Survivors of out-of-hospital cardiac arrest (OHCA), identified in a cohort study, face a higher risk of subsequent acute myocardial infarction (AMI) influenced by age and prior history, underscoring the need for preventive measures to enhance outcomes.

The following is a summary of “Combined effects of targeted blood pressure, oxygenation, and duration of device-based fever prevention after out-of-hospital cardiac arrest on 1-year survival: post hoc analysis of a randomized controlled trial,” published in the January 2024 issue of Critical Care by Meyer et al.

Researchers conducted a retrospective study to dissect the individual and synergistic impacts of “Blood Pressure and Oxygenation Targets in Post Resuscitation Care” (BOX) interventions on 1-year mortality in comatose patients.

They conducted the BOX trial, a randomized two-center study, where comatose patients after out-of-hospital cardiac arrest were assigned to 3 interventions upon admission, targeting a blood pressure of either 63 mmHg or 77 mmHg for arterial oxygenation of 9–10 kPa or 13–14 kPa,  implementing device-based fever prevention for the initial 24 hours at 36^° C and then either 12 or 48 hours at 37 ^° C, resulting in a total of 36 or 72 hours of temperature control. Randomization took place concurrently for all interventions. One-year follow-up tracked all-cause death occurrences using Cox proportional models, assessing interactions with the interventions as terms.

The results showed 789 patients in the low versus high blood pressure target intervention. The 1-year mortality rates were 35% (138 out of 396) and 36% (143 out of 393), with an HR of 0.92 (0.73–1.16), P=0.47. In the restrictive versus liberal oxygenation target intervention, the 1-year mortality rates were 34% (135 out of 394) and 37% (146 out of 395), with an HR of 0.92 (0.73–1.16), P=0.46. For device-based fever prevention for a total of 36 versus 72 hours, the 1-year mortality rates were 35% (139 out of 393) and 36% (142 out of 396), with an HR of 0.98 (0.78–1.24), P=0.89. No interaction occurred between interventions, and as a result, no combination of randomizations indicated distinct treatment effects.

They concluded that 1-year mortality remained unaltered by individual or combined BP, oxygen, and fever interventions in BOX trial patients.

Source: ccforum.biomedcentral.com/articles/10.1186/s13054-023-04794-y