24 Mar, 14 | by BMJ
NEJM 20 Mar 2014 Vol 370
1091 Please follow these instructions carefully: 1. Remove half of the skull, taking care to ensure you have chosen the appropriate side. 2. Repair the dura over the swollen brain and replace the scalp. 3. Wrap the removed skull and place in a refrigerator, choosing a shelf free of food items. 4. When the brain has returned to normal size, replace the half skull with care to ensure a good fit. That’s my idea of a hemicraniectomy, though I may have got some details wrong. I leave these things to others, like the neurosurgeons of Heidelberg, Ulm, Berlin, Leipzig and Dresden who conducted the DESTINY II trial. Hemicraniectomy was performed on 49 patients of mean age 70 for malignant middle-cerebral-artery infarction, i.e. total MCA occlusion causing unilateral massive brain oedema. Compared with 63 controls, these patients showed a much higher rate of survival without severe disability, though the majority of survivors still needed assistance with most bodily needs.
1111 Another thing I don’t get to do very often is treat hepatitis E in solid organ transplant recipients. Though if I did, I would know what to do: give them ribavirin at 8mg per kilogram of body weight per day for three months. Simple as that, according to this French trial.
1121 And if I ever ventured into the scary places where premature babies are kept alive amongst a tangle of machinery, I would be glad to hear the hum of high frequency oscillatory ventilators. In a long term follow up of a randomized trial involving children who had been born extremely prematurely, those who had undergone HFOV, as compared with those who had received conventional ventilation, had superior lung function at 11 to 14 years of age.
1138 Ah, and now for something I have actually done: the Epley manoeuvre for benign positional vertigo. I have only done it on my wife, who does not have BPV; but I was expecting to see a patient with BPV the next day. It is amazing how many versions of this simple manoeuvre/maneuver you can find on YouTube. I could have spent an entire day subjecting my lovely spouse to various indignities of head movement and position change. And then, I learn from this review article, there is another procedure called Semont’s maneuver which is also designed to reposition canaliths in the posterior canal. My greatest success however has come from the following procedure: (a) identify a young colleague who has been taught the manoeuvre properly (b) admire this person and praise her/his skill (c) agree that all patients you diagnose with BPV should see this person and no other.
JAMA Intern Med
OL Almost all the deep venous thromboses we see in normal practice are in the legs, but in critically ill adults, nonleg venous thrombosis is not rare, despite the use of thromboprophylaxis. It is a particular risk in cancer patients. I might not have singled out this Australasian ICU study for comment, but I could not resist the title of the accompanying commentary piece “Upper Extremity Deep Vein Thrombosis: A Call to Arms.”
JAMA 19 Mar 2014 Vol 311
1117 In the previous item, we encountered the new adjective “nonleg.” In this one, which is also about venous thromboembolism, we encounter “nonhigh.” It applied to the pre-test probability of a pulmonary embolism in a cohort of nonyoung European patients. The test, as you might expect, is D-dimer, and the rule, as you may already know, is to take the age of the patient and multiply it by ten to get the cut-off which excludes PE in patients with a low pre-test probability. So if you are 63, your cut-off is 630 μcg/L, and under that your risk of having a PE goes from nonhigh to practically nonexistent. This study was carried out at 19 centres in Belgium, France, the Netherlands, and Switzerland and confirmed this simple principle. Nonbad.
1150 Last week, an array of medical luminaries contributed to a Lancet paper extolling the merits of novel fixed-dose oral anticoagulants over warfarin in atrial fibrillation. I didn’t mention that many had ties with the manufacturers of these agents because that almost goes without saying. Here is a JAMA Clinical Evidence Synopsis on much the same topic—though it covers Factor Xa inhibitors only—by two authors who have only one slight industry connection between them. It reaches the same conclusion.
Lancet 22 Mar 2014 Vol 383
1041 Anastrozole is the kind of drug every company craves: it needs to be taken for long periods by large numbers of people, and its indication has now crept to include a really vast market—all women at increased risk of breast cancer. Unfortunately for AstraZeneca, its patent expired four years ago. Not, however, before they had helped to fund the IBIS II double-blinded randomized trial of anastrozole versus placebo in women at a greater than 5% risk of developing breast cancer within 10 years. The actual five year incidence of breast cancer in the placebo group was 4%, so the score they used was conservative. In the active group it was 2%.
1049 Tafenoquine, by contrast, may seem like the kind of drug no company wants: it cures with a single dose. But the disease it cures poses a risk to 40% of the world’s population, so GlaxoSmithKline must be quite pleased. They also run the Medicines for Malaria Venture, and this drug should give them great publicity—well-deserved if they make it available at low cost to those who need it most. Plasmodium vivax malaria rarely kills but is a very common cause of debility wherever it is endemic, and it has an annoying habit of lying dormant and then coming back, as in the retired Indian colonels who populate a certain kind of novel. That’s supposed to be the reason gin and quinine tonic became popular in the empire. “By Jove, old boy, you can throw away that quinine now they’ve got this tafenoquine. One dose and you’re sorted.” “I don’t want to be sorted, damn you. What else will I put in me gin? And what have you done with it, Singh?”
1059 Two of the great truths of medicine are that levels of blood sugar are observationally related to cardiovascular risk, and that levels of physical activity, by contrast, are associated with decreased cardiovascular risk. Factor the two together and what do you find? “In individuals at high cardiovascular risk with impaired glucose tolerance, both baseline levels of daily ambulatory activity and change in ambulatory activity display a graded inverse association with the subsequent risk of a cardiovascular event.” If this comes as news to you, you need to get out more.
1068 Here is a review with the title “Pathophysiology and treatment of type 2 diabetes: perspectives on the past, present, and future.” Do read it if you can get access to it, but only in order to remind yourself of how little things have changed since these words were written: “In general, the treatment of mature diabetics would seem to be an example of the large-scale use of ineffective and possibly dangerous therapies in a particularly inefficient way. The cause of the sad situation seems to be the assumption that if some biochemical parameter is abnormally distributed in a defined group of people, “normalizing” the distribution must do more good than harm. In mature diabetics it may well be that the wrong parameter is being altered.” A.L. Cochrane Effectiveness and Efficiency 1973.
1084 The next review is called “The many faces of diabetes: a disease with increasing heterogeneity.” That would not be my choice of title. Why not call it “Diabetes: heterogeneous diseases with a single label”? After all, diabetes is scarcely more heterogeneous now than it has ever been; it’s just that diabetes specialists are beginning to wake up to the fact. Let’s hope they may finally be recovering from “diabetologist retinopathy”—a condition which frequently blinds people to what is staring them in the face.
BMJ 22 Mar 2014 Vol 348
It is hard to conceive of a civilized diet that does not give high honour to fried food. The cover of the BMJ rightly celebrates the deep fried potato, a most delicious product. Served in mountainous quantities, however, it is undoubtedly responsible for obesity in the American population. This seems to be reflected in the food diaries of people in the two big US health professionals’ cohort studies. Add some genomics and you have a perfect blend of meaningless generalities about frying pans, genes and obesity.
The only reliable way to eat good food is to cook it yourself. People without the time or facilities to do this are likely to eat a lot of rubbish in the form of take-away meals. This way they will become fat without experiencing the pleasures which should properly accompany such a process. A study from Cambridgeshire appears to lend credence to my prejudices, but I would hesitate to go as far as the authors and suggest planning restrictions on take-away outlets near workplaces. Food snobbery I can condone, but I could never become a public health physician.
An interesting study from Denmark looks at the data association between macrolide antibiotics and the risk of hypertrophic pyloric stenosis in infants. Give a baby a macrolide in the first two weeks of life, and you increase the risk of HPS 30-fold. Any time from then up to 120 days, you still run a risk, but it gets less all the time. Giving the mother a macrolide in the last 12 weeks of gestation also increases risk by 70%, but since the incidence of HPS is now less than 1 in a 1000, in absolute terms this is only a small amount. The principal culprit is erythromycin.
Plant of the Week: Azara microphylla
For two weeks of the year—these being they—this small tree bears innumerable small yellow flowers beneath its leaves, which carry a heavenly scent of vanilla over a wide space. Breathing gusts of cold March air laden with vanilla used to be one of the chief joys of early spring for us, until we had to cut down our tall lanky wall-grown tree to make way for a house extension.
Vanillin is a fairly simple aromatic chemical which is quite widely found among plants, but the azara scent also has tones of honey which make it a sort of olfactory dessert course, unlike any other garden scent.
For the rest of the year your azara will give pleasure from its tiny evergreen leaves spread along slender branches. The variegated form is particularly handsome.