Drugs used to treat diabetes mellitus Commentary

Diabetes is common and the main clinical interest for anaesthetists lies in the maintenance of effective glucose homoeostasis. This is not, however, the focus of this question, which concentrates more on an understanding of intermediary metabolism. The range of drugs is expanding, but you will not be asked in any detail about newer agents such as the meglitinides and glitazones. You will, on the other hand, be expected to know about insulin and something about the well-established biguanides...

The sciatic nerve Commentary

The sciatic nerve is the largest peripheral nerve in the body and it is accessible from a number of sites. Sciatic nerve block provides good analgesia for much lower limb surgery, and the variety of possible approaches provides an appropriate test of applied anatomy. As always with questions which include practical procedures, it will help greatly the credibility of your answer if you can convince the examiner that you have undertaken some of these blocks. You will not, however, be expected to...

Direction the viva may take

You are likely to be asked about the anaesthetic implications of thyroid disease. Overt thyrotoxicosis and myxoedema are rare, but anaesthetic mismanagement of either condition may be disastrous. So even though the viva may have concentrated on basic endocrinology, make sure that you know the principles of clinical management. Airway problems All forms of thyroid disease may be associated with large goitres, which may extend retrosternally and cause airway problems. Hyperthyroidism The clinical...

Further direction the viva could take

You may be asked, almost as an aside, why patients with thyrotoxicosis develop proptosis, and why hypothyroidism is known as myxoedema. It will have (almost) no bearing on whether you pass or fail, but there is no point in becoming unnecessarily dejected by not knowing the answer to the final question of the section. Skin contains various proteins combined with polysaccharides, hyaluronic acid and chondroitin sulphuric acid. In hypothyroidism these complexes accumulate, and so promote water...

The viva

You may be asked to classify the degrees of obesity, before describing the physiological and anaesthetic implications. Classification The most widely used method of classifying obesity is the body mass index (BMI), which is determined by the weight (kg) divided by the square of the height (m2). A BMI of 18-25 is normal, 26-30 is overweight, 31-35 is obese, and over 35 is morbidly obese. There has recently been introduced the further category of 'super obesity' into which fall patients with a...