1. Anatomy of the heart
- What are the three layers of the heart?
- Where is the atrioventricular node (AVN) and the sinoatrial node (SAN)?
- Describe the venous drainage of the heart
- How many leaflets does the mitral valve have?
- where does the left coronary artery/right coronary artery originate?
- What are the chordae tendinae and what are they joined to?
- What are the normal RV pressures?
- What is the normal left atrial pressure (LAP)?
You are shown an X-ray (angiogram):
- what is the arrow pointing to?
You have just anaesthetised a boxer for an MUA nose after a fight. You were unable to intubate him and had to use a laryngeal mask. You knocked off a crown during the attempt to intubate him. You are now about to see him on the ward to explain what has happened. He is very aggressive, threatening to sue, and wants the hospital to pay for dentistry.
Humidity: you are shown a photograph of a piece of equipment:
- What is it?
- Define relative humidity and absolute humidity (you are required to give a very precise definition - remember to mention and define pressure/temperature)
You are shown drawings (taken from Parbrook):
- Which of these drawings is the hair hygrometer?
- Which of these drawings is the Regnaults hygrometer?
- Which of these drawings is the wet/dry bulb hygrometer?
- How does the latter equipment work?
- Define the latent heat of evaporation
- How would you relate the readings on the thermometers to the humidity?
You have two gas samples, one at 20 degrees C, one at 37 degrees C; both have a relative humidity of 50%:
- which one has the highest absolute humidity?
You find a child collapsed and unresponsive. You have a bag and mask. You are alone. Please proceed with resuscitation.
- How long would you carry on giving basic life support?
- What would you do then?
You are shown a monitor (with questions on a sheet):
- What is the rhythm shown?
- Fill in the algorithm
You are given the history of a 20-year-old female who is involved in a road traffic accident. She has facial injuries. She was initially OK, but is now becoming drowsy, with severe facial swelling.
You are shown a computer screen with a 3D CT reconstruction of her skull on it:
This shows fractured right maxilla, fractured right zygoma, fractured right frontal bone (through frontal sinus). Comminuted fracture of the orbit. Answer the following true/false questions:
- This shows a LEFT zygomatic fracture
- The arrow points to the supraorbital foramen
- She is at risk of intracranial infection
- She is likely to require prolonged ventilation in the ITU
- She requires urgent transfer to a neurosurgical centre
- She is likely to suffer a left sixth cranial nerve palsy
- She requires speedy intubation as she is likely to become difficult later
You are shown graph of age (x-axis) versus height (y-axis) for children with scattered points on it. Answer the following true/false questions:
- the line of best fit has a gradient termed the regression coefficient
- the regression coefficient is denoted by the letter 'r'
- it is possible to have a correlation coefficient of 1.1
- it is possible to have a correlation coefficient of minus 0.7
- an 'r' value of 0.7 would be statistically significant
- it is customary to plot the dependent variable on the x-axis (abscissa)
- the coordinate (mean x, mean y) would lie on the line of best fit
- these data could be analysed using a non-parametric test
7. Physical examination
Examine this man's radial pulse and praecordium. You should not attempt to examine any other part of the cardiovascular system. Describe what you are doing as you go along.
Depending on your description of your actions, various questions will be asked; for example:
- What information can you get from the pulse?
- What would an irregular pulse mean?
- What would a collapsing pulse mean?
- Can you say anything else about the pulse?
- What would radial/radial delay denote?
- What is radial/femoral delay?
- What would you hear better by tilting the patient?
You are given the front half of a skull:
- What is the optic canal?
- What is the superior orbital fissure?
- What is the intracranial relationship of the optic nerve to the carotid artery?
- What happens to the fibres of the optic nerve when entering the skull?
- Do the medial fibres or the lateral fibres decussate?
- If you had a bitemporal hemianopia, where would the lesion be?
- What would be the most common cause of this?
- What is the intracranial length of the optic nerve?
- Where do the fibres of the optic nerve radiate out to?
- What is the length of the optic nerve in the orbit?
- What characteristics would the needle used for a retrobulbar block have?
- How long would it be?
- What are the bony landmarks?
- Where would the needle be directed towards?
- What are the complications of a peribulbar block (three wanted)?
9. History taking
You are about to meet a young woman whom you are to anaesthetise tomorrow for a subtotal thyroidectomy. Take a pre-anaesthetic history.
You are given a blood giving set:
- What is filtered by this?
- What is this filter used for?
- What is this type of filter called?
You are shown a white blood cell (WBC) filter:
- What common infectious agent is carried in WBCs?
- What percentage of the population have cytomegalovirus?
You are given an epidural filter:
- What is this used for?
- What does it filter?
- What is the pore size?
- How does it filter viruses?
You are shown a heat-moisture exchanger:
- What is this used for?
- Would it be appropriate for use in a 10 kg child breathing spontaneously?
You are asked to examine a microscope slide of a blood film, and see a red blood cell, a platelet and a staphylococcus aureus.
- Which is biggest?
- Which is smallest?
11. Machine check
You are asked to carry out an equipment check on an old machine with no pipelines, two Tec-5 vaporisers.
Possible faults include:
- O2 analyser not working
- CO2 missing, no blanking plug
- Both vaporisers had one O ring missing
- O2 failure alarm not working
You are presented with an ECG showing a ventricular paced rhythm. Answer the following true/false questions:
- The rate is 70-75
- The QRS duration is 0.12 seconds
- The t wave inversion is indicative of ischaemia
- The calibration spike is the usual 2 cm to 1 mv
- There is evidence of spontaneous atrial activity
- Bipolar diathermy would be contraindicated in this case
You are about to see a woman who is to have a mastectomy tomorrow. Take a pre-anaesthetic history.
Points that you should pick up: The patient has a hickman line and is on chemotherapy. She is allergic to eggs, seafoods, elastroplast and iodine. You discover that her sister has malignant hyperthermia, but the patient has been tested negative. She has had no problem with previous anaesthetics.
Clinical history: A 60-year-old man is due to undergo a transurethral resection of the prostate (TURP). He has a respiratory rate of 33 bpm and can speak six words before getting SOB. On vitalograph spirometry, he has an FEV1 of 0.3 L and FVC of 0.4 L. Answer the following questions:
- Does he have a normal FEV1/FVC ratio?
- Does he have primarily obstructive lung disease?
- Is this corrected to btps?
- He is due to have anaesthesia for elective upper abdominal surgery. Would this be precluded in this case?
- Would spinal anaesthesia for the TURP have no detrimental effect on respiratory function?
- Are his blood gases likely to be normal?
You are shown a model of a neck:
- Identify the thyroid cartilage
- Identify the cricoid
- Identify the cricothyroid membrane
- Describe how you would anaesthetise the skin for a cricothyroidostomy
- Describe step by step how you would use this equipment for a cricothyroidostomy
16. Measuring equipment
- What information is given by a pulse oximeter?
- How does a pulse oximeter work?
You are shown a Hb/O2 dissociation curve
- What is the pO2 at this point (90% saturation)?
- What is the point at 50% saturation called?
- What is the reason for measuring the p50?
You are shown graph of absorbance spectra for Hb/HbO
- What is the marked point? (isosbestic point)
- What does this trace signify? (blood pressure cuff going up and down)
- Can you give three reasons for inaccuracies?
17. Other recent OSCE questions
- Coeliac plexus anatomy
- Demonstration of how to do a cricothyroidotomy
- Checking a Bain circuit
- Thoracic surface anatomy: where to do an emergency then elective chest drain, intercostal blocks and the anatomy of the first rib
- What is wrong with the arterial line set? (no pressure bag, 5% dextrose, venflon with injecting port instead of arterial cannula, etc)
- Complete a cranial nerve examination and brief discussion on brainstem death testing
- Pre-operative assessment of a day-case patient for removal of wisdom teeth; the patient is needle phobic and had sustained a broken nose in the past
- Counselling a patient on the methods of pain relief following a cholecystectomy, with particular reference to PCAs (pros and cons of PCAs versus epidurals)