In-hospital cardiopulmonary resuscitation with balloon occlusion of the descending aorta: protocol of the randomised controlled CPReboa study.

introductionCardiac arrest (CA) remains a major health burden with poor survival and poor neurological outcomes despite decades of advances in resuscitation science. Although high-quality cardiopulmonary resuscitation is essential, it provides only limited cerebral and coronary perfusion, and current strategies relying on high-dose epinephrine may adversely affect cerebral microcirculation. Resuscitative endovascular balloon occlusion of the aorta (REBOA) has emerged as a potential adjunct to improve coronary and cerebral perfusion without compromising microvascular blood flow. Although animal studies and small human case series suggest physiological and clinical benefits of REBOA in CA, randomised clinical trials are lacking. METHODS AND ANALYSIS: This prospective, randomised controlled, single-centre clinical trial investigates the effect of REBOA during the treatment of CA. The planned study duration is 36 months, with a total of 98 patients to be randomised to either standard advanced life support (ALS) or ALS plus REBOA. Adult patients with an in-hospital CA, successful placement of a femoral artery introducer sheath and any electrical cardiac activity in the initial rhythm analysis are eligible for inclusion. Exclusion criteria comprise traumatic CA, asystole as the initial rhythm, pregnancy and CA occurring on intensive care units, in the operating room or in cardiac catheter laboratory. The primary outcome is sustained return of spontaneous circulation lasting for at least 20 min. Secondary and exploratory outcomes include survival, neurological outcome, changes in aortic blood pressure, end-tidal CO ETHICS AND DISSEMINATION: The study protocol (Version 2.1, 11.02.2026) was approved by the Cantonal Ethics Committee of Cantone Bern (2025-D0108). Study results will be disseminated through peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT07434726.