July 22nd, 2013
Selections from Richard Lehman’s Literature Review: July 22nd
Richard Lehman, BM, BCh, MRCGP
CardioExchange is pleased to reprint selections from Dr. Richard Lehman’s weekly journal review blog at BMJ.com. Selected summaries are relevant to our audience, but we encourage members to engage with the entire blog.
JAMA 17 July 2013 Vol 310
Vasopressin, Steroids, and Epinephrine and Neurologically Favorable Survival After In-Hospital Cardiac Arrest (pg. 270): There are three papers in this week’s JAMA which would make good teaching material for a course on critical reading. The first is a randomised, double-blind trial of an intervention for in-hospital cardiac arrest, carried out in three large Greek hospitals. The “placebo” was epinephrine (adrenaline) in saline, and the “active” intervention was combined vasopressin-epinephrine and methylprednisolone: “Vasopressin and methylprednisolone were prepared in study center pharmacies in identical, preloaded, 5-mL syringes and placed along with epinephrine ampules in boxes bearing patient codes. At the time of patient enrollment, a box was opened and study drugs were injected intravenously according to protocol. Drug injection was followed by 10 mL of normal saline.” I hope the crash team understood what they were doing because I’m not quite clear from this description. And given the small differences in survival rates, a few mistakes could make a large difference in the odds ratios for return of spontaneous circulation and survival to discharge. So if you like doing maths in the summer heat, you could go on and work out the actual potential differences; but I have already spent too long on a study which at best needs replicating before it changes practice.
Association Between Duration of Overall and Abdominal Obesity Beginning in Young Adulthood and Coronary Artery Calcification in Middle Age (pg. 280): Cardiovascular disease is undergoing a very steep decline in most developed countries, but as we are told every day, this might go into reverse as the current generation of obese young individuals reaches late adulthood. I like studies which challenge orthodoxy, but here we have an observational report which just provides weak surrogate support for the “obesity time-bomb” hypothesis. People who joined the CARDIA study between the ages of 18 and 30 were not obese, but 40% of them became so over the following 25 years. They each had a coronary calcium score done at 15 years and at 20 or 25 years. You can examine the statistics for yourself: there is a slight added risk of coronary calcium score progression according to years of obesity. What does this tell us? That some useful knowledge might emerge from this cohort if we wait for real events to happen.
BMJ 20 July 2013
NSAIDs: A useful Therapeutics review looks at non-steroidal anti-inflammatory drugs. Each article of this kind gives slightly different odds for GI bleeds and cardiovascular harm from specific drugs, but this one is very well referenced and is bang up to date, so I believe it. There is no excuse for prescribing long-term diclofenac in the elderly. There is no excuse ever for prescribing any NSAID at any dose to anyone with heart failure. That little bit of naproxen or ibuprofen can tip them into renal failure, if it doesn’t send them to hospital with pulmonary oedema: just don’t do it. I wish these messages came out even more strongly in this article. And I also wish they were clearer about what risk—if any—ibuprofen carries for people with a diagnosis of asthma.