Giving oxygen to heart attack victims may do more harm than good
Wednesday 16 June 2010
Experts say urgent research is needed to establish whether the traditional medical practice of giving oxygen to people who have had heart attacks may actually put them at risk of dying – so doing more harm than good.
Heart attack patients are often given oxygen, in accordance with national and international guidelines. In the UK, ambulance service protocols and most local guidelines for treating heart attacks recommend that patients be given oxygen and nearly all nurses, doctors and paramedics do so. However, there is scant evidence that this intervention improves outcomes for heart patients and some evidence even suggests it may cause further damage.
The researchers undertook a highly sensitive search for all published studies of oxygen in heart attack combined data from three trials meeting stringent quality criteria in their study. Patients were either given pure oxygen or air to inhale in the 24 hours following the onset of heart attack symptoms. Of the 387 patients involved in the studies only 14 died, but of these, almost three times as many had inhaled oxygen as opposed to air.
Although the results appear to suggest giving oxygen could do more harm than good, the researchers say there is not yet enough data to be certain and are proposing a larger study to investigate the evidence.
Professor Tom Quinn, based at the Faculty of Health and Medical Sciences at the University of Surrey, said it is important to be certain. He commented: “Given the fact that this is such a widely used treatment, we think it is important that a large trial is conducted as soon as possible to make sure that giving oxygen is not causing any harm.”
Dr Juan Cabello, of the Alicante General University Hospital in Alicante, Spain, added: “It is truly amazing how we, as cardiologists, have been employing this treatment for so many years without solid evidence.”
A heart attack occurs when the flow of oxygenated blood to the heart muscle is interrupted. Each year more than 30 million people across the world have a heart attack, according to the World Health Organisation. In the UK, over 100,000 people a year die from Coronary Heart Disease with about a third dying from a heart attack.
The research has been conducted by a collaboration of researchers and clinicians at the University of Oxford, the University of Surrey, the University of Birmingham and the Alicante General University Hospital and Hospital Donostia, San Sebastián in Spain. It has been published in the internationally respected Cochrane Library.
Full citation:
Cabello JB, Burls A, Emparanza JI, Bayliss S, Quinn T. Oxygen therapy for acute myocardial infarction. Cochrane Database of Systematic Reviews 2010, Issue 6. Art. No.: CD007160. DOI: 10.1002/14651858.CD007160.pub2
Media Enquiries
Howard Wheeler, Press Office at the University of Surrey, Tel: +44 (0)1483 686141, or Email mediarelations@surrey.ac.uk
Video: Professor Tom Quinn explains
To find out more about this story, watch a video of Professor Tom Quinn.
