2022 - Multiple Choice Questions
What is the half-life of IV Salbutamol?
- 1-2 minutes
- 5-10 minutes
- 1-2 hours
- 2-5 hours
Mechanism: Liver metabolism -> Salbutamol 4-0 sulfate
Elimination half life: ~3 hours
A hollow bubble has surface tension acting on the internal and external surfaces of the bubble. Which formula is correct for the total surface tension acting on a bubble, where:
T = total surface tension acting on the bubble
P = pressure difference between the inside and outside of the bubble
r = radius of the bubble
- T = Pr/2
- T = Pr/4
- T = P/2r
- T = P/r2
LaPlace Eqn
ΔP = 2T/r
This applies where there is only 1 liquid-gas interface (e.g. in alveoli)
- For a bubble there are 2 liquid-gas interfaces (one inside the bubble, and one outside the bubble) -> i.e. there are 2 surfaces with surface tension
- This means that the pressure in the bubble would need to be twice as high as in a cavity with only 1 interface to produce the same radius (with the same surface tension)
What is the mechanism of action of Amiodarone?
- Blocks sodium and potassium channels
- Blocks adrenoreceptors and calcium channels
- Blocks sodium, potassium, and calcium channels
- Blocks sodium, potassium and calcium channels, and adrenoreceptors
According to the Poiseulle equation, flow is INVERSELY proportional to:
- Density
- Radius to the fourth power
- Pressure gradient
- Viscosity
What is the critical pressure of oxygen?
- 5 atm
- 15 atm
- 50 atm
- 500 atm
What is the main site of tissue damage in hyperoxic acute lung injury?
- Alveolar epithelium
- Septal connective tissue
- Pulmonary capillary endothelium
- Bronchial epithelium
On gram stain Serratia marcescens appears as:
- Gram negative cocci
- Gram negative bacilli
- Gram positive cocci
- Gram positive bacilli
What is the respiratory quotient of fat?
- 1.0
- 0.8
- 0.7
- 0.4
Which of these drugs has the highest volume of distribution?
- Fentanyl
- Alfentanil
- Remifentanil
- Morphine
Which of the following bacteria are aerobic?
- Actinomyces
- Bacillus
- Bacteroides
- Fusobacterium
What is the normal basal metabolic rate?
- 25 kcal/kg/day
- 40 kcal/kg/day
- 70 kcal/kg/day
- 100 kcal/kg/day
A patient with chronic respiratory alkalosis has a pH of 7.53 and a PaCO2 of 20mmHg, what should their expected HCO3- be?
- 10 mmol/L
- 14 mmol/L
- 21 mmol/L
- 28 mmol/L
When using the Cockcroft-Gault formula for estimating creatinine clearance, what correction factor is used to account for females?
- 0.70
- 0.75
- 0.80
- 0.85
Which of the following has activity at the Mu opioid receptor:
- M3G
- M6G
- Norfentanyl
- Paracetamol
What is the extracellular concentration of K+ in a unit of Packed Red Blood Cells after storage for 42 days?
- 3-5mmol/L
- 5-10mmol/L
- 10-15mmol/L
- >15mmol/L
Which of the following insulins has the fastest onset?
- Aspart
- Isophane
- Glargine
- Levemir
Which immune cells are involved in recognising and killing cells that express low levels of MHC class 1?
- Cytotoxic T lymphocytes
- Neutrophils
- Natural Killer Cells
- B lymphocytes
Carvedilol is a non-selective beta blocker with action on which other receptor?
- Alpha 1 antagonism
- Alpha 2 agonism
- Beta 2 agonism
- Beta 3 antagonism
What is the percentage of total body water for an adult female?
- 50%
- 60%
- 70%
- 80%
What process converts Dopamine to Noradrenaline?
- Hydroxylation
- Decarboxylation
- Methylation
- Acetylation