Infection Control

By

Dr. Amer Hasanien &

Dr. Ali Saleh

Related Terms◼ Normal resident flora (bacteria) the collective

vegetation (نمو) in a given area, yet produce infection in another.

◼ Infection : invasion of body tissue by microorganisms (infectious agents) and their growth there.

◼ Disease : a detectable alteration in normal tissue function

◼ Virulence (Pathogenicity): the ability of microorganism to produce disease.

◼ Opportunistic pathogen: causes disease only in a susceptible individuals.

◼ WHO & CDC (Centre for Disease Control)

Asepsis◼ Asepsis is the freedom from disease-causing

microorganisms and its spores Medical asepsis: all practices intended to confine a

specific microorganism to a specific area, limiting the number of microorganisms, growth and transmission.

- Clean objects: absence of almost all microorganisms.

- Dirty (Soiled, Contaminated) : have microorganisms, some of which capable of causing infection.

Surgical asepsis (Sterile Technique): practices that keep area or object free from all microorganisms; destroy all microorganisms and spores.

◼ Sepsis : the state of infection, may includes septicemia and septic shock.

Microorganisms causing infections

◼ Bacteria (Staphs, Streptococci)

◼ Viruses (Hepatitis, Herpes..)

◼ Fungi (Candida albicans)

◼ Parasites [طفيليات] (Malaria) (mites [العث], fleas .([القرادة] ticks ,[البراغيث]

Types of infections◼ Contamination: the presence of microorganisms on

certain areas of the body or environment

◼ Colonization : microorganisms become resident flora, they may grow and multiply, but do not cause disease.

◼ Local Infection : infection limited to specific area of the body.

◼ Systemic Infection : spread to different parts of the body.

◼ Bacteremia : Blood culture reveals microorganisms

◼ Septicemia : when bacteremia results in systemic infection.

◼ Acute infection : sudden and in short time.

◼ Chronic infection : slow and in very long period.

Blood culture bottles

Nosocomial Infections

◼ Infections associated with delivery of health care services in a health care facility (during stay or after discharge)

◼ Most common nosocomial infections sites are urinary tract, respiratory tract, bloodstream, and wounds.

◼ It may originates as Endogenous (clients themselves) or Exogenous (hospital environment and hospital personnel) .

◼ Iatrogenic infections are direct result of diagnostic or therapeutic procedures (e.g. IV insertion).

Chain of Infection

Method of transmission

1. Direct transmission : droplet, touch, bite, sexual intercourse.

2. Indirect transmission:

- Vehicle-borne: substance that serves as an intermediate means to transport an infectious agent (surgical instruments, toys, soiled clothes)

- Vector-borne: is an animal or flying insect

3. Airborne transmission: involve droplets or dust (Tuberculosis by droplet nuclei).

Body Defense against infection

(Susceptible Host)Nonspecific Defenses :

◼ anatomic & Physiologic Barriers: e.g. skin and mucous membranes, nasal passages, saliva, tears, acidity of the stomach

◼ inflammatory response : Inflammation: is local and nonspecific defensive response

of the tissues to an injurious or infectious agent. It has 5 signs: pain, swelling, redness, heat, and impaired function of the part.

Injurious agents can be physical, chemical, or microorganism.

Three stages of inflammatory response: vascular and cellular response, exudates production, and reparative phase

Body Defense against infection

Specific Defenses :

◼ antibody-mediated

Active immunity: Host produces antibodies in

response to natural antigens (e.g. infectious

microorganisms) or artificial antigens (vaccines)

Passive immunity: Host receives natural (e.g. nursing

mother) or artificial antibodies (immune serum)

produced from another source.

◼ cell-mediated: by activating T cell system (cell

mediated immunity is lost in HIV)

FACTORS INFLUENCE

SUSCEPTIBILITY OF THE HOST

◼ Age: newborns and elders have reduced defenses against infections.

◼ Heredity

◼ Physical and Emotional Stressors: ↑ blood cortisone → ↓ anti-inflammatory responses, depletes energy stores, exhaustion, ↓ resistance to infections.

◼ Nutritional status: e.g. antibodies are protiens.

◼ Medical therapy: e.g. radiation, invasive procedures.

◼ Certain medication: e.g. antineoplastic medications may depress bone marrow function.

◼ Any disease that lessens the body’s defenses against infection.

Nursing Diagnoses

◼ Risk for infection

◼ Potential complication of infection: fever

◼ Impaired physical mobility

◼ Imbalanced nutrition: less than body requirements

◼ Acute pain

◼ Anxiety

Prevention and Treatment of

Infection

Preventing Nosocomial Infections

◼ Proper hand hygiene techniques

◼ Environmental controls

◼ Sterile technique when warranted

◼ Identification and management of clients

at risk

Prevention and Treatment of

Infection

Hand Hygiene Before and after eating

After using toilets, bedpan

Contact with body substance (sputum, drainage, wound exudates).

Before and after giving care

◼ For routine care, wash hands with soaps under stream water for at least 20 sec. (WHO). OR

◼ Using of alcohol-based antiseptic hand rubs (rinses, gels, or foams) for about 20-30 sec. (CDC).

Prevention and Treatment of

Infection

◼ Use antimicrobial agent in:

Multiple resistant bacteria (e.g., Methicillin-

Resistant Staphylococcus aureus (MRSA), Vancomycin-Resistant Enterococci (VRE))

Invasive procedures

Special care units such as ICU’S

Immunocompromised clients.

◼ Frequent use of soap or alcohol antiseptic agents may induce: dryness, contact dermatitis → lotions, moisturizers

Prevention and Treatment of

Infection

Supporting Defenses of a Susceptible Host

◼ Hygiene (bathing and shampooing)

◼ Nutrition (well-balanced diet) to maintain healthy tissues.

◼ Fluids

◼ Rest and sleep

◼ Stress

◼ Immunization

Prevention and Treatment of

Infection

Disinfecting and Sterilizing

◼ Antiseptics: agents that inhibit the growth of some microorganisms.

◼ Disinfectants: agents that destroy pathogens other than spores

Disinfecting

◼ Using chemical preparations such as phenol or iodine compounds.

◼ Used on inanimate objects as it is toxic to tissues.

◼ More concentrated than antiseptics.

◼ Bactericidal (destroy bacteria) and bacteriostatic (prevent growth and reproduction of some bacteria) agents.

Prevention and Treatment of

Infection

When using disinfectants consider:

◼ Type and number of organisms

◼ Concentration and duration of contact of disinfectant

◼ Presence of soap

◼ Presence of organic materials such as blood

◼ The surface area to be treated

Prevention and Treatment of

InfectionSterilization

◼ The process of destroying all microorganisms, including spores and viruses. Methods of sterilization:

◼ Moist heat: steam under pressure (autoclaving)

◼ Gas: Ethylene oxide gas (interferes with metabolism of microorganisms) for sensitive objects and more penetration. But toxic to humans

◼ Boiling water: in home. Spores and some viruses are not

killed. 100 ˚ c/ 15 min.

◼ Radiation: using ionizing (alpha, beta, and X-Rays) and non-ionizing radiation (UV rays). Effective for items difficult to sterilize. It is very expensive.

autoclaving

Isolation Precautions

◼ Measures designed to prevent spread of infections or potentially infectious microorganisms to health personnel, clients and visitors.

◼ Category-specific Isolation Precautions: Strict isolation, Contact isolation, Respiratory isolation, Tuberculosis isolation, Enteric precautions, Drainage/secretions precautions, Blood/body fluid precautions.

◼ Disease-specific Isolation Precautions: Delineate practices for control of specific diseases. Use of private rooms with special ventilation

Cohorting clients infected with the same organism

Gowning to prevent gross soiling of clothes

Gown

Patient Health care provider

Isolation Precautions

Universal Precautions (UP)

◼ Used with all clients

◼ Decrease the risk of transmitting unidentified

pathogens

◼ Obstruct the spread of bloodborne pathogens

(hepatitis B and C viruses and HIV)

◼ Used in conjunction with disease-specific or

category-specific precautions

Isolation Precautions

Body Substance Isolation (BSI)

◼ Employs generic infection control precautions for all clients except for few diseases transmitted through air.

◼ Body substances include: Blood

Urine

Feces

Wound drainage

Oral secretions

Any other body product or tissue

Isolation Precautions

Standard Precautions

◼ Used in the care of all hospitalized persons regardless of their diagnosis or possible infection status

◼ Apply to Blood

All body fluids, secretions, and excretions except sweat (whether or not blood is present or visible)

Nonintact skin and mucous membranes

◼ Combine the major features of Universal and Body Substance Isolation

Standard Precautions

◼ Hand Hygiene Also after removing gloves

Using antimicrobial and antiseptic agents.

◼ Wearing clean gloves

◼ Wear mask, Eye protection, or a face shield.

◼ Wear clean gown

◼ Handle equipments carefully

◼ Handle, transport, and process linen appropriately.

◼ Prevent injuries from used scalpels, or other equipment, and place puncture resistant containers.

face shield puncture resistant

containers

Isolation Precautions

Transmission-based Precautions

◼ Used in addition to standard precautions

◼ For known or suspected infections that are spread in one of three ways: Airborne: droplet nuclei (< 5 microns)

Droplet: droplets (> 5 microns)

Contact

◼ May be used alone or in combination but always in addition to standard precautions

Micron (US): is an SI derived unit of length

equaling 1×10−6 of a metre

Transmission-based Precautions

Airborne Precautions:

◼ Private room, negative air pressure

◼ 2-same infected clients with same

microorganism.

◼ Respiratory devices (e.g. N95 for tuberculosis)

◼ NO entry of susceptible people ((rubella

(measles), varisella (chickenpox)).

◼ Limit patient’s movement (surgical mask).

N95 for tuberculosis

Transmission-based Precautions

Droplet Precaution

◼ Used in droplet-transmitted infections (diphtheria, pneumonia, pertussis, mumps)

◼ Private room

◼ 2-same infected clients.

◼ Mask

◼ Limit patient’s movement (surgical mask).

surgical mask

Transmission-based Precautions

Contact Precautions

◼ Used for clients known or suspected to have serious illnesses easily transmitted by direct contact. e.g. respiratory, skin, or wound infections, drug resistant bacteria (Vancomycine-resistant enterococci).

◼ Private room

◼ Wear gloves

◼ Wear gown

◼ Limit patient movement outside

◼ Using equipment to a single client (or same microorganism patients).

Isolation Practices

◼ Personal protective equipments

(medical asepsis) Gloves

Gowns

Face Masks

Eyewear

Isolation Practices

◼ Disposal of soiled equipment and supplies

Bagging

Linens

lab. Specimens

Dishes

BP equipments

Thermometers

Sharps

Isolation Practices

◼ Transporting Clients with Infections

◼ Psychosocial Needs of Isolation Clients

Sensory deprivation

Feelings of inferiority and low self-esteem.

Sterile Technique

Sterile technique (surgical asepsis)

- can be used in OR, LR, and special Dx. Procedures

- sterile field: a microorganism- free area

- ensure package intact and dry, and check for sterilization expiry.

- double packed objects

- using forceps, drape, sterile solutions.

- wearing sterile gloves by open and closed methods

- wearing sterile gown

sterile gloves

sterile package