Anaesthetics

Question 1

Give the formula for calculating MAP

Answer 1

MAP = 2(DBP) + SBP /3

Question 2

According to ASA classification, what are the different levels of sedations?

Answer 2

1. Minimal Sedation (Anxiolysis) - drug - induced state during which the patient responds normally to verbal commands.
2. Moderate sedation (Conscious sedation) - a state where a purposeful response to verbal commands either alone or accompanied by light tactile stimulation is maintained.
3. Deep sedation - a state where the patient cannot easily be aroused but responds purposefully to repeated or painful stimulation.
4. GA - Drug induced loss of consciousness in which patients are not rousable even by painful stimulation.

Question 3

What are the most common causes of post intubation hypoxia?

Answer 3

The pneumonic DOPE can help you remember the most common causes of post-intubation hypoxia or deterioration

D - Displacement: check the endotracheal tube for displacement (right mainstem) or dislodgement

O - Obstruction: check the ETT for obstruction (mucous plug, kink in ventilator tubing)

P - Pneumothorax - get an xray

E - Equipment failure(unusual): disconnect patient from the ventilator and bag manually

Question 4

Name potential side effects of suxamethonium?

Answer 4

1. Suxamethonium apnoea
2. Hyperkalaemia
3. Malignant hyperthermia
4. Rhabdomyolysis

Question 5

What are the side effects of etomidate?

Answer 5

1. Pain on injection
2. thrombophlebitis
3. Nausea and vomiting
4. Adrenocortical suppression

Question 6

What are the contraindications to use suxamethonium for RSI?

Answer 6

1. Major Burns (After 24 hours)
2. Hyperkalaemia
3. Severe muscle trauma
4. Spinal cord injury causing paraplegia (day 10 - 100)
5. History of malignant hyperthermia.

Question 7

Contraindication to procedural sedation

Answer 7

1. Appropriately trained personnel are not available to perform the sedation.
2. Patients have an (ASA) classification of unstable class II or class IV and above (unless requiring immediate intervention, e.g. ventricular tachycardia)
3. Appropriate monitoring and resuscitation equipment are not available.
4. A general anaesthetic would be more appropriate.
5. The patient has an allergy or hypersensitivity to the relevant medications.
6. There is a high risk of aspiration e.g. acute alcohol intoxication.

Question 8

How much oxygen is required for transfer on spontaneously breathing patient. Give the formula.

Answer 8

2(Flow{L/min} x Length of transfer {mins})

Question 9

What is the immediate management for local anaesthetic toxicity?

Answer 9

1. Stop injecting the LA
2. Call for help
3. Maintain the airway and, if necessary, secure it with a tracheal tube
4. Give 100% oxygen and ensure adequate lung ventilation (hyperventilation may help by increasing plasma pH in the presence of metabolic acidosis)
5. Confirm or establish intravenous access
6. Control seizures: give a benzodiazepine, thiopental or propofol in small incremental doses
7. Consider drawing blood for analysis, but do not delay definitive treatment to do this

Question 10

What is the discharge criteria post sedation?

Answer 10

1. The patient return to their baseline consciousness
2. Vital signs are within normal limits
3. Respiratory status is not compromised
4. Nausea, vomiting, pain and discomfort has been adequately addressed.

Question 11

What factors predict difficult bag valve mask ventilation?

Answer 11

Mneumonic “MOANS”

M - Mask seal (Beard/trauma)
O - Obesity (BMI>26)
A - Age >55 
N - No teeth 
S - Stiff ventilation (ARDS/Asthma/Pregnancy)

Question 12

What factors predict difficult cricothyroidotomy?

Answer 12

Mneumonic “SHORT”

S - Previous surgery to the neck 
H - Haematoma of the neck 
O - Obesity (BMI>26)
R - Radiation to the neck 
T - Tumor of the neck