Today is done….

 

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Sunset Split, Croatia

To those of you who sat the ANZCA Primary Exam today – congratulations!!

You deserve a huge pat on the back.

I have posted several times now following the written paper and you can view my past posts at these links:

Well done today: there are worse things you could be doing

Phew – well done!

This too shall pass

It can be difficult to find peace after such a high stakes experience, but now is the time to look after yourselves and those around you, have a rest, do something fun and get ready to refocus your energy towards the viva.

I hope you all have a lovely and relaxing week, free from the burdens of study.

Best wishes for the exam

 

 

 

That time has arrived again….

A very warm and heartfelt best wishes for those of you sitting the exam tomorrow

You have done the hard work and now is the time to use your knowledge to its best effect.

Think positively – you are sitting this exam for a good reason.

The above series of photos is specifically designed to improve your sense of wellbeing heading into the exam- I hope it works!

(thanks to Google and Twitter for some of the images)

SAQ Exam Tip #4

The most important thing is to answer the question.

Another statement of the obvious. Thank you cynical anaesthetist!

How many times does the exam report contain the phrases “candidates didn’t address the question”, “candidates responses contained irrelevant information”, “candidates only addressed one part of the question”?

No matter how obvious or intuitive it is to answer the question, candidates still make this very basic error far too often. It would undoubtedly be the commonest problem I encounter while marking practice (and actual) SAQs.

Some examples again from recent papers:

Discuss the potential adverse effects of suxamethonium– Don’t tell me what sux is or classify it. Don’t tell me what it is used for or how it works. Tell me about adverse effects.

Outline the hazards associated with the use of CO2 absorbents within a circle breathing system and how the risks can be minimized- Don’t tell us how absorbents work. Don’t tell me why they are in a circle circuit, tell me what the hazards are. If the question has two parts to it like this one, then if you just answer one part you can’t hope to pass the question. Half of the marks are for detailing how the risks can be minimized. More commonly if a question has several components it will be explicitly detailed how many marks relate to each part.

Outline how hyperventilation may reduce intracranial pressure– this is not an invitation to write down everything you know about intracranial pressure or cerebral blood flow or bang on about the Monro-Kellie doctrine at the expense of everything else. Nor do you want to tell the examiner what propofol does to intracranial pressure.

Compare and contrast the pharmacology of ephedrine and norepinephrine– a profoundly depressing thing is to realise you’ve compared adrenaline and noradrenaline which wasn’t asked for…. Yet this error was still made.

Resist the temptation to define every component of the question. Sure, if you’re asked about CSHT then you need to define it but if you’re asked a question about adverse effects of opioids then you don’t need to tell me what opioids are or what they are used for. Cut to the chase.

Vallecula posted recently about making the most of the perusal time https://primarydailylo.wordpress.com/2018/08/03/reading-time-make-it-count/ and I strongly endorse those comments. Read the questions when you are fresh and underline the key components. Jot down the main points. Answer the question that is asked. Answer every question.

Good luck (not that luck has anything to do with it).

 

SAQ Exam Tip #3

SAQ chart

You are aiming for a 3.

I am not trying to be obtuse. I am referring to scoring 3 out of 5 for each SAQ. As you know we are marking SAQs out of 5 using a ‘holistic’ grid. A mark of 2 equates to 40% and 3 equates to 60%. The grids are non-linear; i.e. get 0 if you write nothing, get 1 if write a little that is mostly nonsense, get 2 if you write a few relevant points and no major errors or write lots of points including several with errors. A ‘3’ is a pass and contains most (not all) of the relevant (main) points for a SAQ without major errors. A ‘4’ represents a very good answer incorporating significant detail and we can all dream about getting 5s.

The diagram above (histogram) comes from the most recent exam report and makes a very important point. I suspect you would get a very similar diagram if you used data from previous exams. Although the majority of candidates achieve the invitation mark for the vivas (40% or average of 2/5 for each question), the majority of candidates don’t actually pass (>50%) this component of the paper. To pass the exam overall you need more than 50%, so if you go into the vivas with just over 40% you need to score almost 60% to pass. Of course the candidate who achieved a just adequate SAQ result is unlikely to over achieve in the vivas.  Consequently, most of those who failed the exam are in the 40-45% band above. If you go into the viva with 60% then you have an impressive buffer and I suspect none of those candidates failed the exam (I don’t know for sure but you get the gist).

You should get a 3 if you do all of the following:

  • Answer the question that was asked (see Tip #4 tomorrow)
  • Address the main points of the answer
  • Don’t commit major errors
  • Attempt every question on the paper- a blank paper is a crime
  • Have attempted the question before– practiced it as per Tip #1.

You should be able to fit all the pertinent points on one page of paper, micrographia notwithstanding. It can be helpful to ask yourself- what is the clinical relevance of this question? Why is the examiner asking this question of anaesthetic trainees?

SAQ Exam Tip #2

If you draw a diagram make it a good one.*

Another rather obvious tip from the cynical anaesthetist you might say. However, every year the same sorts of errors are made by candidates with regards to the use of diagrams.

Some SAQs will specifically ask for a diagram. In this case your diagram must be correct- draw a nice big diagram that takes up at least half the page and label it clearly. Unlike the vivas this is your chance to have axes and units all detailed correctly with the curves or waveforms looking precise. Remember you just have a black pen so practise differentiating multiple curves if that is relevant eg. washin curve for three different agents. If you are not sure about something then best leave it out. There are two good UK exam primer books that deal with every possible diagram you could be asked to do: Graphic Anaesthesia and Physics, Pharmacology and Physiology for Anaesthetists. Of course the diagram must ultimately come from one of the set texts. Many candidates compile a set of diagrams that are examined frequently. Equipment SAQs lend themselves to diagrams.

Most SAQs won’t specifically ask for a diagram but a diagram may enhance your answer. If the diagram is not directly relevant to the question and/or incorrect then it will detract from your response, not enhance it. If your diagram is illustrating just one point or could be replaced with a phrase or line of text then it is probably best to leave it out. Then you don’t detract from your response with a potentially incorrect or poorly drawn diagram that took you two minutes to draw.

A few examples of good and bad use of diagrams from recent papers:

Describe the respiratory response to hypoxaemia in both the awake and anaesthetized patient– a discussion of the hypoxic ventilatory response is clearly relevant here and producing the diagram of PaO2 vs Minute Volume ventilation is a good idea. The diagram is simple, easy to draw and can be used to address the question well- drawing the normal curve and showing how it changes in the presence of anaesthetic agents.

Describe the clinical effects of NSAIDs including mechanisms through which they exert these effects– seems candidates are incapable of answering a SAQ on NSAIDs without producing the generic flow diagram showing the synthetic pathway beginning with membrane phospholipids. Many candidates attempt to produce this diagram which is not relevant to the question and takes up half a page and precious time.

Discuss the potential adverse effects of suxamethonium– please don’t draw the structure of sux. Again, it is not relevant and quite hard to do. Similarly diagrams relating to its mechanism of action are similarly unnecessary and tedious to produce. This SAQ is best addressed by churning out a list of adverse effects with a few lines between each one and then going back filling in detail until your ten minutes are up.

Describe how the large daily volume of glomerular filtrate is altered by the kidney to form a relatively low volume of concentrated urine– while the counter current mechanism is certainly relevant to this question, producing a diagram that explains the mechanism is quite difficult to do. Many candidates attempted drawing nephrons and counter current loops which invariably didn’t enhance their answer. Better to briefly describe the mechanism- you get marks just for writing down the term!

Compare and contrast the action potential from the sinoatrial node and a ventricular myocyte- although it doesn’t explicitly ask for a diagram clearly producing accurate diagrams of the two potentials would go a long way to passing this question. This is a question where if you don’t know the correct diagram you are in a world of pain. Core topics expect and demand a good degree of detail.

Explain the reasons why a pulse oximeter may give incorrect readings– resist the temptation to talk about how a pulse oximeter works. Resist the temptation to trot out the Beer-Lambert law. Resist the temptation to draw the diagram of wavelength vs extinction coefficient or the oxygen dissociation curve or SpO2 vs R value. Although the different absorption spectra of different forms of haemoglobin are very relevant to causing ‘incorrect ‘readings, that is a tough diagram to get right. Better to list the reasons and briefly explain each point than devote yourself to reproducing an unreasonably difficult diagram.

*No diagrams were used (or harmed) in this post.

 

 

BT_RT 1.21 Outline the anatomy relevant to the drainage of pericardial fluid

Two LO’s relate to drainage of the pericardium but are not part of the Primary Exam:

  • BT_RT 1.36 Describe drainage of the pericardial space
  • SS_IC 1.96 Outline the management of oncology emergencies:  Due to primary disease, for example vena cava obstruction, acute cord compression, pericardial effusion

The subject of this post (BT_RT 1.21) relates to the background anatomy important for these LOs.

A situation in which you may encounter the need for pericardial drainage is treatment of tamponade due to malignant pericardial effusions. This may involve pericardiocentesis or the more permanent creation of a pericardial window.  Surgical approaches can be through the chest or abdomen.

Laparoscopic pericardial window was pioneered in Australia by John Corbet and in the early 1990’s in the regional Victorian town of Ballarat (according to a colleague from that hospital).  Here is the link to the reference. You might need to ask you friendly librarian to obtain a copy.

Anaesthetising patients for this procedure is challenging; not only do you need to deal with the cardiac tamponade but also the physiological effects of the laparoscopy.

Physiology of cardiac tamponade probably fits under BT_RT 1.2 and BT_RT 1.3 both related to shock and the physiological effects of laparoscopy is covered in two LOs: BT_PO 1.48 and IT_GS 1.8

Anyway, back to the subject of this post; your challenge is to be able to visualise and describe the anatomy.

I found it difficult to find any good anatomy textbook descriptions and images to help but it is worth looking in Anatomy for Anaesthetists 9e (Wiley) by Ellis & Lawson and Miller 8e Ch 67 both available on the ANZCA website.

There is plenty of instructional material online showing how to perform pericardiocentesis along with ultrasound images and videos from which you can gain an understanding of the anatomy.

For laparoscopic pericardial window I thought a video might be helpful. To orientate you, the surgery is performed using the same patient position and access ports as a laparoscopic cholecystectomy.

So watch this video and here are some questions:

  1. What is the structure in the lower part of the screen?
  2. What structure is at the top of the screen?
  3. What layers are traversed during this procedure?
  4. How much fluid is usually within the pericardium?  How much do you think was drained?
  5. What part of the heart is visible through the pericardial window at the end?

Anatomy for Vascular Access

BT_RT 1.20   Outline the anatomy relevant to vascular access in resuscitation: specifically for safe cannulation of antecubital, saphenous, jugular, and subclavian veins, and placement of intraosseous infusion devices.

 

Obtaining vascular access is a cornerstone of resuscitation, and colleagues from other specialties will call for an anaesthetist when access is very difficult. Your knowledge of venous anatomy needs to be excellent. With very difficult patients (e.g. morbidly obese, or small infants), ultrasound can be very helpful, but it is no substitute for knowing the anatomy.

The life-saving value of intraosseous devices is now well recognised (especially the Ez-IO drill). Do you know where to get hold of intraosseous devices in your hospital? Hopefully, you have them in your OR.

 

T / F  in the antecubital fossa, the median cubital vein usually continues proximally, running parallel to the long axis of the arm

T / F  the median cubital vein and the brachial vein are interchangeable terms for the same thing

T / F  the external jugular vein runs superficial to the sternomastoid muscle – it passes beneath the clavicle to join the subclavian vein

T / F  the great (long) saphenous vein can be cannulated just anterior to the lateral malleolus

T / F  fluids or drugs injected into the medullary cavity of a bone will rapidly enter the circulation via multiple connecting veins

T / F  intraosseous access can be obtained in the tibia – about 1 cm below the tibial tuberosity, on the flat medial  part of the bone where the skin covering is very thin

T / F  intraosseous access can be obtained in the proximal humerus – the greater tubercle is the point of insertion

SAQ Exam Tip #1

The written exam is fast approaching. I didn’t need to tell you that! In this series of SAQ exam tips I want to focus on a few things in order for you the candidate to get the best possible results.  Most of these ‘tips’ have been mentioned in previous posts by my colleagues and they have certainly all been broached in the exam webinar. Regardless, I think it will be beneficial in the final lead up to the paper to have these tips in the forefront of your hippocampus.

The first tip is you must do lots of practice SAQs. Yes, this is stating the obvious but bear with me. Perusal of previous exam reports will demonstrate that many SAQs are repeated. SAQs that are done particularly poorly have a tendency of being asked again. There is very likely to be half a dozen physiology questions, half a dozen pharmacology questions, an anatomy question and an equipment question. There is only one stats question that has been asked of late and it has been asked several times so you should have a fantastic prepared answer for that one. If you haven’t attempted the SAQs for the last four exams (60 SAQs in all) then you are handicapping yourself.

When you are doing prac SAQs it is best to try and replicate exam conditions: ten minutes per question, don’t look at them prior, use a black pen only, take your watch off and have a clock on the wall to look at. I have a dozen sets of 6 question papers which I use with my trainees. Each paper takes one hour to do and because I have set them the trainee doesn’t know what the questions are. Almost as useful as doing the practice papers is getting them marked immediately after attempting the questions.  The feedback is invaluable.

  • What score did you get? (Tip #3 addresses this in more detail)
  • Did you actually answer the question? (Tip #4 addresses this in more detail)
  • Is it legible? Is it understandable?

If you have done a poor response then you need to go back to the books and compose a specimen answer for yourself.  Doing lots of SAQs will help find holes in your knowledge and hopefully inspire you to rectify them while the SAQ is still fresh in your head. In this week leading up to the exam most of you will have already done a considerable pile of prac SAQs. If you haven’t already done so I recommend getting a study partner/ friendly consultant/ your significant other to set a full practice exam (15 Qs) for you. Then get someone to mark it.

A full exam is 165 minutes long and quite exhausting. Doing a full practice exam helps test (apart from your knowledge) your time management skills, ability to prioritize and may find another little hole that you didn’t realise you had.

 

Calcium

BT_PO 1.72  Describe the function, distribution, and physiological importance of sodium, potassium, magnesium, calcium and phosphate ions

 

T / F  the calcium present in blood is 50% ionised, 40% bound to albumin, and 10% complexed with bicarbonate

T / F  hypercalcaemia can occur with a parathyroid tumour which secretes parathyroid hormone

T / F  hypercalcaemia can occur with bony metastases due to mechanical destruction of  bones which allows calcium to leach out **

T / F  hypercalcaemia can cause polyuria – this is due to inhibition of the Na-K-2Cl transporter, with reduced reabsorption of Na

T / F  hypercalcaemia can cause tetany – due to increased nerve excitability

T / F  hypercalcaemia can prolong the QT interval

References:
1. Guyton 12th ed Ch. 79
2. Ganong 24th ed Ch. 21 (regarding **, see page 384)

Vasopressin

BT_RT 1.18  With reference to cardiopulmonary resuscitation, describe the pharmacology of adrenaline, vasopressin, amiodarone and lignocaine

BT_RT 1.17  With reference to the management of shock, describe the pharmacology of vasopressors and inotropes, including: … vasopressin

 

T / F  vasopressin is the same thing as anti-diuretic hormone

T / F  vasopressin acts on vascular smooth muscle via a G protein coupled receptor, type V1a, which causes an increase in IP3, and increased calcium entry into the cell

T / F  a vasopressin infusion may be effective in refractory septic shock, refractory anaphylaxis, or the vasoplegia which occurs after cardiopulmonary bypass

T / F  vasopressin does not increase pulmonary vascular resistance

T / F  during CPR, a bolus of 40 U vasopressin has been used, although this is not recommended by ANZCOR as routine therapy

T / F  an ampoule of vasopressin contains 10 units in 1 mL

References:
1. Goodman & Gilman p.701-708
2. product information
3. ANZCOR and ILCOR resus guidelines
4. ANZCA anaphylaxis guidleines  http://www.anzca.edu.au/resources/endorsed-guidelines

Further discussion points:
– what is the difference between vasopressin and desmopressin?
– what are the uses of desmopressin?