MCQ QUESTIONS

Dr Ed Hammond, Exeter

Question 1

Nerve stimulators

1. Double burst is of particular value in assessing blockade when there is no response to the train-of-four
2. A fading pattern to the train-of-four excludes prolonged action of suxamethonium 
3. When used to locate nerves for regional blockade the positive electrode should be attached to the locating needle
4. The post tetanic count is particularly useful for assessing the patient's suitability for extubation
5. The ideal nerve for neuromuscular blockade assessment is generally considered to be the facial nerve

Question 2

The following potentiate the action of non-depolarising neuromuscular blockers

1. Diethyl ether
2. Quinidine
3. Enflurane
4. Lithium
5. Dantrolene

Question 3

When looking at an ECG

1. A bifid P wave may indicate that the patient has mitral stenosis
2. Peaked P waves are associated with right atrial hypertrophy
3. A short PR interval indicates that the patient has Wolff-Parkinson-White syndrome
4. Left bundle branch block is associated with a secondary R wave in V6
5. U waves are associated with hypothermia

Question 4

The following ECG changes are associated with the correct cause

1. U waves - Hypothermia
2. T wave flattening - Hypothyroidism
3. Short QT Interval - Hypercalcaemia
4. Biphasic P wave in V1 - Mitral stenosis
5. T wave inversion - Hypokalaemia

Question 5

The following ECG changes occur with hypokalaemia

1. Tall T waves
2. ST elevation
3. Loss of P waves
4. T wave inversion
5. Prominent U waves

Question 6

The CVP trace

1. The c wave follows the X descent
2. The X descent occurs in (ventricular) diastole
3. The v wave results from right atrial filling against a closed tricuspid valve
4. Cannon waves are seen in complete heart block
5. The a wave is of variable size in atrial fibrillation

Question 7

Anaesthesia breathing circuits

1. The Lack circuit is a Mapleson D system
2. The Magill attachment is more efficient for spontaneous breathing than for controlled ventilation
3. The recommended fresh gas flow rate for controlled ventilation through a Bain circuit is 70 ml/kg body weight
4. Minimum fresh gas flow to avoid rebreathing using a Mapleson A is equal to that patient's minute ventilation
5. The Mapleson F system is a modification of the Mapleson E system

Question 8

The following cause a rise in the end-tidal carbon dioxide level (assuming constant ventilation)

1. Hypothermia
2. Malignant hyperpyrexia
3. Pulmonary embolus
4. Disconnection of the inner tube of a Bain circuit
5. Failure of the endotracheal tube cuff

Question 9

The concentration of vapour in the gas mixture emerging from the outlet port of a vaporiser depends on

1. Saturated vapour pressure of the agent
2. Flow characteristics of the vaporiser
3. Duration of use
4. Surface area of the agent in contact with the gas mixture
5. Temperature

Question 10

Anaesthesia at high altitude (using a plenum vaporiser)

1. The concentration delivered by the vaporiser will be higher than the dialled value
2. The concentration dialled into the vaporiser will need to be higher for the same effect
3. The concentration dialled into the vaporiser will need to be lower for the same effect
4. The inspired oxygen concentration may need to be increased
5. The anaesthetic potency of 50% nitrous oxide will be reduced

Question 11

A low resistance to gas flow is a feature of the following vaporizers

1. Oxford minature vaporizer
2. Epstein Macintosh Oxford vaporizer
3. Copper Kettle Vaporizer
4. Goldman Vaporizer
5. Boyle's bottle

Question 12

The following are true concerning humidity and humidification of gases

1. Relative humidity is the ratio of absolute humidity to saturated humidity at a specified temperature
2. Operating theatre humididty should be maintained at no more than 30%
3. Heat and moisture exchangers can achieve 40% humidity
4. A nebuliser works on the poiseuille effect to entrain water across a pressure drop
5. The water trap for a simple bottle humidifier must be larger than the humidifier bottle

Question 13

During brachial plexus blockade

1. The interscalene approach commonly leads to inadequate blockade of the ulnar nerve
2. The axillary approach may lead to Horner's syndrome
3. The supraclavicular approach commonly leads to inadequate blockade of the axillary nerve
4. Bilateral interscalene blocks should be used for bilateral shoulder manipulation surgery
5. The axillary approach commonly leads to inadequate blockade of the median nerve

Question 14

Complications of retrobulbar blockade for cataract surgery include

1. Bradycardia
2. Retinal detachment
3. Brain stem anaesthesia
4. Vitreous haemorrhage
5. Optic nerve damage

Question 15

Effects of epidural blockade include

1. A greater degree of hypotension when adrenaline (epinepherine) containing local anaesthetics are used
2. Sympathetic blockade before sensory blockade
3. Anterior spinal artery syndrome
4. Reduced tidal volume with a normal block to T4
5. Reduced peristalsis

Question 16

A successful stellate ganglion block may cause

1. Ipsilateral miosis
2. Contralateral nasal congestion
3. Bilateral ptosis
4. Ipsilateral exomphalos
5. Horners syndrome

Question 17

Concerning brachial plexus blockade

1. The interscalene approach provides for anaesthesia to the ulnar border of the forearm
2. The supraclavicular approach is not reliable to produce anaesthesia to the hand
3. The axillary approach is least likely to cause pneumothorax
4. Diaphragmatic paralysis is a complication
5. Puncture of an artery may be deliberate

Question 18

Inguinal hernia field block

1. Blocks the ilioinguinal, iliohypogastric and genitofemoral nerves
2. May be employed for testicular surgery
3. Prilocaine 0.5% may be used
4. Depends on depositing local anaesthetic between internal and external oblique
5. Quadriceps weakness is a complication

Question 19

Serum Na⁺ 120 mmol/l and K⁺ 6.4 mmol/l are consistent with

1. Hyperaldosteronism
2. Renal failure
3. Hypopituitarism
4. Adrenocortical insufficiency
5. Cushings disease

Question 20

The following conditions are associated with a haemoglobin concentration of 7 g/dl and a mean corpuscular volume of 70 fl

1. Iron deficiency anaemia
2. Acute blood loss
3. Folate deficiency
4. Renal failure
5. Thalassaemia

Question 21

Obesity is associated with

1. An increase in the incidence of airway complications
2. Increased functional residual capacity (FRC)
3. Increased DO₂ (Oxygen delivery)
4. Pulmonary hypertension
5. Quetelet index of 24.5

Question 22

Diathermy safety

1. Ohm's law states that voltage = current x resistance
2. Diathermy works because there is a high current density at the active electrode
3. The heat energy produced by cautery is proportional to the current at the tip of the active electrode
4. Bipolar diathermy requires a passive electrode ('diathermy plate')
5. Poor contact of the passive electrode ('diathermy plate') may lead to inadvertent patient burns

Question 23

With regard to electrical safety and prevention of explosions

1. Nitrous oxide is not flammable at atmospheric pressure
2. Anaesthetic machines should be isolated from 'earth' to prevent completion of an electrical circuit
3. Currents of 10 microamps may initiate ventricular fibrillation
4. The neutral connection of a circuit is not at earth potential at the patient end of the circuit
5. In surgical diathermy the heat released depends on the square of the potential difference between electrodes

Question 24

Ephedrine is unlikely to be effective in reversing hypotension in patients chronically receiving the following medication

1. Reserpine
2. Alpha-methyl dopa
3. Phenoxybenzamine
4. Clonidine
5. Propranolol

Question 25

Heat loss

1. Conduction is the largest factor in patient heat loss
2. Radiation accounts for about 10% of the total heat loss
3. Convection is due to heating of the adjacent air layer which is replaced by cooler air from the surroundings
4. Heat lost in breathing dry gases is approximately 15% of total heat loss in the anaesthetised subject
5. Burns from faulty heating equipment are more likely in the vasoconstricted patient