The following is a summary of “Lower versus higher oxygen targets for out-of-hospital cardiac arrest: a systematic review and meta-analysis,” published in the October 2023 issue of Critical Care by Cheng et al.
Supplemental oxygen is commonly given to cardiac arrest patients, but the best oxygen level to aim for is unclear. Researchers started a retrospective study to evaluate the impact of lower versus higher oxygen targets on patients after out-of-hospital cardiac arrest.
They looked for the Cochrane Central Register of Controlled Trials, MEDLINE, and Embase, covering the period from inception to February 6, 2023. The focus was on randomized controlled trials that compared lower and higher oxygen targets in adults (aged ≥ 18 years) following out-of-hospital cardiac arrest. Independently, studies were reviewed, and data were gathered. The primary focus was the 90-day mortality rate after cardiac arrest. The testimony quality was assessed using the grading of recommendations assessment, development, and evaluation approach.
The results showed 7 randomized controlled trials involving 1,451 participants. A higher oxygen target, in contrast to a lower one, did not lead to a greater mortality rate (relative risk 0.97, 95% CIs 0.82 to 1.14; I2 = 25%). These findings stayed consistent in trial sequential, subgroup, and sensitivity analyses.
Investigators concluded that lower oxygen targets did not improve survival in cardiac arrest patients.