyed
Definition of termsbull Cleaning - the physical removal of organic
material or soil from objects is usually done by using water with or without detergents
bull Sterilization is the destruction of all forms of microbial life it is carried out in the hospital with steam under pressure liquid or gaseous chemicals or dry heat
bull Disinfection defined as the intermediate measures between physical cleaning and sterilization is carried out with pasteurization or chemical germicides
FUNCTIONS amp ACTIVITIES of CSSD
CSSD
Rinsing
cleaning
Drying
checking
sterilizationLabelling
Storage
Issue amp Distribution
Receipt
Various Agents In Sterilization
PHYSICAL AGENTS CHEMICAL AGENTS
SunlightAlcohols
Ethanol isopropyl
DryingAldehydes
Formaldehyde Glutaraldehyde
Dry heat
Hot air oven Incineration FlamingDyes
Moist heat
Boiling Pasteurization tyndallisation
Autoclaving
Halogens
Filtration Phenolic compounds
Radiation
Ionizing Non Ionizing
Gases
Ethylene oxide Formaldehyde beta
propiolactone(BPL)
Ultrasonic vibration Metallic salts and surface active agents
Physical Agents
SunlightbullDirect sunlight is a natural method of sterilization of water in tanks rivers and
lakes
bullDirect sunlight has an active germicidal effect due to the combined effect of
ultraviolet and heat rays
Dryingbull45 of the bacterial weight is due to water
bullTherefore drying in air has deleterious effect on many bacteria
bullThis is unreliable method spores are unaffected by drying
Dry heatFlaming
Inoculating loop or wire the tip of forceps are held in a Bunsen flame till they
become red hot
Incineration
This method is used to destroy contaminated cloth animal carcasses and pathological materials
Physical Agents cont
Hot air oven
This method is applicable to metals glassware and some heat-
resistant oils and waxes that are immiscible in water
Conditions
171ordmc for at least one hour
160ordmc for at least two hour
121ordmc for at least sixteen hour
Moist Heat
Flash autoclaves use 134degC for 3 minutes
Method Uses Comments
Water lt 100degc (Pasteurization) For sterilization of serum vaccines and body fluids
62degc for 15 min72degc for 30 secSpores are not destroyed
Water at 100degc For sterilization of glasswares metal and rubber items
Some spores are not destroyed
Arnold steamerStream at atmospheric pressure
For sterilization of culture media containing gelatin and sugar
Preserves properties of media
Autoclave Steam above atm pressure
For sterilization of culture media and laboratory materials
121degc at 15 psi for 15-20 minutesAlmost Kills all the bacteria and spores
Physical Agents cont
Filteration
Filtration helps to remove bacteria from large volumes of
fluid especially fluid containing heat-labile components such as
sera solution of sugars and antibiotics
A pore size of 02 m is effective because filters act not only
mechanically but by electrostatic adsorption of particles to their surface
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Learning ObjectivesAt the end of the discussion a student will be able to
bull Define terms in relation to topic
bull Classify methods of sterilization and disinfectives
bull Enumerate the merits of different methods
bull Indicate the choice of method for different instruments and procedures
bull Identify sequence followed in the CSSD
bull Identify categories of critical and noncritical items
WHY NEEDED
bull Microorganisms are ubiquitous
bull Since they cause contamination infection and decay it becomes necessary to remove or destroy them from materials or from areas
bull This is the object of sterilization
The process of sterilization is used
bull in microbiology for preventing contamination by extraneous organisms
bull in surgery for maintaining asepsis
bull in food and drug manufacture for ensuring safety from contaminating organisms and
bull in many other situations
The methods of sterilization employed depend on
bull the purpose for which it is carried out
bull the material which has to be sterilized and
bull the nature of the microorganisms that are to be removed or destroyed
Definition of termsbull Cleaning - the physical removal of organic
material or soil from objects is usually done by using water with or without detergents
bull Sterilization is the destruction of all forms of microbial life it is carried out in the hospital with steam under pressure liquid or gaseous chemicals or dry heat
bull Disinfection defined as the intermediate measures between physical cleaning and sterilization is carried out with pasteurization or chemical germicides
FUNCTIONS amp ACTIVITIES of CSSD
CSSD
Rinsing
cleaning
Drying
checking
sterilizationLabelling
Storage
Issue amp Distribution
Receipt
Various Agents In Sterilization
PHYSICAL AGENTS CHEMICAL AGENTS
SunlightAlcohols
Ethanol isopropyl
DryingAldehydes
Formaldehyde Glutaraldehyde
Dry heat
Hot air oven Incineration FlamingDyes
Moist heat
Boiling Pasteurization tyndallisation
Autoclaving
Halogens
Filtration Phenolic compounds
Radiation
Ionizing Non Ionizing
Gases
Ethylene oxide Formaldehyde beta
propiolactone(BPL)
Ultrasonic vibration Metallic salts and surface active agents
Physical Agents
SunlightbullDirect sunlight is a natural method of sterilization of water in tanks rivers and
lakes
bullDirect sunlight has an active germicidal effect due to the combined effect of
ultraviolet and heat rays
Dryingbull45 of the bacterial weight is due to water
bullTherefore drying in air has deleterious effect on many bacteria
bullThis is unreliable method spores are unaffected by drying
Dry heatFlaming
Inoculating loop or wire the tip of forceps are held in a Bunsen flame till they
become red hot
Incineration
This method is used to destroy contaminated cloth animal carcasses and pathological materials
Physical Agents cont
Hot air oven
This method is applicable to metals glassware and some heat-
resistant oils and waxes that are immiscible in water
Conditions
171ordmc for at least one hour
160ordmc for at least two hour
121ordmc for at least sixteen hour
Moist Heat
Flash autoclaves use 134degC for 3 minutes
Method Uses Comments
Water lt 100degc (Pasteurization) For sterilization of serum vaccines and body fluids
62degc for 15 min72degc for 30 secSpores are not destroyed
Water at 100degc For sterilization of glasswares metal and rubber items
Some spores are not destroyed
Arnold steamerStream at atmospheric pressure
For sterilization of culture media containing gelatin and sugar
Preserves properties of media
Autoclave Steam above atm pressure
For sterilization of culture media and laboratory materials
121degc at 15 psi for 15-20 minutesAlmost Kills all the bacteria and spores
Physical Agents cont
Filteration
Filtration helps to remove bacteria from large volumes of
fluid especially fluid containing heat-labile components such as
sera solution of sugars and antibiotics
A pore size of 02 m is effective because filters act not only
mechanically but by electrostatic adsorption of particles to their surface
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
WHY NEEDED
bull Microorganisms are ubiquitous
bull Since they cause contamination infection and decay it becomes necessary to remove or destroy them from materials or from areas
bull This is the object of sterilization
The process of sterilization is used
bull in microbiology for preventing contamination by extraneous organisms
bull in surgery for maintaining asepsis
bull in food and drug manufacture for ensuring safety from contaminating organisms and
bull in many other situations
The methods of sterilization employed depend on
bull the purpose for which it is carried out
bull the material which has to be sterilized and
bull the nature of the microorganisms that are to be removed or destroyed
Definition of termsbull Cleaning - the physical removal of organic
material or soil from objects is usually done by using water with or without detergents
bull Sterilization is the destruction of all forms of microbial life it is carried out in the hospital with steam under pressure liquid or gaseous chemicals or dry heat
bull Disinfection defined as the intermediate measures between physical cleaning and sterilization is carried out with pasteurization or chemical germicides
FUNCTIONS amp ACTIVITIES of CSSD
CSSD
Rinsing
cleaning
Drying
checking
sterilizationLabelling
Storage
Issue amp Distribution
Receipt
Various Agents In Sterilization
PHYSICAL AGENTS CHEMICAL AGENTS
SunlightAlcohols
Ethanol isopropyl
DryingAldehydes
Formaldehyde Glutaraldehyde
Dry heat
Hot air oven Incineration FlamingDyes
Moist heat
Boiling Pasteurization tyndallisation
Autoclaving
Halogens
Filtration Phenolic compounds
Radiation
Ionizing Non Ionizing
Gases
Ethylene oxide Formaldehyde beta
propiolactone(BPL)
Ultrasonic vibration Metallic salts and surface active agents
Physical Agents
SunlightbullDirect sunlight is a natural method of sterilization of water in tanks rivers and
lakes
bullDirect sunlight has an active germicidal effect due to the combined effect of
ultraviolet and heat rays
Dryingbull45 of the bacterial weight is due to water
bullTherefore drying in air has deleterious effect on many bacteria
bullThis is unreliable method spores are unaffected by drying
Dry heatFlaming
Inoculating loop or wire the tip of forceps are held in a Bunsen flame till they
become red hot
Incineration
This method is used to destroy contaminated cloth animal carcasses and pathological materials
Physical Agents cont
Hot air oven
This method is applicable to metals glassware and some heat-
resistant oils and waxes that are immiscible in water
Conditions
171ordmc for at least one hour
160ordmc for at least two hour
121ordmc for at least sixteen hour
Moist Heat
Flash autoclaves use 134degC for 3 minutes
Method Uses Comments
Water lt 100degc (Pasteurization) For sterilization of serum vaccines and body fluids
62degc for 15 min72degc for 30 secSpores are not destroyed
Water at 100degc For sterilization of glasswares metal and rubber items
Some spores are not destroyed
Arnold steamerStream at atmospheric pressure
For sterilization of culture media containing gelatin and sugar
Preserves properties of media
Autoclave Steam above atm pressure
For sterilization of culture media and laboratory materials
121degc at 15 psi for 15-20 minutesAlmost Kills all the bacteria and spores
Physical Agents cont
Filteration
Filtration helps to remove bacteria from large volumes of
fluid especially fluid containing heat-labile components such as
sera solution of sugars and antibiotics
A pore size of 02 m is effective because filters act not only
mechanically but by electrostatic adsorption of particles to their surface
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
The process of sterilization is used
bull in microbiology for preventing contamination by extraneous organisms
bull in surgery for maintaining asepsis
bull in food and drug manufacture for ensuring safety from contaminating organisms and
bull in many other situations
The methods of sterilization employed depend on
bull the purpose for which it is carried out
bull the material which has to be sterilized and
bull the nature of the microorganisms that are to be removed or destroyed
Definition of termsbull Cleaning - the physical removal of organic
material or soil from objects is usually done by using water with or without detergents
bull Sterilization is the destruction of all forms of microbial life it is carried out in the hospital with steam under pressure liquid or gaseous chemicals or dry heat
bull Disinfection defined as the intermediate measures between physical cleaning and sterilization is carried out with pasteurization or chemical germicides
FUNCTIONS amp ACTIVITIES of CSSD
CSSD
Rinsing
cleaning
Drying
checking
sterilizationLabelling
Storage
Issue amp Distribution
Receipt
Various Agents In Sterilization
PHYSICAL AGENTS CHEMICAL AGENTS
SunlightAlcohols
Ethanol isopropyl
DryingAldehydes
Formaldehyde Glutaraldehyde
Dry heat
Hot air oven Incineration FlamingDyes
Moist heat
Boiling Pasteurization tyndallisation
Autoclaving
Halogens
Filtration Phenolic compounds
Radiation
Ionizing Non Ionizing
Gases
Ethylene oxide Formaldehyde beta
propiolactone(BPL)
Ultrasonic vibration Metallic salts and surface active agents
Physical Agents
SunlightbullDirect sunlight is a natural method of sterilization of water in tanks rivers and
lakes
bullDirect sunlight has an active germicidal effect due to the combined effect of
ultraviolet and heat rays
Dryingbull45 of the bacterial weight is due to water
bullTherefore drying in air has deleterious effect on many bacteria
bullThis is unreliable method spores are unaffected by drying
Dry heatFlaming
Inoculating loop or wire the tip of forceps are held in a Bunsen flame till they
become red hot
Incineration
This method is used to destroy contaminated cloth animal carcasses and pathological materials
Physical Agents cont
Hot air oven
This method is applicable to metals glassware and some heat-
resistant oils and waxes that are immiscible in water
Conditions
171ordmc for at least one hour
160ordmc for at least two hour
121ordmc for at least sixteen hour
Moist Heat
Flash autoclaves use 134degC for 3 minutes
Method Uses Comments
Water lt 100degc (Pasteurization) For sterilization of serum vaccines and body fluids
62degc for 15 min72degc for 30 secSpores are not destroyed
Water at 100degc For sterilization of glasswares metal and rubber items
Some spores are not destroyed
Arnold steamerStream at atmospheric pressure
For sterilization of culture media containing gelatin and sugar
Preserves properties of media
Autoclave Steam above atm pressure
For sterilization of culture media and laboratory materials
121degc at 15 psi for 15-20 minutesAlmost Kills all the bacteria and spores
Physical Agents cont
Filteration
Filtration helps to remove bacteria from large volumes of
fluid especially fluid containing heat-labile components such as
sera solution of sugars and antibiotics
A pore size of 02 m is effective because filters act not only
mechanically but by electrostatic adsorption of particles to their surface
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Definition of termsbull Cleaning - the physical removal of organic
material or soil from objects is usually done by using water with or without detergents
bull Sterilization is the destruction of all forms of microbial life it is carried out in the hospital with steam under pressure liquid or gaseous chemicals or dry heat
bull Disinfection defined as the intermediate measures between physical cleaning and sterilization is carried out with pasteurization or chemical germicides
FUNCTIONS amp ACTIVITIES of CSSD
CSSD
Rinsing
cleaning
Drying
checking
sterilizationLabelling
Storage
Issue amp Distribution
Receipt
Various Agents In Sterilization
PHYSICAL AGENTS CHEMICAL AGENTS
SunlightAlcohols
Ethanol isopropyl
DryingAldehydes
Formaldehyde Glutaraldehyde
Dry heat
Hot air oven Incineration FlamingDyes
Moist heat
Boiling Pasteurization tyndallisation
Autoclaving
Halogens
Filtration Phenolic compounds
Radiation
Ionizing Non Ionizing
Gases
Ethylene oxide Formaldehyde beta
propiolactone(BPL)
Ultrasonic vibration Metallic salts and surface active agents
Physical Agents
SunlightbullDirect sunlight is a natural method of sterilization of water in tanks rivers and
lakes
bullDirect sunlight has an active germicidal effect due to the combined effect of
ultraviolet and heat rays
Dryingbull45 of the bacterial weight is due to water
bullTherefore drying in air has deleterious effect on many bacteria
bullThis is unreliable method spores are unaffected by drying
Dry heatFlaming
Inoculating loop or wire the tip of forceps are held in a Bunsen flame till they
become red hot
Incineration
This method is used to destroy contaminated cloth animal carcasses and pathological materials
Physical Agents cont
Hot air oven
This method is applicable to metals glassware and some heat-
resistant oils and waxes that are immiscible in water
Conditions
171ordmc for at least one hour
160ordmc for at least two hour
121ordmc for at least sixteen hour
Moist Heat
Flash autoclaves use 134degC for 3 minutes
Method Uses Comments
Water lt 100degc (Pasteurization) For sterilization of serum vaccines and body fluids
62degc for 15 min72degc for 30 secSpores are not destroyed
Water at 100degc For sterilization of glasswares metal and rubber items
Some spores are not destroyed
Arnold steamerStream at atmospheric pressure
For sterilization of culture media containing gelatin and sugar
Preserves properties of media
Autoclave Steam above atm pressure
For sterilization of culture media and laboratory materials
121degc at 15 psi for 15-20 minutesAlmost Kills all the bacteria and spores
Physical Agents cont
Filteration
Filtration helps to remove bacteria from large volumes of
fluid especially fluid containing heat-labile components such as
sera solution of sugars and antibiotics
A pore size of 02 m is effective because filters act not only
mechanically but by electrostatic adsorption of particles to their surface
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
FUNCTIONS amp ACTIVITIES of CSSD
CSSD
Rinsing
cleaning
Drying
checking
sterilizationLabelling
Storage
Issue amp Distribution
Receipt
Various Agents In Sterilization
PHYSICAL AGENTS CHEMICAL AGENTS
SunlightAlcohols
Ethanol isopropyl
DryingAldehydes
Formaldehyde Glutaraldehyde
Dry heat
Hot air oven Incineration FlamingDyes
Moist heat
Boiling Pasteurization tyndallisation
Autoclaving
Halogens
Filtration Phenolic compounds
Radiation
Ionizing Non Ionizing
Gases
Ethylene oxide Formaldehyde beta
propiolactone(BPL)
Ultrasonic vibration Metallic salts and surface active agents
Physical Agents
SunlightbullDirect sunlight is a natural method of sterilization of water in tanks rivers and
lakes
bullDirect sunlight has an active germicidal effect due to the combined effect of
ultraviolet and heat rays
Dryingbull45 of the bacterial weight is due to water
bullTherefore drying in air has deleterious effect on many bacteria
bullThis is unreliable method spores are unaffected by drying
Dry heatFlaming
Inoculating loop or wire the tip of forceps are held in a Bunsen flame till they
become red hot
Incineration
This method is used to destroy contaminated cloth animal carcasses and pathological materials
Physical Agents cont
Hot air oven
This method is applicable to metals glassware and some heat-
resistant oils and waxes that are immiscible in water
Conditions
171ordmc for at least one hour
160ordmc for at least two hour
121ordmc for at least sixteen hour
Moist Heat
Flash autoclaves use 134degC for 3 minutes
Method Uses Comments
Water lt 100degc (Pasteurization) For sterilization of serum vaccines and body fluids
62degc for 15 min72degc for 30 secSpores are not destroyed
Water at 100degc For sterilization of glasswares metal and rubber items
Some spores are not destroyed
Arnold steamerStream at atmospheric pressure
For sterilization of culture media containing gelatin and sugar
Preserves properties of media
Autoclave Steam above atm pressure
For sterilization of culture media and laboratory materials
121degc at 15 psi for 15-20 minutesAlmost Kills all the bacteria and spores
Physical Agents cont
Filteration
Filtration helps to remove bacteria from large volumes of
fluid especially fluid containing heat-labile components such as
sera solution of sugars and antibiotics
A pore size of 02 m is effective because filters act not only
mechanically but by electrostatic adsorption of particles to their surface
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Various Agents In Sterilization
PHYSICAL AGENTS CHEMICAL AGENTS
SunlightAlcohols
Ethanol isopropyl
DryingAldehydes
Formaldehyde Glutaraldehyde
Dry heat
Hot air oven Incineration FlamingDyes
Moist heat
Boiling Pasteurization tyndallisation
Autoclaving
Halogens
Filtration Phenolic compounds
Radiation
Ionizing Non Ionizing
Gases
Ethylene oxide Formaldehyde beta
propiolactone(BPL)
Ultrasonic vibration Metallic salts and surface active agents
Physical Agents
SunlightbullDirect sunlight is a natural method of sterilization of water in tanks rivers and
lakes
bullDirect sunlight has an active germicidal effect due to the combined effect of
ultraviolet and heat rays
Dryingbull45 of the bacterial weight is due to water
bullTherefore drying in air has deleterious effect on many bacteria
bullThis is unreliable method spores are unaffected by drying
Dry heatFlaming
Inoculating loop or wire the tip of forceps are held in a Bunsen flame till they
become red hot
Incineration
This method is used to destroy contaminated cloth animal carcasses and pathological materials
Physical Agents cont
Hot air oven
This method is applicable to metals glassware and some heat-
resistant oils and waxes that are immiscible in water
Conditions
171ordmc for at least one hour
160ordmc for at least two hour
121ordmc for at least sixteen hour
Moist Heat
Flash autoclaves use 134degC for 3 minutes
Method Uses Comments
Water lt 100degc (Pasteurization) For sterilization of serum vaccines and body fluids
62degc for 15 min72degc for 30 secSpores are not destroyed
Water at 100degc For sterilization of glasswares metal and rubber items
Some spores are not destroyed
Arnold steamerStream at atmospheric pressure
For sterilization of culture media containing gelatin and sugar
Preserves properties of media
Autoclave Steam above atm pressure
For sterilization of culture media and laboratory materials
121degc at 15 psi for 15-20 minutesAlmost Kills all the bacteria and spores
Physical Agents cont
Filteration
Filtration helps to remove bacteria from large volumes of
fluid especially fluid containing heat-labile components such as
sera solution of sugars and antibiotics
A pore size of 02 m is effective because filters act not only
mechanically but by electrostatic adsorption of particles to their surface
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Physical Agents
SunlightbullDirect sunlight is a natural method of sterilization of water in tanks rivers and
lakes
bullDirect sunlight has an active germicidal effect due to the combined effect of
ultraviolet and heat rays
Dryingbull45 of the bacterial weight is due to water
bullTherefore drying in air has deleterious effect on many bacteria
bullThis is unreliable method spores are unaffected by drying
Dry heatFlaming
Inoculating loop or wire the tip of forceps are held in a Bunsen flame till they
become red hot
Incineration
This method is used to destroy contaminated cloth animal carcasses and pathological materials
Physical Agents cont
Hot air oven
This method is applicable to metals glassware and some heat-
resistant oils and waxes that are immiscible in water
Conditions
171ordmc for at least one hour
160ordmc for at least two hour
121ordmc for at least sixteen hour
Moist Heat
Flash autoclaves use 134degC for 3 minutes
Method Uses Comments
Water lt 100degc (Pasteurization) For sterilization of serum vaccines and body fluids
62degc for 15 min72degc for 30 secSpores are not destroyed
Water at 100degc For sterilization of glasswares metal and rubber items
Some spores are not destroyed
Arnold steamerStream at atmospheric pressure
For sterilization of culture media containing gelatin and sugar
Preserves properties of media
Autoclave Steam above atm pressure
For sterilization of culture media and laboratory materials
121degc at 15 psi for 15-20 minutesAlmost Kills all the bacteria and spores
Physical Agents cont
Filteration
Filtration helps to remove bacteria from large volumes of
fluid especially fluid containing heat-labile components such as
sera solution of sugars and antibiotics
A pore size of 02 m is effective because filters act not only
mechanically but by electrostatic adsorption of particles to their surface
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Physical Agents cont
Hot air oven
This method is applicable to metals glassware and some heat-
resistant oils and waxes that are immiscible in water
Conditions
171ordmc for at least one hour
160ordmc for at least two hour
121ordmc for at least sixteen hour
Moist Heat
Flash autoclaves use 134degC for 3 minutes
Method Uses Comments
Water lt 100degc (Pasteurization) For sterilization of serum vaccines and body fluids
62degc for 15 min72degc for 30 secSpores are not destroyed
Water at 100degc For sterilization of glasswares metal and rubber items
Some spores are not destroyed
Arnold steamerStream at atmospheric pressure
For sterilization of culture media containing gelatin and sugar
Preserves properties of media
Autoclave Steam above atm pressure
For sterilization of culture media and laboratory materials
121degc at 15 psi for 15-20 minutesAlmost Kills all the bacteria and spores
Physical Agents cont
Filteration
Filtration helps to remove bacteria from large volumes of
fluid especially fluid containing heat-labile components such as
sera solution of sugars and antibiotics
A pore size of 02 m is effective because filters act not only
mechanically but by electrostatic adsorption of particles to their surface
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Physical Agents cont
Filteration
Filtration helps to remove bacteria from large volumes of
fluid especially fluid containing heat-labile components such as
sera solution of sugars and antibiotics
A pore size of 02 m is effective because filters act not only
mechanically but by electrostatic adsorption of particles to their surface
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Physical Agents cont
RADIATION
Non Ionisizing radiation
Types Produced by Mode of action Uses Comments
Low energy
(Infrared and
ultraviolet rays)
UV lamps DNA damage Infrared rays
Sterilization of prepacked
items such as syringes
and catheters
Ultraviolet rays
Used for disinfecting
operation threatres and
laboratories
Use of UV light
is limited by
penetration and
hazardous
Ionisizing radiation
High energy
ionizing type
(Gamma rays and
high energy
electrons such as
X-rays and
cosmic rays)
Cobalt-60
based
instruments
DNA damage For the sterilization of
antibiotics hormones
and other prepacked
disposable items such
as catheters gloves
syringes infusion sets
oils animal feeds etc
They are
expensive
They are very
effective due to
high penetrative
power
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Physical Agents cont
Ultrasonic and sonic vibration
They have the property to disrupt the cells but the results have been variable
Gram negative rods are more sensitive to ultrasonic vibration whereas Gram
positive cocci spores of fungi and bacteria are resistant to the vibration
Ultrasonic devices are used in dental
However most sonic machines are not reliable for routine use
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Chemical Agents cont
Properties of Ideal antiseptics or disinfectants should
Effective against all microorganisms and have a wide spectrum of
activity
Have speedy action
Be effective in presence of organic matter
Be effective in varying pH(acidic and alkaline medium)
Be stable
Also compatible with other antiseptics and disinfectants
Have high penetrating power
Not corrode metals
Not cause local irritation or sensitization
Not interfere with healing
Not be toxic if absorbed into circulationBe cheap and safe
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
The level of disinfection achieved depends on several factors
bull contact time
bull temperature
bull type and concentration of the active ingredients of the chemical germicide
bull the nature of the microbial contamination
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Mechanisms of action of antiseptic and disinfectants
bull Oxidation of bacterial protoplasm
ndash Potassium permagnate H202 Halogens
bull Co-agulation (denaturation) of bacterial proteins amp disrupt cell membrane
ndash Phenols chlorhexidine alcohols aldehydes
bull Detergent like action uarr permeability of bacterial cell membrane
ndash Cetrimide soaps
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Types of disinfectionbull High-level disinfection can be expected to
destroy all microorganisms with the exception of large numbers of bacterial spores
bull Intermediate disinfection inactivates Mycobacterium tuberculosis vegetative bacteria most viruses and most fungi does not necessarily kill bacterial spores
bull Low-level disinfection can kill most bacteria some viruses and some fungi cannot be relied on to kill resistant microorganisms such as tubercle bacilli or bacterial spores
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Medical devices equipment and surgical materials are divided into three general categories based on the potential risk of
infection involved in their use
critical items
semicritical items
noncritical items
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Critical items
bull Critical items are instruments or objects that are introduced directly into the bloodstream or into other normally sterile areas of the body
Examples of critical items are surgical instruments cardiac catheters implants pertinent components of the heart-lung oxygenator and the blood compartment of a hemodialyzer
Sterility at the time of use is required for these items consequently one of several accepted sterilization procedures is generally recommended
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Semicritical itemsbull These items come in contact with intact mucous membranes
but they do not ordinarily penetrate body surfaces
Examples are noninvasive flexible and rigid fiberoptic endoscopes endotracheal tubes anesthesia breathing circuits and cystoscopes
Sterilization is not absolutely essential at a minimum a high-level disinfection procedure that can be expected to destroy vegetative microorganisms most fungal spores tubercle bacilli and small nonlipid viruses is recommended In most cases meticulous physical cleaning followed by an appropriate high-level disinfection treatment gives the user a reasonable degree of assurance that the items are free of pathogens
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Noncritical items
bull Noncritical items are those that either do not ordinarily touch the patient or touch only intact skin
Such items include crutches bedboards blood pressure cuffs and a variety of other medical accessories
These items rarely if ever transmit disease Consequently washing with a detergent may be sufficient
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
bull Items must be thoroughly cleaned before processing because organic material (eg blood and proteins) may contain high concentrations of microorganisms Also such organic material may inactivate chemical germicides and protect microorganisms from the disinfection or sterilization process
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
For noncritical itemscleaning can consist only of
1) washing with a detergent or a disinfectant-detergent
2) rinsing
3) thorough drying
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Steam sterilization
bull Steam sterilization is the most inexpensive and effective method for sterilization
bull Steam sterilization is unsuitable for processing plastics with low melting points powders or anhydrous oils
bull Items that are to be sterilized but not used immediately need to be wrapped for storage
bull Sterility can be maintained in storage for various lengths of time depending on the type of wrapping material the conditions of storage and the integrity of the package
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Monitoring of steam sterilization processes
bull to check the highest temperature that is reached during sterilization and the length of time that this temperature is maintained
bull heat- and steam-sensitive chemical indicators can be used on the outside of each pack
bull a large pack might have a chemical indicator both on the outside and the inside to verify that steam has penetrated the pack
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Microbiological monitoring
Microbiological monitoring of steam sterilizers is recommended at least once a week with commercial preparations of spores of Bacillus stearothermophilus (a microorganism having spores that are particularly resistant to moist heat thus assuring a wide margin of safety)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Ethylene oxide gas sterilization
bull It is a more complex and expensive process than steam sterilization
bull It is usually restricted to objects that might be damaged by heat or excessive moisture
bull Before sterilization objects also need to be cleaned thoroughly and wrapped in a material that allows the gas to penetrate
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
bull Because ethylene oxide gas is toxic precautions (eg local exhaust ventilation) should be taken to protect personnel All objects processed by gas sterilization also need special aeration according to manufacturers recommendations before use to remove toxic residues of ethylene oxide
bull Chemical indicators need to be used with each package to show that it has been exposed to the gas sterilization process
bull Moreover it is recommended that gas sterilizers be checked at least once a week with commercial preparations of spores usually Bacillus subtilis
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
bull Powders and anhydrous oils can be sterilized by dry heat Microbiological monitoring of dry heat sterilizers usually provides a wide margin of safety for dry heat sterilization
bull Liquid chemicals can be used for sterilization and disinfection when steam gas or dry heat sterilization is not indicated or available
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Chloroxylenol (Dettol)
bull Phenol derivative
bull Does not co-agulate proteins
bull Non corrosiveNon irritating to skin
bull Commercial 48 solution used for surgical antisepsis
bull Skin cream and soap 08
bull Mouth wash 1
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Oxidizing agents
bull Potassium permagnate
ndash Purple crystals highly water soluble liberates oxygen which oxidizes bacterial protoplasm
ndash Used for gargling irrigating wounds urethra (condy`s lotion diluted solution of 14000 to 110000 )
ndash High conc cause burns
ndash It is also used to disinfect water in ponds
ndash Stomach wash in alkaloidal poisoning
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Oxidizing agents
Hydrogen Peroxide
ndash liberates nascent oxygen which oxidizes necrotic matter amp bacteria
ndash Helps in loosening amp removing slough ear wax etc
Benzoyl Peroxide
ndash Widely used drug for acne
ndash liberates O2 in presence of water which kills bacteria specially anaerobes
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Halogens
bull Iodine
bull Iodophores
bull Chlorine
bull Chlorophores
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Iodine
bull Rapidly acting broad spectrum (bacteria fungivirus)
bull Acts by iodinating and oxidizing microbial protoplasm
bull Used for cuts degerming skin beforesurgery
bull Adverse effect cause burns amp blisters
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Iodophores
bull Known as povidine iodine
bull Non toxic non staining prolonged action
bull Used on boils furunculosis burns ulcers tinea surgical srub disinfecting surgical instruments non specific vaginitis
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Chlorine
bull potent germicide Kills pathogens in 30 sec used to disinfect urban water supplies
bull 01 to 025 ppm
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Cholorophores
(1) Chlorinated lime (bleaching powder)
ndash obtained by action of chlorine on lime
ndash used to disinfect drinking water
(2) Sodium hypochlorite
ndash Powerful disinfectant used in dairies for milk cans
ndash Too Irritant to be used as antiseptic
ndash Root canal therapy in dentisry
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Biguanides
Chlorhexidine (Savlon)
ndash Acts by disrupting bacterial cell membrane amp denaturation of bacterial proteins
ndash Non irritant more active against gram +vebacteria
ndash Used in for surgical scrub neonatal bath mouth wash amp general skin antiseptic
ndash Most widely used antiseptic in dentisry 012-02 oral rinse or 05 -1 tooth paste
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Quarternary ammonium antisepticscetrimide
bull Detergents Cidal to bacteria fungi amp viruses
bull Act by altering permeability of cell membrane
bull Efficiently remove dirt and grease
bull Widely used as antiseptics amp disinfectants for
surgical instruments gloves etc
bull Combined with chlorhexidine (savlon)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Soaps
bull Anionic detergents
bull Weak antiseptics with cleansing action
bull Washing with soap and warm water one of the most effective methods of preventing disease transmission
bull Affect only Gm+ bacteria
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Dyes
Gentian violet
ndash Active against bacteria (gram + ve) fungi
ndash Used on chronic ulcers furunculosis bed sores ring worms
Acriflavine
ndash Active against gram +ve bacteria amp gonocci
ndash suitable for chronic ulcers amp wounds
ndash Do not retard healing non irritant
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
Microbial Characteristics and Microbial Control
Figure 711
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)
No Disinfectant is substitute for the following Procedures
bull 1048766 Hand washing (hand hygiene)bull 1048766 The use of personal protective equipment (eg
gloves) when handling blood bodybull substances excretions and secretionsbull 1048766 Appropriate handling of patient care equipment
and soiled linenbull 1048766 The prevention of needle sticksharp injuriesbull 1048766 Environmental cleaningbull 1048766 Appropriate handling of waste andbull 1048766 Taking care of yourself (eg immunization)