2024 - Multiple Choice Questions

The addition of sodium bicarbonate to local anaesthetics
  1. Increases its protein binding
  2. Decreases its efficacy
  3. Inactivates the local anaesthetic
  4. Increases the speed of onset
Blood in the fetal aorta after the ductus arteriosus has SpO2 of
  1. 30%
  2. 60%
  3. 75%
  4. 90%
Propofol contains the following excipient to prevent bacterial growth:
  1. Disodium edetate (ETDA)
  2. Glycerol
  3. Egg phospholipid
  4. Sodium Hydroxide
Performing a midline lumbar puncture, the needle would pass through:
  1. the pia mater before obtaining CSF
  2. the epidural space before the ligamentum flavum
  3. the supraspinous ligament before the interspinous ligament
  4. The subarachnoid space before the dura mater
Besides glutamate, an agonist of the NMDA receptor is
  1. Glycine
  2. Magnesium
  3. Calcium
  4. Zinc
Which group of FFP should not be given to a person with an A+ blood group?
  1. A+
  2. B+
  3. A-
  4. AB+
What is the mechanism of action of ipratropium
  1. Beta agonist
  2. Muscarinic agonist
  3. Beta antagonist
  4. Muscarinic antagonist
With regards to the QT interval on the ECG
  1. is best monitored in aVF
  2. hyperkalaemia prolongs QT
  3. hypocalcaemia prolongs QT
  4. tachycardia prolongs QT
Complement is required for
  1. Anaphylaxis
  2. clearance of both endotoxins and bacteraemia
  3. normal c reactive protein release
  4. normal activation of the coagulation cascade
In smooth muscles
  1. spontaneous pacemaker potentials are generated
  2. contraction is triggered by the binding of calcium to troponin C
  3. de-phosphorylation of myosin light chains stimulates contraction
  4. there is a variable length-to-tension relationship
Which is the lowest pressure?
  1. 0.01 atm
  2. 5 kPa
  3. 10mmHg
  4. 15cmH2O
Normal alveolar air is best represented by which set of values?
  1. a temperature of 22oC, absolute humidity of 10 mg/L and relative humidity of 50%.
  2. a temperature of 37oC, absolute humidity of 22 mg/L and relative humidity of 50%.
  3. a temperature of 37oC, absolute humidity of 44 mg/L and relative humidity of 100%.
  4. a temperature of 33oC, absolute humidity of 37 mg/L and relative humidity of 100%.
Which step demonstrates the greatest drop in pO2 in the oxygen cascade in health?
  1. from trachea to alveolus
  2. from environment to larynx
  3. from alveolus to mitochondria
  4. from alveolus to capillary blood
In which tissue will the thiopentone concentration be greatest one hour after intravenous bolus administration?
  1. Liver
  2. Fat
  3. Muscle
  4. Plasma
The binding of adenosine to the P1 receptor leads to the activation of which class of ion channel?
  1. T-type Ca2+ channels
  2. Na+ channels
  3. L-Type Ca2+ channels
  4. K+ACh channels
Which structure is the most medial in the femoral triangle?
  1. The femoral vein
  2. The femoral nerve
  3. The deep inguinal lymphatics
  4. The femoral artery
Which of the following statements is true regarding the circulatory transition at birth?
  1. Indomethacin or ibuprofen can prolong the time to closure of the ductus arteriosus
  2. There is a persistent shunt across the foramen ovale after birth
  3. The ductus arteriosus functionally closes within 72 hours of birth
  4. Inflation of the lungs leads to an increase in right ventricular pressures
Which subunit of g-protein acts as a GTPase?
  1. the Gα subunit
  2. the Gβ subunit
  3. the Gγ subunit
  4. the Gδ subunit
What is the mechanism of action of morphine at μ-opioid (mu) receptors?
  1. The receptor acts as a ligand-gated ion channel and allows the efflux of potassium from the cells, resulting in membrane hyperpolarisation and decreased neuronal excitability
  2. The receptor acts as a G-protein-coupled-receptor, with the G-protein activating adenylyl cyclase, resulting in increased intracellular cAMP and increased neuron excitability
  3. The receptor acts as a G-protein-coupled-receptor, with the G-protein resulting in the production of IP3 and DAG, which subsequently activate potassium efflux channels, resulting in membrane hyperpolarisation and decreased neuronal excitability
  4. The receptor acts as a G-protein coupled receptor, with the G-protein interacting directly with a potassium efflux channel, resulting in membrane hyperpolarisation and decreased neuronal excitability
Which of the following is true when considering the control of temperature
  1. it involves afferent input from cutaneous cold receptors
  2. shivering begins at a set core temperature regardless of the ambient temperature
  3. the central control is in the hippocampus
  4. the spinal cord is a passive conductor of temperature signals