Inhaled oxygen does not benefit patients with AMI
MedWire News: There is no conclusive evidence from randomized controlled trials to support the routine use of inhaled oxygen in patients with acute myocardial infarction (AMI), indicates a new Cochrane Systematic Review.
In fact, the review of available clinical trial data suggests that oxygen might actually be harmful to these patients.
Oxygen is widely recommended for patients with MI but there is conflicting evidence on whether this intervention improves outcomes for heart patients or actually causes further damage.
To determine if routinely giving oxygen to people with suspected and proven AMI does more good than harm, Juan Cabello (Alicante General University Hospital, Spain) and co-investigators reviewed the evidence from randomized controlled trials that compared outcomes in AMI patients given oxygen and those given normal air to breathe.
The researchers identified three trials involving 387 patients, of whom 14 died. In an intention to treat analysis, patients who received oxygen had a 2.88-fold increased risk for death compared with those who received air. Among patients with confirmed AMI, oxygen use was associated with a 3.03-fold increased risk for death compared with air.
Although the results appear to suggest giving oxygen could do more harm than good, “the small number of deaths recorded meant that this could be a chance occurrence,” the authors stress.
Cabello and team also investigated whether administering oxygen reduced pain. They found that pain, measured by analgesic use, did not appear to be affected by oxygen use.
The researchers conclude that none of the three trials demonstrated that oxygen therapy in patients with AMI does more good than harm on clinical outcomes.
“Since the evidence suggests that oxygen may in fact be harmful, we think it is important to evaluate this widely used treatment in a large trial, as soon as possible, to make sure that current practice is not causing harm to people who have had a heart attack,” they add.
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By Laura Dean