Blood-Pressure Management in Post-Cardiac Arrest Care: A Review of the BOX Trial

Abstract

This trial examined the optimal mean arterial blood pressure (MAP) target for comatose survivors of out-of-hospital cardiac arrest. In a double-blind, parallel-group design, the study enrolled Danish ICU patients who had a sustained return of spontaneous circulation (ROSC) after cardiac arrest. Participants were randomized to a higher MAP target (> 77 mmHg) or a standard MAP target (> 63 mmHg). Temperature control was maintained at 36°C for 24 hours, with mechanical ventilation and sedation. Neurological outcomes were assessed by attending physicians. The intervention protocol adopted a three-stage approach for MAP achievement, utilizing volume resuscitation, norepinephrine, and dopamine infusion as needed. The pharmacologic circulatory support was quantified using the vasopressor–inotropic score. The study concluded that there was no significant difference in the rates of death or severe disability between the two MAP target groups, suggesting that a higher MAP target does not improve the neurological outcome. The strengths of the trial include its methodological rigor and low attrition rate, with limitations related to its generalizability due to the single-country, two-centers setup.