MCAI SOE 9th March 2022

Pharmacology + Physics

1. Receptor
a. What is a receptor?
b. Table to fill up
c. Affinity - define.
d. Potency vs efficacy, give an example for each.
e. What is unique about buprenorphine?

2. LA
a. Compare and contrast ester and amides
b. What is pKa
c. How does LA work
d. EMLA - what is it?
e. Adrenaline is added into LA to prolong its effect, what does 1:100,000 and 1:200,000 means in terms of mg/ml and mcg/ml
f. List 2 clinical indications of LA other than regional block

3. Volatile
a. Factors affecting rate of action of volatile agent
b. Define MAC?
c. Factors increasing and decreasing MAC
d. Meyer-overton theory
e. Define concentration effect
f. Define second gas effect

4. Antihypertensives
a. Classify CCB and give example of each [6m]
b. RAAS mechanism + How does ACE-i work + side effect? [8m]
c. What is the evidence base for ACE-i in terms of its clinical indication. List two [2m]
d. Difference between ARBs and ACEI?
e. What is unique about angiotensin receptor neprilysin inhibitor (ARNI)?

5. Intensivist using ultrasound for TOE
a. What is sound wave? Characteristics of sound waves. [5 marks]
b. Relationship between velocity, wavelength and frequency. How can this be applied clinically? [3 marks]
c. 3 components of ultrasound machine. Briefly explain the MOA (3+3 marks)
d. What are the physical properties that affect the image of ultrasound?

6. Heat loss under GA
a. What is temperature? SI unit?
b. Mechanisms of heat loss under GA from highest to lowest?
c. How to prevent heat loss under GA in OT?
d. How does a thermistor work?
e. Some don’t know what theory/ law - Please help



Physio + Physics

1. Hb structure
a. What is Hb, how does O2 bind to Hb
b. Describe Cooperative binding in detailed [5 marks]
c. Clinical significance of ODC significance
d. Causes of right and left shift of ODC
e. What does P50 signify?
f. Label the above diagram, A is what conformation, B is what conformation. Label the 4 x O2 and 2,3-DPG

2. Valsalva manoeuvre
a. What is valsalva maneuvre
b. What was valsalva manoeuvre initially used for?
c. How to perform valsalva manoeuvre in conscious vs patient under GA?
d. What happens in phase 1 and phase 2 (6 marks)
e. Common uses of Valsalva nowadays? Need to list 4
f. What differences does it make for pregnant ladies (CVS changes)?

3. Stomach
a. List 4 functions of stomach
b. List 4 functions of HCL
c. Which cell produces HCl? Where are they found? [2m]
d. What stimulates HCl production? [3m]
e. Factors delaying gastric emptying - physiological & pharmacological
f. Why is the acidic environment in the stomach important?
g. If vagus nerve is denervated, would stomach emptying be increased or delayed? [1 mark]

4. Oculocardiac reflex
a. What 2 factors stimulate it and what's the anaesthetic concern
b. Label the nerve, pathway, nucleus, what type of nerve/nucleus/ganglion etc. [8m]
c. Name the CN5 and cn10 nucleus
d. What to do if bradycardia happens?
e. What to do if initial management not working
f. How to anticipate for oculocardiac reflex in high risk patient (eg. children with strabismus surgery)

5. Pressure, force (basically whole question taken from Masterpass physio/physics chapter 55 pg 164)
a. What is pressure? SI unit. What is force? SI unit. [3m]
b. 5 Other units of 1bar [4m]
c. Gas pressure (O2, air, N2O). [4m] *Need to know how to convert the units* - Pipeline pressure - Cylinder pressure - Pressure at common gas outlet
d. Are you more likely to dislodge a blockage in a cannula when using a 2 or 20ml syringe. What is clinical significance of using a smaller syringe?
e. Difference between partial and total pressure. Use a law to describe it
f. Atmospheric pressure and partial pressure [I don’t understand the question]

6. Flow
a. What is flow? Mathematical representation of flow
b. Component of ambu bag (5 marks)
c. Describe a clinical scenario to apply all components of Hagen Pouissle equation
d. What is laminar flow? Equation
e. What is turbulent flow? Reynold number that represent turbulent flow

Special thanks to Lim WY et. al.