Oxygen therapy is widely used for patients with acute myocardial infarction (AMI). However, there is uncertainty about its safety and benefits. The aim of this study is to perform a systematic review and meta-analysis to assess the effectiveness and safety of oxygen therapy for patients with AMI. We searched MEDLINE, CINAHL, EMBASE, Cochrane Central Register of Controlled Trials from 1 January 1967, through 31 December 2017. We included randomized controlled clinical trials that used oxygen therapy for patients with suspected or confirmed AMI less than 24 h of symptoms onset. Hyperbaric and aqueous oxygen therapy trials were excluded. A total of six randomized controlled clinical trials with 7190 individuals were included in this meta-analysis. Compared with no oxygen group, oxygen therapy did not reduce the risk of all-cause mortality [pooled risk ratio (RR): 1.06, 95% confidence interval (CI): 0.56-2.02, P=0.19], recurrent myocardial infarction (pooled RR: 1.57, 95% CI: 0.88-2.80, P=0.18), and pain (pooled RR: 0.97, 95% CI: 0.82-1.14, P=0.25). In this meta-analysis, oxygen inhalation did not benefit patients with AMI with normal oxygen saturation.

Li, Huang, Feng (2018). Oxygen therapy for patients with acute myocardial infarction: a meta-analysis of randomized controlled clinical trials. Coronary artery disease, 2018 Dec;29(8):652-656. https://www.ncbi.nlm.nih.gov/pubmed/30260807