In-hospital cardiac arrest (IHCA) is a prominent cause of death worldwide, and studies show documented survival rates for IHCA ranging from 0% to 42%. [1][2][3][4] The high mortality rate of patients who initially achieve return of spontaneous circulation (ROSC) after cardiac arrest (CA) can be attributed to post-cardiac arrest syndrome, which includes myocardial dysfunction, systemic ischemia/reperfusion response, anoxic cerebral injury, and persistent precipitating pathology. 5 Several modifiable factors have been investigated in the search of clinical paths to optimize treatment. The role of supplemental oxygen post-CA has gained increased attention recently. A cohort study suggested early post-resuscitation hyperoxia as an independent predictor of poor neurological function. 6 Several observational studies, including two large meta-analyzes indicate hyperoxia after