No evidence for benefit of oxygen in acute myocardial infarction

Clinical Question: How effective is routine inhaled oxygen therapy for patients with acute myocardial infarction (AMI)?

Bottom line: There is no conclusive evidence from randomised controlled trials to support the routine use of inhaled oxygen in patients with AMI. There was no difference in analgesic use between the oxygen group and the air groups (room air breathed naturally or via a face mask). Of those who died, nearly 3 times as many people known to have been given oxygen died compared with those known to have been given air.

Caveat:The evidence in this area is sparse, of poor quality and predates advances in reperfusion techniques and trial methods. The evidence available suggests harm but lacks power, so these results could be due to chance.

Context: Oxygen is widely recommended for patients with AMI yet a narrative review has suggested it may do more harm than good. Other systematic reviews have also concluded there is insufficient evidence to know whether oxygen reduced, increased or had no effect on the heart, ischaemia or infarct size.

Cochrane Systematic Review:Cabelo JB et al. Oxygen therapy for acute myocardial infarction. Cochrane Reviews, 2010, Issue 6. Article No. CD007160. DOI: 10.1002/14651858.CD007160.pub2 This review contains 3 studies involving 387 participants