Dear Editor,

Extracorporeal cardiopulmonary resuscitation (ECPR) refers to the initiation of venoarterial extracorporeal membrane oxygenation (VA ECMO) during cardiac arrest to restore systemic perfusion with oxygenated blood [1]. Prolonged no-flow and low-flow times in refractory cardiac arrest lead to full-body hypoxia and pose a serious risk of reperfusion injury [2]. During ECPR, oxygenated blood is infused in the distal abdominal aorta, exposing the splanchnic circulation to hyperoxia and reperfusion stress [3]. Non-occlusive mesenteric ischemia (NOMI), as a manifestation of ischemia-reperfusion injury of the guts, is likely underdiagnosed after ECPR.

Diagnostic accuracy of laboratory parameters and computed tomography angiography (CTA) in detecting ischemia of the guts is limited in early disease stages (Online Supplement). Ischemic lesions often involve the right hemicolon and may be detectable by colonoscopy [5]. We included colonoscopy early after ECPR (i.e., within 72 h after collapse) into clinical routine assessment of all patients submitted to our intensive-care unit (ICU) after successful ECPR. The primary aim of this study was to assess the incidence of colon ischemia after ECPR. Secondary aims included the assessment of feasibility and safety.

This single-center prospective observational study was conducted between March 2023 and March 2025. Consecutive adult patients undergoing ECPR after in-hospital or out-of-hospital cardiac arrest (IHCA, OHCA) were eligible. Patients with evidence of mesenteric ischemia prior to ECPR were excluded. Colonoscopy was planned in all patients surviving > 24 h and performed at the bedside in the ICU within 72 h after collapse. The primary endpoint was endoscopic evidence of colon ischemia. Secondary endpoints included procedure-related complications, need for surgical intervention, and survival to hospital discharge.