Objectives: 

Establishing an effective “chain of survival” for out-of-hospital cardiac arrest (OHCA) requires addressing gender disparities, which have been reported in both prehospital and in-hospital treatments. However, evidence of gender disparity in extracorporeal cardiopulmonary resuscitation (ECPR), which might contribute to differences in outcomes between sexes, remains limited. We aimed to investigate gender disparities in the administration of ECPR for OHCA.

Design: 

A secondary analysis of a prospective nationwide database.

Setting: 

The Japanese Association for Acute Medicine Out-of-Hospital Cardiac Arrest (JAAM-OHCA) Registry, a multicenter database from 164 hospitals with emergency departments in Japan, collected data between June 2014 and December 2022.

Patients: 

Adult patients (≥ 18 yr) with OHCA from nonexternal causes who did not achieve return of spontaneous circulation before or upon hospital arrival and were transported to facilities with 24-hour ECPR availability within 60 minutes of emergency call.

Interventions: 

None.

Measurements and Main Results: 

The primary outcome was receiving ECPR, defined as emergent venoarterial extracorporeal membrane oxygenation implementation before return of spontaneous circulation within 60 minutes after hospital arrival. Multilevel logistic regression analysis was used to estimate the probability of receiving ECPR, adjusting for center-level and patient-level variables. Among 47,965 eligible patients, 28,754 (60.0%) were male and 19,211 (40.0%) were female. The median age was 78.0 years. ECPR was performed in 1713 male patients (6.0%) compared with 344 female patients (1.8%). After adjusting for potential confounders, male sex was associated with significantly higher odds of receiving ECPR (odds ratio, 1.68; 95% CI, 1.46–1.93). This male predominance was consistent across most subgroups but was not observed in patients with unequivocally eligible or ineligible for ECPR.

Conclusions: 

ECPR was significantly more frequently performed in male patients with OHCA. Subgroup analyses suggest that gender disparity is particularly evident in cases where indications for ECPR are not clearly defined. Further research is needed to explore the underlying causes of this disparity.