Written by Shannon Markus
Spoon Feed
This meta-analysis supports targeting normal oxygen and carbon dioxide levels after cardiac arrest, but evidence is still limited, and ideal targets remain uncertain.
Shoot for normal
The International Liaison Committee on Resuscitation, Basic Life Support, and Advanced Life Support Task Forces sponsored this systematic review and meta-analysis, which updates evidence on oxygen and carbon dioxide targets after post-arrest ROSC. Both randomized and non-randomized controlled trials published after August 2019 were reviewed. The review addressed the question: “In adults and children with sustained ROSC, does targeting specific oxygenation or ventilation goals, compared to no or alternative targets, improve outcomes such as survival or functional recovery?” Meta-analyses found no differences in survival or favorable functional outcomes when comparing restrictive to liberal oxygen targets in either setting. There was also no difference in outcomes when comparing mild hypercapnia to normocapnia. The certainty of evidence was rated as low to moderate. While the study has multiple strengths, limitations include heterogeneity in target thresholds across studies, variability in outcome definitions, and the limited number of high-quality randomized trials for specific PaO₂ and PaCO₂ ranges. Ultimately, while current evidence supports avoiding extreme oxygen and CO₂ levels, optimal targets remain uncertain and warrant further large-scale trials.
How does this change my practice?
This review reinforces the importance of avoiding hypoxemia and hypocapnia after ROSC, as both are associated with worse outcomes. I’ll aim for normoxia (SpO₂ 94–98%) and normocapnia (PaCO₂ 35–45 mmHg) after ROSC, while recognizing that there is no clear benefit to targeting hyperoxemia or permissive hypercapnia. These guidelines are largely unchanged from 2020, and vigilant early ventilator management in the ED remains critical to optimizing neurologic outcomes.
Source
Oxygen and carbon dioxide targets after cardiac arrest: an updated systematic review. Resuscitation. 2025 Jun;211:110620. doi: 10.1016/j.resuscitation.2025.110620. Epub 2025 Apr 23. PMID: 40280356
