Abstract 4137248: Mechanical chest compression increases intrathoracic bleeding complication in patients receiving extracorporeal cardiopulmonary resuscitation

Background: Mechanical cardiopulmonary resuscitation (CPR) is widely used to ensure high-quality CPR while reducing the burden on the medical team; however, it carries the risk of intrathoracic bleeding complications. Extracorporeal cardiopulmonary resuscitation (ECPR) for refractory cardiac arrest also poses significant challenges due to major bleeding complications. To date, no studies have specifically investigated bleeding complications when mechanical CPR is combined with ECPR. Aim: To compare the risk of major intrathoracic bleeding between manual and mechanical CPR in ECPR patients. Methods: We retrospectively analyzed 85 patients (mean age 59.6 ± 13.3 years, 90.6% male) who underwent ECPR at our hospital between April 2017 and March 2024 after failure to achieve a return of spontaneous circulation for more than 15 minutes despite appropriate CPR. From April 2020 to June 2023, our emergency department actively used mechanical CPR devices. Patients were divided into manual and mechanical CPR groups. The primary outcome was major intrathoracic bleeding requiring transcatheter arterial embolization (TAE), and the association between mechanical CPR and the outcome was examined. Results: There were 40 patients in the manual CPR group and 45 in the mechanical CPR group. Age, sex, medical history, acute coronary syndrome, out-of-hospital cardiac arrest, presence of bystander CPR, initial rhythm, total cardiac arrest time, and CPR time did not differ between the two groups. Only BSA showed a significant difference (1.75 ± 0.17 vs 1.84 ± 0.17m 2 , p = 0.018). The primary outcome occurred in 1 case (2.5%) in the manual CPR group and 9 cases (20%) in the mechanical CPR group. Univariate analysis using Firth's penalized logistic regression showed that age, thoracic transverse diameter, and mechanical CPR were significantly associated with the primary outcome. After multivariate adjustment, the associations between the primary outcome and age (HR 1.09 [1.02-1.20], p = 0.013), mechanical CPR (HR 6.62 [1.25-68.60], p = 0.024), and the outcome remained significant. Conclusions: In ECPR patients, mechanical CPR is significantly associated with an increased risk of major intrathoracic bleeding requiring TAE compared to manual CPR.