Pre-hospital ECPR for refractory cardiac arrest - The PRECARE pilot feasibility study.

Background: Survival from refractory out of hospital cardiac arrest (OHCA) treated with conventional cardiopulmonary resuscitation (CCPR) remains low. Extracorporeal cardiac resuscitation (ECPR) is increasingly be utilised in refractory OHCA, with outcomes influenced by the duration of cardiac arrest prior establishing ECMO flow (low flow time). Pre-hospital ECPR aims to reduce the low flow time. Pre-hospital physicians may represent a workforce who could deliver ECPR, increasing access and sustainability.

Methods: A single-arm open-label feasibility trial of pre-hospital ECPR delivered by pre-hospital physicians. Patients under the age of 70 years with a witnessed collapse, an initial shockable rhythm and within a 45-minute radius of the mobile team were eligible for pre-hospital ECPR. Once extracorporeal support flow was established, patients were transported to one of three ECMO capable centers. The primary aim was to assess the feasibility of pre-hospital ECPR in this setting.

Results: From August 2023 to June 2024, over 103 recruitment days, the pre-hospital ECPR team attended 123 confirmed cardiac arrests, 12 (10%) patients received pre-hospital ECPR equating to one case per 8 shifts. All patients were successfully cannulated on scene while the patient was in cardiac arrest. The mean time from dispatch to team arrival was 18.5 min (range 9-29); mean time from decision to ECMO flow was 17 min (range 10-34) and the mean total low flow time (arrest to ECMO flow) was 39 min (range 24-56). Four (33%) patients were successfully liberated from VA ECMO support, 3 (25%) patients survived to hospital discharge neurologically intact (CPC 1-2).

Conclusions: Pre-hospital ECPR delivery by trained pre-hospital medical teams is possible and reduces OHCA low flow times. Larger studies are required to assess efficacy and cost effectiveness.