richard purchon rodp 2013 updated 2017 · gas laws gay-lussac’s law states that: the pressure of...

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Richard Purchon RODP 2013 updated 2017

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GAS LAWS

Gay-Lussac’s Law states that: The pressure of a fixed mass and fixed

volume of a gas is directly proportional to the gas's temperature. If a

gas's temperature increases then so does its pressure, if the mass and

volume of the gas are held constant.

or

Charles' law (also known as the law of volumes) is an experimental

gas law which describes how gasses tend to expand when heated. As

temperature increases volume increases.

Boyle's law describes the relationship between the pressure and volume

of a gas, if the temperature is kept constant. At a fixed temperature,

pressure and volume are inversely proportional (while one increases,

the other decreases).

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Avogadro's law At the same temperature and pressure the number of

molecules in a specific volume of gas is independent of the size or mass

of the gas molecules.

As an example, equal volumes of molecular hydrogen and nitrogen

would contain the same number of molecules, as long as they are at the

same temperature and pressure.

.

Dalton's law (also called Dalton's law of partial pressures) states that

the total pressure exerted by a gaseous mixture is equal to the sum of

the partial pressures of each individual component in a gas mixture.

or

T denotes temperature.

P denotes pressure.

V denotes the volume.

p constant pressure.

k constant pressure and volume.

n is the amount of substance of the gas

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MEDICAL GAS

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GAS:

Oxygen

SYMBOL:

O2

PIN INDEX:

2:5

FULL PRESSURE @ 15ºc

13700 KPa

GAS: Nitrous Oxide

SYMBOL:

N2O

PIN INDEX:

3:5


4400 KPa

GAS:

Cyclopropane

SYMBOL:

C3H6

PIN INDEX:

3:6


500 KPa

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GAS:

Nitrogen

SYMBOL:

N2

PIN INDEX:

1:4


2200 KPa

GAS:

Carbon Dioxide

SYMBOL:

CO2

PIN INDEX: 1:6


5000 KPa

GAS:

Oxygen & Carbon Dioxide

SYMBOL:

O2 + CO2

PIN INDEX:

2:6


13886 KPa

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GAS:

Oxygen & Helium

SYMBOL:

O2 + He

PIN INDEX:

2:4


13500 KPa

GAS:

Medical Air

SYMBOL:

21% O2 + 78% N + 1% Ar

PIN INDEX: 1:5


13500 KPa

GAS:

Entonox / Nitronox

SYMBOL:

O2 + N2O

PIN INDEX:

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13700 KPa

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� Minimum Alveolar Concentration = MAC

� Anesthetic potency is measured in MAC

� 1 MAC is the Minimum Alveolar Concentration at which

50% of humans have no response (movement) to surgical

stimulus (skin incision)

� MAC awake is the alveolar concentration when 50% of

persons will awake to vocal stimulus

� MAC is directly proportional to the partial pressure of the

anesthetic agent in the CNS

� MAC is consistent within a species and between species

� MAC is different for each inhaled agent

Halothane (Fluothane):

MAC 0.75% in Oxygen

Introduced in 1956

Induction 2 to 4 % in O2,

0.8% in 65% N2O

Maintenance 0.5 to 2%

Halothane is able to trigger malignant

hyperthermia. Hepatic necrosis occurs in one of

6,000 to 35,000 cases and is often fatal.

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Enflurane (Ethrane):

MAC 1.58% in Oxygen

Introduced in 1972

Induction 1 to 10 % in O2

1.5 to 3% in 65% N2O.


Emergence is a little slower than Isoflurane. It can

trigger malignant hyperthermia. Theoretical risk of

fluoride ion toxicity occurring with renal failure.

Isoflurane (Forane):

MAC 1.28% in Oxygen

Introduced in 1981

Induction 1 to 4% in O2

1.5 to 3% in 65% N2O


It can trigger malignant hyperthermia. There have

also been reports of hepato-toxicity associated with

the repeated use of Isoflurane.

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Sevoflurane (Ultane):

MAC 2.5% in Oxygen

Introduced in 1990


0.7 to 2% in 65% N2O


The low tissue solubility of Sevoflurane results in

rapid elimination and awakening. Sevoflurane

can trigger malignant hyperthermia in susceptible

patients.

Desflurane (Suprane):

MAC 6% in oxygen

Introduced in 1992


Maintenance 2 to 6%

The low tissue solubility of Desflurane results in

rapid elimination and awakening. It can trigger

malignant hyperthermia. Airway irritation and

reactivity with high concentrations unsuitable for

use in gaseous induction.

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Stage 1 – is the stage of analgesia and last from the beginning of administration of the gas

until consciousness is lost

The pupils will be normal size and reactive, muscle tone normal & breathing using

intercostal muscles and diaphragm

Stage 2 – is the stage of excitement, lasting from loss of consciousness until settled regular

breathing begins. During this period the patient may struggle, breath hold, vomit or

cough.

The pupils will be dilated & there is loss of the eyelash reflex

Stage 3 – once settled regular breathing has begun, the stage of surgical anaesthesia has

been reached and the operation my begin.

The pupils start by being slightly constricted and gradually dilate. This stage ends with

diaphragmatic paralysis

Stage 4 – if more anaesthetic is given, the patient enters the fourth stage (of over-dosage)

and their breathing and circulation will ultimately stop.

Constitutes an anaesthetic catastrophe, with apnoea, loss of all reflex activity and fixed,

dilated pupils

Kyed Vaporiser fillers

The key filler is designed to be used

exclusively with key fill vaporizers. This is an

agent specific adapter that prevents the

inadvertent mixing of agents.

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Breathing Systems

Mapleson A - the Magill and Lack circuits

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Mapleson B and C - Rebreathing of exhaled gases occurs even when

very high fresh gas flow rates are used, since inspiration is taken from

the same space into which the previous breath was expired. These are

unsatisfactory for anaesthesia, but may be used in emergency for

resuscitation.

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Mapleson D - the modified Bain circuit.

Mapleson E - Ayre's T piece and the Bain circuit.

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"Mapleson F" - not originally classified by Mapleson, but is used to

refer to Jackson-Rees' modification of Ayre's T-piece.

Waters Canister consists of a Mapleson C system with a soda lime

canister positioned between the APL valve and the reservoir. This

system is not widely used.

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AIRWAY MANAGEMENT

Endo Tracheal Tube and Flexible Endo

Tracheal Tube

inserted into the trachea during anaesthesia or

to provide ventilatory support. Most tubes have

an inflatable cuff to seal the trachea and

bronchial tree and have a murphys eye at the

distal end.

Adult sizes: 6, 6.5, 7, 7.5, 8, 8.5, 9

Paediatric sizes: 2.5 – 6

LGT-Laryngectomy tube

For operations on the larnyx and trachea

including:

Excision or repair of the larynx and Temporary

tracheostomy.

Adult sizes: 6, 6.5, 7, 7.5, 8, 8.5, 9

North-Facing Nasal Endotracheal Tube

Designed specifically for ENT and MaxFacs

surgery Ensures good access to the face

allowing the surgeon to observe the effect of

manipulation of the maxilla on facial symmetry

Adult sizes: 6, 6.5, 7, 7.5, 8.

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South-Facing Ring Adair Elwyn (RAE)

Endotracheal Tube

Directs tube downward to rest on patient's chin,

used for ENT and MaxFacs surgery such as

Tonsillectomy.

Available in all Adult and Peadiatric ETT sizes

both cuffed and uncuffed

Double-lumen Endobronchial tube

Used for thoracic surgery bronchial and

tracheal cuffs. Curved to the left or right to

allow single-lung ventilation

Laryngeal Mask Airway and Flexible

Laryngeal Mask Airway

consist of a tube with an inflatable cuff that is

inserted into the pharynx. and is seated over the

pyriform fossae. Designed for use without the

need for laryngoscopy or muscle relaxants.

Adult sizes: 3, 4, 5

Paediatric sizes: 1.5, 2, 2.5

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iGel Supragolittic Airway:

single use, non-inflatable supraglottic airway

device, anatomical seal of the pharyngeal,

laryngeal and perilaryngeal structures whilst

avoiding compression trauma.

Pro Seal

a double cuffed tube designed for use with

Positive Pressure Ventilation, the second

posterior cuff improves the seal to the

hypopharynx The second tube placed lateral

to the airway allows the escape of fluids from

the stomach and reduces the risks of gastric insufflation and pulmonary

aspiration.

Intubating Laryngeal Mask Airway:

Used for blind endotracheal intubation. It

allows for an endotracheal tube of up to be

passed through, and does not require head

and neck manipulations on insertion.

VBM Combi Laryngeal Tubes

Supraglottic airway alternative to tracheal

intubation or mask ventilation. Both cuffs are

inflated from a single source, designed for positive pressure ventilation

as well as for spontaneously breathing patients.

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Tulip

A cross between a Guedel airway and Laryngeal

Mask

The Tulip removes the need for the patient to have the airway tube

replaced. ‘one-size-fits-all-adults’, eliminating the need for multiple

sizes.

Nasopharyngeal Airway

used to maintain a conscious patients airway.

Contraindicated in patients with severe head or

facial injuries, due to the possibility of direct

intrusion upon brain tissue

Oropharyngeal Guedel Airway used to maintain an unconscious patients airway.

By preventing the tongue from covering the

epiglottis.

Adult sizes: 2, 3, 4

Paediatric sizes: 000, 00, 0, 1

Berman Intubating Pharyngeal Airway

Ideal for fiber optic bronchoscopy accommodates

the passage of an endotracheal tube through its

center. The airway can then be opened

longitudinally and separated from the tracheal

tube.

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A guide to size and length of paediatric ETT’s

Age Weight

(kg) Size Length

Neonate 2-4 2.5-3.5 10-12

1-6 mon 4-6 4-4.5 12-14 6-12 mon 6-10 4.5-5 14-16

1-3 yr 10-15 5-5.5 16-18

4-6 yr 15-20 5.5-6.5 18-20

7-10 yr 25-35 6.5-7 20-22

10-14 yr 40-50 7-7.5 22-24

W weight in Kgs

E electricity (weight x 4j/kg)

T tube size (age /4 +4)

F fluid

A adrenaline (10mcg/kg)

G glucose

LMA recommended sizes and cuff inflation volumes

Age Weight

(kg) Size Cuff Vol

Neonate 2-5 1 4ml

Infant 5-10 1.5 7ml

Infant 10-20 2 10ml

child 20-30 2.5 14ml

child 30-50 3 20ml

adult 50-70 4 30ml

adult 70-100 5 40ml

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Difficult airways:

LEMON airway assessment method

The score with a maximum of 10 points is calculated by assigning 1

point for each of the following LEMON criteria:

• L = Look externally (facial trauma, large incisors, beard or

moustache, large tongue)

• E = Evaluate the 3-3-2 rule (incisor distance-3 finger breadths,

hyoid-mental distance-3 finger breadths, thyroid-to-mouth

distance-2 finger breadths)

• M = Mallampati (Mallampati score > 3).

• O = Obstruction (presence of any condition like epiglottitis,

peritonsillar abscess, trauma).

• N = Neck mobility (limited neck mobility)

If an intubated patient’s condition deteriorates, consider the following

possibilities (DOPE):

• Displacement of the tube from the trachea

• Obstruction of the tube

• Pneumothorax

• Equipment failure

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Mallampati score

is used to predict the ease of intubation. It is determined by

looking at the anatomy of the oral cavity; specifically, the

visibility of the base of uvula, tonsil pillars and soft palate.

Class 1: Full visibility of tonsils, uvula and soft palate

Class 2: Visibility of hard and soft palate, upper portion of

tonsils and uvula

Class 3: Soft and hard palate and base of the uvula are

Visible

Class 4: Only Hard Palate visible

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Macintosh blade

A curved adult laryngoscope blade

used for intubation. designed to pass into the

vallecula and lift local

structures in order to facilitate

intubation.

Miller blade.

sits posterior to the epiglottis,

trapping it while exposing the glottis and vocal

folds. usually used for infants, this is due to the

larger comparative size of the epiglottis.

McCoy blade

Can be used to lift up the epiglottis

and improve the view of the larynx. Useful as

an alternative to other blades (Macintosh)

during difficult intubation situations.

Polio blade

Laryngoscope with wide-angled

blade popular in obstetric

anaesthesia. patients with large

chest/breasts and short necks as in

late pregnancy. Originally designed for polio

patients.

Robert Shaw blade

The blade is for infants and children it is gently

curved over the distal third and is tapered to fit

the shape of the paediatric airway and lifts the

epiglottis indirectly.

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Glidescope, C Mac & McGrath

A video laryngoscope used for tracheal intubation, facilitated by the use

of the Verathon rigid stylet that is curved to follow the 60° angulation

of the blade.

AirTraq

The Airtraq is an anatomically shaped

laryngoscope It provides a magnified angular

view of the larynx and adjacent structures,

during 100% of intubation. No hypertension of the neck required

allowing intubation in any position,

Bonfils Scope

a fiberoptic rod coupled with a focusing lens, it

has a fixed shape with a long narrow axis and

upward bent distal tip. The focusing lenses is

attached to a camera and video imaging

screens. The Bonfils enables indirect

visualisation of the cords and railroading of Endo tracheal tubes in order

to secure the airway.

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SELLICK’S MANOUVER

Cricoid pressure was described by Sellick in 1961 as a means to

control regurgitation until Intubation with a cuffed endotracheal tube

was completed.

This helps to prevent pulmonary aspiration from passive regurgitation

of gastrict contents, because large volumes of acidic stomach contents

induce severe aspiration pheumanitis and greatly increase morbidity .

Effective application of cricoid pressure involves occluding the

oesophagus with posterior displacement of the cartilaginous

cricothyroid ring by pressing back against the bodies of the cervical

vertebrae using the thumb index and first fingers to locate and apply

pressure.

In numerous studies it has been determined that a pressure of at least

30-40 newtons is needed to effectively occlude the oesophagus.

Cricoid pressure can provide such an effective barrier to the flow of

gastrict contents that the oesophagus can rupture during active

vomiting. There have been recorded cases of cricoid cartilage fracture,

aggravation of cervical spine injury and complete airway obstruction

due to undiagnosed lingual thyroid mass.

Sellick’s Manouver is not the same as BURP!

Backward Upward Rightward Pressure

This technique demonstrates significant improvement in visualizing the

vocal cords during laryngoscopy

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The plunger of a 20-ml syringe (B-D Plastipak) is withdrawn to the 20

ml mark so that the syringe contains 20 ml of air. The end is then

occluded with an obturator (Vygon dualend stopper; a push-and-twist

technique is recommended for reasons that will become obvious when

tried in practice). Depressing the plunger to the 10 ml mark requires a

force of 30 N to be exerted by the operator’s fingers

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ASA

• American Society of Anesthesiologists (ASA) grade is the most commonly used grading

system • ASA accurately predicts morbidity and mortality • 50% of patients presenting for elective surgery are ASA grade 1

ASA Grade

DEFINITION MORTALITY %

I Healthy individual with no systemic disease 0.05

II Mild systemic disease not limiting activity 0.4

III Severe systemic disease that limits activity but is not incapacitating 4.5

IV Incapacitating systemic disease which is constantly life-threatening 25

V

VI

Moribund, not expected to survive 24 hours with or without surgery A declared brain-dead patient whose organs are being removed for donor purposes

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101

The Venture mask delivers a known oxygen

concentration to patients on controlled oxygen

therapy. Venturi masks are considered high-

flow oxygen therapy devices. This is because

venture masks are able to provide total

inspiratory flow at a specified FIO2 to patients

therapy. The colours and respective delivery concentrations are;

Blue 24%, White 28%, Yellow 35%, Red 40%, Green 60%.

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FLUIDS CRYSTALLOIDS

Crystalloids are aqueous solutions of mineral salts or other water-

soluble molecules. Which pass from the circulation volume into the

interstitial fluid.

Hartmans Solution (Compound Sodium Lactate)

Sodium Chloride

Glucose

Dextrose

Sodium Bicarbonate

Manitol

COLLOIDS

Colloids contain larger insoluble molecules, such as gelatin. Colloid

molecules are to large to cross the cell membrane and therefore stay in

the circulating volume.

Dextrans

Gelofusin

Geloflex

Volpex

Blood

Platelets

Plasma

Blue = for BOYS 22G

Pink = Pathetic 20G

Green = Good 18G

Grey = Great 16G

Orange = Orgasmic 14G

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Blood Grouping There are 30 major blood group systems The most important are the

ABO and the RhD blood group system and its related Antigens and

Antibodies.

Blood Products are typically only given

when a patients

haemoglobin falls below

8g/dL on Arterial

Blood Gas

RBC’s a unit of red blood

cells typically contains

450mls and is given strictly

as ABO and RhD

compatible.

FFP fresh frozen

plasma, is the liquid portion

of blood that has been

centrifuged and separated

it is issued in units determined by patient weight and contains the major plasma proteins and coagulation

factors V and VIII..

Platelets, are involved in the formation of blood clots. They release growth factors that aid in the repair and

regeneration of connective tissues. Pooled whole-blood platelets are stored under constant agitation at 20–

24 °C and have a short shelf life of typically up to five days.

Cryoprecipitate, is a frozen blood product prepared from plasma. Each 15 mL unit typically contains 100

IU and 250 mg of the clotting agents factor VIII and fibrinogen.

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Central Venous Catheter

Central venous catheters are commonly placed in the internal jugular

vein, external jugular vein, subclavian vein or femoral vein. It is used to

administer medication or fluids, obtain blood tests, and directly obtain

cardiovascular measurements such as the central venous pressure.

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Arterial Cannulation

An arterial line is most commonly used to monitor the blood pressure

and to obtain samples for arterial blood gas measurements. It is usually

inserted in the radial artery; but can also be inserted into the brachial,

femoral, dorsalis pedis or ulnar arteries.

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Normal Blood Gas Results

PaO2 10.0 - 13.3

pH 7.35 - 7.45

PaCO2 4.7 - 6.0

Hb 12 - 18

Na+ 135 - 148

K+ 3.5 - 5.3

Ca+ 2.1 - 2.8

Cl+ 98 - 106

Glucose 3.7 - 5.2

Lactate 0.5 - 2

HCO3 22 - 26

BE -/+2

Metabolic acidosis Occurs when the body produces too much acid or when the kidneys are not removing enough acid from the

body.

↓ pH below 7.35

↓ HCO3 below 22

PaCO2 Normal

Metabolic alkalosis Occurs when the pH of tissue becomes elevated leading to increased bicarbonate levels.

↑ pH above 7.45

↑ HCO3 above 26

PaCO2 Normal

Respiratory acidosis

Occurs when an abrupt failure of ventilation occurs. Due to depression of the central respiratory centre by

cerebral disease or drugs or neuromuscular disease such as Myasthenia Gravis, or Guillain-Barré syndrome

↓ pH below 7.35

↑ PaCO2 above 45

HCO3 Normal

Respiratory alkalosis Occurs when some stimulus causes hyperventilation expelling CO2 from the circulation.

↑ pH above 7.45

↓ PaCO2 below 35

HCO3 Normal

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Anaesthesia for Ophthalmic and

ENT Procedures

10ml Sub Tenon and Peri Bulbar eye blocks

Hyalase 1,500μ Powder

Chirocaine 7.5mg/ml 10ml amp

Lignocaine 4% in 2ml amp

a) 5ml of Chirocaine mix with 1 amp Hyalase.

b)1ml of Chriocain Hyalase mix

5ml of Chirocaine

4mls of 4% lignocaine.

10ml Moffats Solution

Cocain solution (CD stock)

Adrenaline 1ml Amp

Sodium Bicarbonate 8.4% in 10ml amp

Sodium Chloride 0.9% in 10ml amp

2mls 5% Cocain solution

1ml 1:1000 Adrenalin

1.5mls 8.4% Sodium Bicarbonate

5.5mls Sodium Chloride

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Spinal & Epidural

Spinal anaesthesia is a form of regional analgesia involving injection of

a local anaesthetic into the subarachnoid space, through a fine needle,

The tip of the spinal needle has a point or small bevel. (Whitacre,

Sprotte, & Yale).

Epidural anaesthesia is a form of regional analgesia involving injection

of drugs through a catheter placed into the epidural space. The epidural

space is the space inside the bony spinal canal but outside the

membrane called the dura mater.

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Misuse of Drugs Regulations 2001

The 2001 Regulations divide CDs into five Schedules, which dictate the degree to

which a CD’s use is regulated. The Schedule in which a CD is placed depends upon its

medicinal or therapeutic benefit balanced against its harm when misused. Schedule 1

CDs are subject to the highest level of control, whereas Schedule 5 CDs are subject to

a much lower level of control.

Schedule 1

no therapeutic value for example Heroin, Crack Cocain, LSD.

Schedule 2

Of therapeutic value legally possessed and supplied by pharmacists and doctors. for

example methadone, diamorphine, morpine.

Schedule 3 drugs include Subutex and most of the barbiturate family.

The difference between Schedule 2 and Schedule 3 is limited to record keeping and

storage requirements in respect of schedule 2 drugs.

Schedule 4(i)

controls most of the benzodiazepines. can only be lawfully possessed under

prescription..

Schedule 4(ii) drugs can be possessed in medicinal form without a prescription as long as they are

clearly for personal use. For example steroids.

Schedule 5

drugs are sold over the counter and can be legally possessed without a prescription.

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The Misuse of Drugs and Misuse of

Drugs (Safe Custody)

(Amendment) Regulations 2007 In respect of Operating Department Practitioners and Controlled Drugs:

after paragraph (2) In regulation 8 (production and supply of drugs in Schedules 2 and

5)

&

after paragraph (3) In regulation 9 (production and supply of drugs in Schedules 3 and

4)

insert—

“(iii) an operating department practitioner to supply any drug otherwise than

for

administration to a patient in a ward, theatre or other department in

accordance

with the directions of a doctor, dentist, supplementary prescriber acting under

and

in accordance with the terms of a clinical management plan or, subject to

paragraph (2A), a nurse independent prescriber.”;

In respect of Midazolam:

(13) In paragraph 1 of Part 1 of Schedule 4 (controlled drugs subject to the

requirements of

regulations 22, 23, 26 and 27), omit “Midazolam”.

(14) In paragraph 1(a) of Schedule 3 (controlled drugs subject to the requirements of

regulations

14 to16, 18, 22 to 24, 26 and 27), after “Methyprylone” insert “Midazolam”.

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Propofol

Diprivan

Description: a milky oil in water emulsion

10mg/1ml (amp 200mg / 20ml)

Onset: 30 seconds

Duration: 10 minutes

Action: Hypnotic 15-25% ↓BP, ↓Pulse, 20%↓cardiac output.

Side Effects: 28% pain on injection, green urine and hair. Egg allergies.

Dose:

Induction 1.5-2.5mg/kg

Infusion 4-12mg/kg/hr

Sodium Thiopentone

Thiopental

Description: a Barbiturate yellow powder

500mg vial reconstituted with 20mls H2O

Onset: 30-45 seconds

Duration: 5 - 15 minutes

Action: Hypnotic anticonvulsant, ↓cardiac output 20%, ↓BP, ↓Reps,

↓ICP, ↓IOP ↓urine output

Side Effects: anaphylactoid reactions, extravasation causs tissue

necrosis.

Dose:

Induction 3-5mg/kg

ECT 0.5-2mg/kg prn

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Ketamin

Ketalar

Description: a clear colourless solution

Onset: within 30 seconds

Duration: 5-10 minutes

Action: Dissociative anaesthesia. ↑Pulse ↑BP ↑CVP, ↑cardiac output,

↑IOP

Side Effects: transient rashes in 15%, Emergence delirium and pain on

injection

Dose:

Induction 1.5-2mg/kg over 60seconds

Infusion 50μg/kg/min

Etomidate

Hypnomidate


2mg/ml (amp 20mg / 10ml)

Onset: within10-65 seconds


Action: Hypnotic, cardiovascular stable. ↓BP, ↓Reps, ↓tidal volume,

↓ICP, ↓IOP.

Side Effects: pain on injection, sedation of critically ill ↑mortaility.

Dose:

Induction 0.3mg/kg (∆ 70kg = 21mg)

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Midazolam

Hypnovel

Description: a clear colourless fluid


Onset:

Duration:

Action: a Hypnotic benzodiazepine CNS depresent, ↓BP, ↑ Pulse,

↓tidal volume, ↑Reps

Side Effects: occasional discomfort on injection.

Dose:

0.07-0.1mg/kg (∆ 70kg = max 7mg)

Flumazenil

Anexate

Description: a clear clourless solution

100μg/ml (amp 500μg / 5ml)

Onset: 30-60 seconds


Action: Benzodiazepine antagonist reversal generally used to

counteract the effects of Midazolam, reduces post-operative shivering.

Side Effects:↑BP dizziness, nausea and vomiting

Dose:

IV 100μg => maximum 1mg

Infusion 100-400μg/hour

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Suxamethonium

Anectine

Scolene

Description: a clear aqueous solution

50mg/ml (amp 100mg/ 2ml)

Onset: 30 seconds


Action: a depolarising fast acting muscle relaxant. ↑Ka, ↓Pulse and

cardiac arrest Fasciculations

Side Effects:

Malignant Hyperpyrexia, Guillain-Barr Syndrome

Dose:

Intubation 1-1.5mg/kg

Infusion 0.5-10mg/min

Vecuronium Bromide

Norcuron

Description: a white powder

10mg vial reconstituted with 5ml H2O (2mg/ml)

Onset: 2 minutes


Action: a non-depolarising muscle relaxant

Side Effects: anaphylactoid reactions, cross sensitivity with

Rocuronium.

Dose:

Intubation 0.8-0.1mg/kg

Maintenance 20-30μg/kg

Infusion 50-80μg/kg/hour

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Atracturonium

Tracrium



Onset: 90 seconds


Action: a non-depolarising muscle relaxant, Broncospasm may occur.

Side Effects: 80% undergoes Hofmann Elimination, ↓BP ↓Pulse, cross

sensitivity with Veruronium and Rocuronium.

Dose:

Intubation 0.3-0.6mg/kg

Maintenance 0.1-0.2mg/kg

Infusion 0.3-0.6mg/kg/hr

Rocuronium

Esmeron



Onset: 1 minute


Action: a non-depolarising muscle relaxant, neuromuscular blockade

leads to apnoea.

Side Effects: cross sensitivity with Veruronium and Atracturonium

Dose:

Intubation 0.6-1mg/kg

Maintenance 0.1-0.15mg/kg

Infusion 0.3-0.6mg/kg/hr

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Hofmann Elimination

Hofmann Elimination / Degradation is dependant on blood pH and

temperature. It metabolizes 80% of Atracurium to Laudanosine the

remaining 20% is metabolized hepatically or excreted renally.

Laudanosine originally isolated from Opium in 1871, it is a toxic

metabolite of the neuromuscular-blocking drμgs Atracurium and

Cisatracurium. It is a CNS stimulant that interacts with Opioid

receptors. High plasma concentrations produce hypotension and titanic

convulsions. In pregnancy, Laudanosine crosses the placental barrier.

Except for prolonged administration of Atracurium (In excess of 6

days), in intensive care units, Laudanosine accumulation and related

toxicity seem unlikely to be achieved in clinical practice. When

Cisatracurium is used, plasma concentrations of Laudanosine are lower.

Myasthemia Gravis Myasthemia Gravis, from Greek and Latin meaning “serious muscle

weakness” it is an autoimmune neuromuscular disease, in which

weakness is caused by circulating antibodies that block acetylcholine.

Onset can be sudden, symptoms are often intermittent. The first

noticeable symptom is weakness of the eye muscles, difficulty in

swallowing and slurred speech. In crisis a paralysis of the respiratory

muscles occurs, necessitating assisted ventilation. The heart is never

affected. Treatment consists manly of cholinesterase inhibitors such as

Neostigmine, to improve muscle function and immunosuppressant

drμgs to reduce the autoimmune process.

44


Neostigmine


2.5mg/ml (amp 2.5mg / 1ml)

Onset: 7-11 minutes


Action: a reversal of non-depolarising muscle relaxants, and for the

treatment of Myasthenia Gravis.

Side Effects: Nausea, Vomiting, Sweating and Lachrymation

Dose:

50-70μg/kg (max 5mg)

With Atropine 10-20μg/kg

Glycopyrronium 10-15μg/kg

PO 15-50mg 2-4 hourly(given down ET Tube)

Sugammadex Sodium

Bridion

Description: a clear colourless solution 100mg/ml (vial 200mg/2mls or

500mg/5mls)

Onset: upto 3 minutes

Duration: halflife 2.2 hours, clearance 2-24 hours typicaly 8 hours

Action: binds with Rocuronium and Vecuronium in plasma thereby

reducing the available amount of blocking agent.

Side Effects: vomiting, pain, nausea, hypotension, headache,

abdominal pain, gas, dry mouth, fever, chills, dizziness, mouth or throat

pain, cough, pain in extremities, muscle pain, insomnia, and anxiety

Dose:

2-4mg/kg

immediate reversal 16mg/kg bolus, followed by 1.2mg/kg after 3

minutes

45


Malignant Hyperthermia Malignant Hyperthermia is a rare life threatening condition triggered by

exposure to certain general anaesthesia drμgs, all of the vaporised

volatile agents and the depolarising muscle relaxant Suxamethonium.

Symptoms are charcteristicaly muscular rigidity, followed by a

hypermetabolic state, hypercapnia, tachycardia and hyperthermia at an

increase of 2ºc per hour. Treatment is IV Dantrolene and

discontinuation of all triggering agents. Dantrolene is the only drμg

know to be effective in the treatment of Malignant Hyperthermia.

Dantrolene sodium

Description: an Orange powder

20mg vial reconstituted with 60ml H2O

Onset: 15 minutes

Duration: 4-6 hours

Action: a muscle relaxant that is the only effective treatment for

malignant hyperthermia

Side Effects: irritant if extravasated, hepatic dysfunction in 2%

Dose:

Acute hyperthermia, 1-10mg/kg IV

46


Ephedrine Sulphate


30mg / ml (amp 1ml)

Onset: “RAPID”

Duration: 1 hour

Action: ↑cardiac output, ↑Resp, Broncodilation, ↓GFR

Side Effects: Insomnia, anxiety, tremor, nausea, vomiting and chest

pain complicate use of the drug.

Dose:

3 – 30mg IV

Metaraminol

Aramine


10mg/ml (amp 1ml)

Onset: 1-2 minutes

Duration: 20 – 60 minutes

Action: ↑BP, ↓Pulse, ↓Resp, ↑tidal volume,

Side Effects: Headaches, dizziness, tremor nausea and vomiting, rapid

↑BP=>LVF and cardiac arrest.

Dose:

0.5-5 mg IV

2 -10 mg IM/SC

47


Atropine


600μg /ml (amp 1ml)

Onset:

Duration: elimination half-life is 2.5hours

Action: ↑Pulse, ↑Resp

Side Effects: painfull when injected intramuscularly

Dose:

bradyasystolic arrest 0.5 - 1 mg IV up to 0.04 mg/kg.

symptomatic bradycardia 0.5 to 1 mg IV up to 3.0 mg

Glycopyrrolate

Robinul


200μg /ml (amp 600μg / 3ml)

Onset: 3 minutes

Duration: 2-3 hours

Action: ↑Pulse, Brochodilation

Side Effects: dry mouth, difficulty in micturation, & inhibition of

sweating.

Dose: Adult 0.2-0.4mg

Pead 4-10μg/kg

48


Morpine Sulphate


10mg / ml (amp 1ml)

Onset: IM 30-60 minutes

Duration: 3-4 hours

Action: Anaglesia, Respiratory depression, & Euphoria

Side Effects: ↓Pulse, ↓Resp, Bronchoconstriction, nausea, vomiting,

hallucinations, dependence.

Dose:

0.05-0.1mg/kg (∆ 70kg =>max 7mg)

Diamorphine hydrochloride

Description: a white powder

10mg vial reconstituted with10mls NaCl

1.5-2 times stronger than Morphine

Onset: “Rapid”





Dose:

5-10mg IV

2.5-5mg Epidural

49


Fentanyl

Sublimaze


50μg / ml (amp 100μg / 2ml)

50-80 times stronger than Morphine

Onset: 2-5 minutes





Dose:

1-100μg/kg (∆ 70kg =>7mg)

Alfentanil

Rapifen


500μg / ml (amp 1ml)

1/10 the strength of Fentanyl

Onset: 90 seconds



Side Effects: nausea, vomiting,

Dose:

10-50μg/kg IV (∆ 70kg => 3.5mg)

0.5-1μg/kg/min Infused

50


Remifentanil

Ultiva

Description: A white powder which becomes a clear colourless

solution when reconstituted with saline 1mg/2mg/5mg vials

Onset: 1-3 minutes

Duration: duration of infusion, half life 5-14 minutes

Action: Analgesia and respiratory depression

Side Effects: respiratory depression, bradcardia, nausea and vomiting

Dose:

boluses 1μg/kg

infusion 0.0125-1μg/kg/min

Naloxone hydrochloride

Description: A clear colourless solution

400mg / ml

Onset: 60 seconds


Action: a reversal of Opioid’s (Heroin or Morphine) counteracts

depression of the CNS and respiratory system

Side Effects: Ventricular dysrthmia

Dose:

Reversal of Analgesia 0.1-0.2mg

Opioid Overdose 0.4-2.0mg IV / IM / SC

51


Ondansatron

Zofran



Onset: one arm brain circulation (20-40 sec)

Duration: half life 3 hours

Action: Antiemetic

Side Effects: Constipation, Headache and flushing.

Dose:

4mg IV

Dexamethosone


4mg/ml (amp 1 ml)

Onset: one arm brain circulation (20-40 sec)

Duration: long

Action: corticosteroid with antiemetic properties

Side Effects: ↑micturation, ↓ICP, ↑GFR

Dose: 8mg IV

52


Electro Cardio Grams

53


54


PR Interval

Is the length along the baseline from the beginning of the P wave to the

beginning of th QRS complex. This Is normally 0.12 to 2.0 seconds in

duration. (3-5 small squares)

QT Interval

Is the beginning of the QRS complex to the end of the T wave. In the

presence of a U wave the measure should be from the beginning of the

QRS complex to the end of the U wave.

ST Segment

Is the length between the end of the S wave of the QRS complex and

the beginning of the T wave. It is electrically neutral.

PR Segment

It represents the delay in conduction from atrial depolarization to the

beginning of ventricular depolarization. It is also electrically neutral.

Sinus rhythm

the normal beating of the heart, as measured by an electrocardiogram

(ECG)

55


VF Coarse and Fine

Ventricular fibrillation uncoordinated contraction of the ventricles in

the heart. is characterised by chaotic electrical impulses, which

originate in the ventricles. These chaotic impulses fail to create Systole.

VF begins as a coarse, irregular deflection on the ECG,

then degenerates to a fine, irregular pattern,

and eventually becomes asystole.

Asystole

asystole is a state of no cardiac electrical activity and no cardiac output

or blood flow.

VT

Ventricular tachycardia is a fast heart rhythm. It is a potentially life-

threatening, because it may lead to ventricular fibrillation, asystole, and

sudden death.

56


AF

Atrial fibrillation uncoordinated contraction of the atria in the heart. Or

absence of P waves.

Atrial Flutter (AFL) is usually associated with tachycardia andoccurs most often in

individuals with cardiovascular disease, It is typically not a stable

rhythm, and frequently degenerates into atrial fibrillation (AF).

Ectopics, Bigeminy, and Trigeminy

are caused by the premature discharge of a ventricular ectopic focus

which produces an early and broad QRS complex.

Single ectopic beat.

57


Bigeminy every second beat.

Trigeminy every third beat.

Types of infra-Hisian bloc LBBB

Left bundle branch block (LBBB) is a cardiac conduction abnormality

activation of the left ventricle is delayed, which results in the left

ventricle contracting later than the right ventricle.

RBBB

In Right bundle branch block (RBBB) the right ventricle is not activated

by impulses in the right bundle branch but by impulses from the left

bundle branch traveling through the myocardium. which results in the

right ventricle contracting later than the left ventricle.

Types of AV nodal blocks

58


First Degree Heart Block In first-degree AV block, the impulse conducting from atria to

ventricles through the AV node is delayed and travels slower than

normal the PR interval is lengthened beyond 0.20 seconds and is greater

than 5 small squares.

Second Degree Heart Blocks Types 1 & 2 There are two distinct types of second-degree AV block, called Type 1

and Type 2. In both types, a P wave is blocked from initiating a QRS

complex. one or more (but not all) of the atrial impulses fail to conduct

to the ventricles

Type 1 (Mobitz I/Wenckebach)

is characterized by progressive prolongation of the PR interval

Type 2 (Mobitz II/Hay)

is characterized by intermittently nonconducted P waves.

59


Complete Heart Block

Third-degree AV block, also known as complete heart block, is the

impulse generated in the SA node does not propagate to the ventricles.

An accessory pacemaker in the lower chambers will typically activate

the ventricles. This is known as an escape rhythm.

Wolf Parkinson White

Wolff–Parkinson–White syndrome (WPW) is a syndrome of pre-

excitation of ventricles of the heart due to an accessory pathway known

as the bundle of Kent.

60


PEA EMD

Pulseless Electrical Activity or Electromechanical Dissociation refers to

any heart rhythm observed on the electrocardiogram that should be

producing a pulse, but is not. Possible causes are remembered as the 6

Hs and the 6 Ts

• Hypovolemia

• Hypoxia

• Hydrogen ions (Acidosis)

• Hyperkalemia or Hypokalemia

• Hypoglycemia

• Hypothermia

• Tablets or Toxins (Drug overdose)

• Cardiac Tamponade

• Tension pneumothorax

• Thrombosis (Myocardial infarction)

• Thrombosis (Pulmonary embolism)

• Trauma (Hypovolemia from blood loss)

61


NOTES

62


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Ltd

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