Oxford Handbook of Clinical Medicine 10th Edition
This is the first edition of the book without either of the original authors—Tony Hope and Murray Longmore. Both have now moved on to do other things, and enjoy a wellearned rest from authorship. In this book, I am joined by a Nephrologist, Gas-troenterologist, and trainees destined for careers in Cardiology, Dermatology, and General Practice. Five physicians, each with very diff erent interests and approaches, yet bringing their own knowledge, expertise, and styles. When combined with that of our specialist and junior readers, I hope this creates a book that is greater than the sum of its parts, yet true to the original concept and ethos of the original authors. Life and medicine have moved on in the 30 years since the fi rst edition was published, but medicine and science are largely iterative; true novel ‘ground-breaking’ or ‘prac-tice-changing’ discoveries are rare, to quote Isaac Newton: ‘If I have seen further, it is by standing on the shoulders of giants’. Therefore, when we set about writing this edition we drew inspiration from the original book and its authors; updating, adding, and clarifying, but trying to retain the unique feel and perspective that the OHCM has provided to generations of trainees and clinicians.
We wrote this book not because we know so much, but because we know we remember so little…the problem is not simply the quantity of information, but the diversity of places from which it is dispensed. Trailing eagerly behind the surgeon, the student is admonished never to forget alcohol withdrawal as a cause of post-operative confusion. The scrap of paper on which this is written spends a month in the pocket before being lost for ever in the laundry. At diff erent times, and in inconvenient places, a number of other causes may be presented to the student. Not only are these causes and aphorisms never brought together, but when, as a surgical house offi cer, the former student faces a confused patient, none is to hand.
We aim to encourage the doctor to enjoy his patients: in doing so we believe he will prosper in the practice of medicine. For a long time now, house offi cers have been encouraged to adopt monstrous proportions in order to straddle the diverse pinnacles of clinical science and clinical experience. We hope that this book will make this endeavour a little easier by moving a cumulative memory burden from the mind into the pocket, and by removing some of the fears that are naturally felt when starting a career in medicine, thereby freely allowing the doctor’s clinical acumen to grow by the slow accretion of many, many days and nights.
Thinking about medicine
Paternalistic, irrelevant, inadequate, and possibly plagiarized from the followers of Pythagoras of Samos; it is argued that the Hippocratic oath has failed to evolve into anything more than a right of passage for physicians. Is it adequate to address the scientifi c, political, social, and economic realities that exist for doctors today? Certainly, medical training without a fee appears to have been confi ned to history. Yet it remains one of the oldest binding documents in history and its principles of commitment, ethics, justice, professionalism, and confi dentiality transcend time.
The absence of autonomy as a fundamental tenet of modern medical care can be debated. But just as anatomy and physiology have been added to the doctor’s repertoire since Hippocrates, omissions should not undermine the oath as a para-digm of self-regulation amongst a group of specialists committed to an ideal. And do not forget that illness may represent a temporary loss of autonomy caused by fear, vulnerability, and a subjective weighting of present versus future. It could be argued that Hippocratic paternalism is, in fact, required to restore autonomy. Contemporary versions of the oath often fail to make doctors accountable for keeping to any aspect of the pledge. And beware the oath that is nothing more than historic ritual without accountability, for then it can be superseded by per-sonal, political, social, or economic priorities:
Cardiovascular medicine
Ischaemic heart disease (IHD) is the most common cause of death worldwide. Encouraging cardiovascular health is not only about preventing IHD: health entails the ability to exercise, and enjoying vigorous activity (within reason!) is one of the best ways of achieving health, not just because the heart likes it (BP, ‘good’ high-density lipoprotein (HDL))—it can prevent osteoporosis, improve glucose tolerance, and augment immune function (eg in cancer and if HIV+ve). People who improve and maintain their fi tness live longer: age-adjusted mortality from all causes is reduced by >40%. Avoiding obesity helps too, but weight loss per se is only useful in reducing cardiovascular risk and the risk of developing diabetes when combined with regular exercise. Moderate alcohol drinking may also promote cardiovascular health.
Hypertension is the chief risk factor for cardiovascular mortality, followed by smoking. Giving up smoking, even after many years, does bring benefi t. Simple ad-vice works. Most smokers want to give up. Just because smoking advice does not always work, do not stop giving it. Ask about smoking in consultations—especially those regarding smoking-related diseases.
• Ensure advice is congruent with the patient’s beliefs about smoking.
• Getting patients to enumerate the advantages of giving up motivation.
• Invite the patient to choose a date (when there will be few stresses) on which he or she will become a non-smoker.
• Suggest throwing away all accessories (cigarettes, pipes, ash trays, lighters, matches) in advance; inform friends of the new change; practise saying ‘no’ to their off ers of ‘just one little cigarette’.
• Nicotine gum, chewed intermittently to limit nicotine release: ≥ ten 2mg sticks may be needed/day. Transdermal nicotine patches may be easier. A dose in-crease at 1wk can help. Written advice off ers no added benefi t to advice from nurses. Always off er follow-up.
• Varenicline is an oral selective nicotine receptor partial agonist. Start 1wk be-fore target stop date and gradually increase the dose. SES: appetite change; dry mouth; taste disturbance; headache; drowsiness; dizziness; sleep disorders; ab-normal dreams; depression; suicidal thoughts; panic; dysarthria.
• Bupropion (=amfebutamone) is said to quit rate to 30% at 1yr vs 16% with patches and 15.6% for placebo (patches + bupropion: 35.5%): 1 consider if the above fails. Warn of SES: seizures (risk <1:1000), insomnia, headache.
Lipids and diabetes (pp690, 206) are the other major modifi able risk factors. The QRISK2 score (www.qrisk.org) is used in the UK to integrate a patient’s diff erent car-diovascular risk factors in order to predict future cardiovascular health.2 It can be used as part of a consultation on lifestyle factors to show patients that address-ing certain risk factors (eg smoking, BP) will reduce their risk of MIs and strokes.Apply preventive measures such as healthy eating (p244) early in life to maxim-ize impact, when there are most years to save, and before bad habits get ingrained.
Chest medicine
The lungs provide a vital physiological function in allowing gas exchange, but are also at the vanguard of a constant battle between host, pathogens, and pollutants. Respiratory medicine exemplifi es how careful epidemiology, science, and randomized controlled trials have revolutionized our understanding of com-mon diseases, leading to preventative measures and eff ective treatments. How-ever, the importance of poverty and general improvements in public health cannot be underestimated. Rates of TB in the UK declined well before the introduction of BCG vaccination and streptomycin, largely due to improvements in sanitation and less dense living conditions. Public health campaigns and taxation have helped lower smoking rates, although reductions in lung cancer will lag behind for many years.
Endocrinology
• Defi ne a syndrome, and match it to a gland malfunction.
• Measure the gland’s output in the peripheral blood. Defi ne clinical syndromes associated with too much or too little secretion (hyper- and hypo-syndromes, respectively; eu- means normal, neither nor , as in euthyroid). Note factors that may make measurement variable, eg diurnal release of cortisol.
• If suspecting hormone defi ciency, test by stimulating the gland that produces it (eg short ACTH stimulation test or Synacthen® test in Addison’s). If the gland is not functioning normally, there will be a blunted response to stimulation.
• If suspecting hormone excess, test by inhibiting the gland that produces it (eg dexamethasone suppression test in Cushing’s). If there is a hormone-secreting tumour then this will fail to suppress via normal feedback mechanisms.
• Find a way to image the gland. NB: non-functioning tumours or ‘incidentalomas’ may be found in health, see p224. Imaging alone does not make the diagnosis.
• Aim to halt disease progression; diet and exercise can stop progression of im-paired fasting glucose to frank diabetes. 1, 2 For other glands, halting progression will depend on understanding autoimmunity, and the interaction of genes and environment. In thyroid autoimmunity (an archetypal autoimmune disease), it is possible to track interactions between genes and environment (eg smoking and stress) via expression of immuno logically active molecules (HLA class I and II, adhesion molecules, cytokines, CD40, and complement regulatory proteins). 3 Endocrinologists love this reductionist approach, but have been less successful at understanding emergent phenomena—those properties and performances of ours that cannot be predicted from full knowledge of our perturbed parts. We understand the diurnal nature of cortisol secretion, for example, but the science of relating this to dreams, the consolidation of memory, and the psychopathology of families and other groups (such as the endocrinology ward round you may be about to join) is in its infancy. But as doctors we are steeped in the hormonal lives of patients (as they are in ours)—and we may as well start by recognizing this now. For those doing exams
‘What’s wrong with him?’ your examiner asks, boldly. While you apologize to the patient for this rudeness by asking, ‘Is it alright if we speak about you as if you weren’t here?’, think to yourself that if you were a betting man or woman you would wager that the diagnosis will be endocrinological. In no other disci-pline are gestalt impressions so characteristic. To get good at recognizing these conditions, spend time in endocrinology outpatients and looking at collections of clinical photographs. Also, specifi c cutaneous signs are important, as follows. Thyrotoxicosis: Hair loss; pretibial myxoedema (confusing term, p218); onycho-lysis (nail separation from the nailbed); bulging eyes (exophthalmos/proptosis). Hypothyroidism: Hair loss; eyebrow loss; cold, pale skin; characteristic face. You might, perhaps should, fail your exam if you blurt out ‘Toad-like face’. Cushing’s syndrome: Central obesity and wasted limbs (=‘lemon on sticks’ see fi g 5.2); moon face; buff alo hump; supraclavicular fat pads; striae. Addison’s disease: Hyperpigmentation (face, neck, palmar creases). Acromegaly: Acral (distal) + soft tissue overgrowth; big jaws (macro- gnathia), hands and feet; the skin is thick; facial features are coarse. Hyperandrogenism (): Hirsutism; temporal balding; acne. Hypopituitarism: Pale or yellow tinged thinned skin, resulting in fi ne wrinkling around the eyes and mouth, making the patient look older.
