The association of mechanical versus manual chest compressions with neurological outcomes at hospital discharge among out-of-hospital cardiac arrests treated with intra-arrest transport.

Mechanical chest compression (MCC) devices provide an opportunity to deliver high quality chest compressions during times when manual chest compressions may be challenging. Among non-traumatic out-of-hospital cardiac arrests (OHCA) treated with intra-arrest transport (IAT), we investigated the association of MCC, versus manual chest compressions, and patient outcomes. Utilizing the British Columbia Cardiac Arrest Registry, we included adult OHCA cases (January 2019 - June 2025) who were transported to hospital with ongoing chest compressions. We classified patients as MCC or manual chest compressions. We fit an adjusted logistic regression model to estimate the association of MCC (versus manual chest compressions), and favorable neurological outcome at hospital discharge (Cerebral Performance Category 1-2). During the study period, there were 1967 cases treated with IAT, of whom 243 (12%) and 1724 (84%) received MCC and manual chest compressions, respectively. Patient and cardiac arrest characteristics between groups were similar, including presence of bystander CPR and any period of on-scene return of spontaneous circulation (ROSC). Comparing MCC and manual chest compression groups: 43 (18%) and 412 (24%) had ROSC at hospital arrival, 17 (7.0%) and 135 (7.8%) survived to hospital discharge, and 16 (6.6%) and 123 (7.1%) had favorable neurological outcomes, respectively. Our logistic regression model did not detect an association of MCC (versus manual chest compressions) with favorable neurological outcome at hospital discharge with (AOR 0.93, 95% CI 0.51-1.69). Among cases treated with IAT, we did not detect an association between MCC, compared to manual chest compressions, and favorable neurological outcome at hospital discharge.