JOURNAL SNIPPETS

Lancet 4 Sep 2010 Vol 376
784 The palliation of terminal dyspnoea is a subject is interesting, mainly in the context of heart failure, where many patients are dyspnoeic without substantial reduction in oxygen saturation. Nevertheless they frequently get symptomatic benefit from inhaled oxygen, some to the point of becoming dependent on an immediate oxygen source. For years I heard some of the authors of this study discuss a blinded randomised trial of room air versus oxygen for such patients, not just with those with cardiac dyspnoea but with a range of terminal conditions. And here at last it is: a landmark in evidence-based palliative care, showing that room air works as well as oxygen over a period of a week. However, I can foresee major problems in real life: "Are you trying to kill him doctor? They've delivered a cylinder of compressed air, but Eric needs his oxygen. I told them to take it away."
http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(10)61115-4/abstract

BMJ 4 Sep 2010 Vol 341
491 A worthy attempt to meta-analyse the data that exist about the outcomes of nurse-led interventions to improve control of blood pressure. Nurses using algorithm-guided protocols show some success in the USA, especially when they are given prescribing powers. But just what are we doing in hypertension? A recent review I read suggested that it really takes 14 office readings to determine whether a change of treatment is needed. Most of what we do to our patients with raised blood pressure is probably futile, and we urgently need better primary care studies to tell us how to do better.
http://www.bmj.com/content/341/bmj.c3995.full

OXYGEN FOR HEART PATIENTS

Evidence unclear on oxygen use for heart attack

Overview: Coronary heart disease is the leading cause of death in the UK, accounting for a third of all deaths in people aged 35 and over. Myocardial infarction occurs when the flow of oxygenated blood in the heart is interrupted for a sustained period of time. Supplementary oxygen, delivered by a face mask or cannula, is often given to a patient with acute myocardial infarction (AMI) with the rationale that it may improve the oxygenation of the ischaemic myocardial tissue and reduce pain, infarct size and consequent morbidity and mortality.Current treatment: Current evidence neither supports nor refutes the routine use of oxygen for patients with acute myocardial infarction. It is biologically plausible that oxygen is helpful but it is also biologically plausible that it is harmful. NICE recommends oxygen should not be routinely administered to patients with acute chest pain of suspected cardiac origin, but that oxygen saturation levels should be monitored and used to guide its administration. SIGN guidance only recommends oxygen use in hypoxaemia

New evidence: A Cochrane systematic review (Cabello et al 2010 Jun 16;6:CD007160) found three randomised controlled trials comparing the outcomes in patients given oxygen to those given normal air to breathe. It examined whether there was a difference in death, pain and complications.The results reaffirm the current uncertainty of the role of oxygen in patients with myocardial infarction, and the authors call for a large, definitive randomised controlled trial on which clinical practice guidelines can be more confidently based.
Commentary: "The rapid assessment and treatment of a patient with a heart attack is drummed into most medical students very early on in their training. ABC: airway, breathing, circulation. Part of that resuscitation is the delivery of oxygen to patients with a heart attack, mainly due to the fact that the flow of oxygenated blood in the heart is stopped for a period of time."We have moved from one set of guidelines based on expert opinion to another set of guidelines with a different set of recommendations, but the research evidence has not changed. As this recent Cochrane review highlights, there is still no conclusive evidence from randomised controlled trials to support the routine use of inhaled oxygen in patients with acute heart attack."As the reviewers rightly state, we urgently need a large scale trial to unpick the uncertainty. Potentially, if further research addresses the uncertainty in one direction or another, implications for public health and cost efficiency could be huge." - Carl Heneghan, Director of thNHS Evidence - cardiovasculare Centre for Evidence Based Medicine, GP and clinical lecturer at the University of Oxford.
For more information on evidence relating to cardiovascular health visit .