Anaesthetics

Question 1

What are 3 simple maneuvers that can relieve the majority of airway obstruction secondary to poor pharyngeal muscle tone?

Answer 1

Head tilt, chin lift, jaw thrust

Question 2

Describe a oropharyngeal airway

Answer 2

Easy to insert and use
No paralysis required
Ideal for very short procedures
Most often used as a bridge to a more definitive airway

Question 3

Describe a laryngeal mask

Answer 3

Widely used
Very easy to insert
Device sits in the pharynx and aligns to cover the airway
Poor control against reflux of gastric contents
Paralysis not usually required
Commonly used for a wide range of anaesthetic uses, especially in day surgery
Not suitable for high pressure ventilation

Question 4

Describe a tracheostomy

Answer 4

Reduces work of breathing and dead space
May be useful in slow weaning
Widely used in ITU
Dries secretions, humidified air as required

Question 5

Describe an endotracheal tube

Answer 5

Provides optimal control of the airway once the cuff is inflated
May be used for short term or long term ventilation
Errors in insertion may lead to oesophageal insertion (therefore end tidal CO2 usually measured)
Paralysis often required
Higher ventilation pressures can be used

Question 6

Criteria for brain death

Answer 6

Fixed pupils which don’t respond to sharp changes in the intensity of the incident of light
No corneal reflex
Absent oculo-vestibular reflexes (no eye movements following insertion of cold water into ear - caloric test)
No response to supraorbital pressure
No cough reflex to bronchial stimulation or gagging response to pharyngeal stimulation
No observed resp effort in response to disconnection of the ventilator long enough (typically 5 mins)

Question 7

What is a condition seen after administration of anaesthetic agents?

Answer 7

Malignant hyperthermia

Question 8

Presentation of malignant hyperthermia

Answer 8

Hyperpyrexia

Muscle rigidity

Question 9

Pathology of malignant hyperthermia

Answer 9

Excessive Ca2+ release from the sarcoplasmic reticulum of skeletal muscles
Associated with a gene defect on chromosome 19 encoding the ryanodine
Susceptibility is in an autosomal dominant fashion

Question 10

Causative agents of malignant hyperthermia

Answer 10

Halothane
Suxamethonium
Antipsychotics (neuroepileptic malignant syndrome)

Question 11

Investigations of malignant hyperthermia

Answer 11

Raised CK

Contracture tests with halothane and caffeine

Question 12

Management of malignant hyperthermia

Answer 12

Dantrolene

Question 13

How does dantrolene work?

Answer 13

Prevents Ca2+ release from the sarcoplasmic reticulum

Question 14

What is suxamethonium?

Answer 14

Depolarising muscle relaxant

Question 15

Example of action to take about blood transfusion if about to have a procedure where chance of transfusion is unlikely

Answer 15

Group and save

Question 16

Examples of operations which are unlikely to have a blood transfusion

Answer 16

Simple hysterectomy
Appendectomy
Thyroidectomy
Elective lower segment caesarean section 
Laparoscopic cholecystectomy

Question 17

Example of action to take about blood transfusion if an operation has a likely chance of infusion

Answer 17

Cross match 2 units

Question 18

Example of operations which are likely to have a chance of blood transfusion

Answer 18

Salpingectomy for ectopic pregnancy

Total hip replacement

Question 19

Example of action to take about blood transfusion if an operation has a definite need of blood transfusion

Answer 19

Cross match 4 - 6 units

Question 20

Examples of operations that have a definite need for blood transfusion

Answer 20

Total gastrectomy
Oophrectomy
Oesophagectomy
Elective AAA repair
Cystectomy
Hepatectomy

Question 21

Treatment of malignant hyperthermia

Answer 21

Dantrolene

Question 22

What is the muscle relaxant of choice for rapid sequence induction for intubation?

Answer 22

Suxamethonium

Question 23

Most likely cause of post op fever day 1 - 2

Answer 23

WIND

• pneumonia
• aspiration
• PE

Question 24

Most likely cause of post op fever day 3 - 5

Answer 24

UTI (esp if was catheterised)

Question 25

Most likely cause of post op fever day 5 - 7

Answer 25

WOUND

• infection at surgical site
• abscess formation

Question 26

Most likely cause of post op fever day 5 +

Answer 26

WALKING

• DVT
• PE

Question 27

Causes of post op fevers at any time

Answer 27

Drugs
Transfusion reactions
Sepsis
Line contamination

Question 28

Which anaesthetic agent has inherent anti-emetic properties?

Answer 28

Propofol