The outcomes of COVID-19 patients on venovenous extracorporeal membrane oxygenation (VV-ECMO) varied. We aim to investigate the variability concerning location and timeframe. We conducted a retrospective analysis of data from 351 institutions in 53 countries. The primary outcome was survival to hospital discharge or death up to 90 days from ECMO start. The associations between calendar time (month and year) of ECMO initiation and the primary outcome were examined by Cox regression modeling. Multivariable survival analyses were adjusted for the time of ECMO start, age, body mass index, APACHE II, SOFA, and the duration of mechanical ventilation before ECMO.

1060 adult COVID-19 patients enrolled in the COVID-19 Critical Care Consortium (COVID Critical) international registry and required VV-ECMO support. The study period is from January 2020 to December 2021. The median age was 51 years old, and 70% were male patients. Most patients were from Europe (39.3%) and North America (37.4%). The in-hospital mortality of the entire cohort was 47.12%. In North America and Europe, there was an increased probability of death from May 2020 through February 2021. Latin America showed a steady rate of survival until late in the study. South Asia, the Middle East, and Africa showed an increased chance of mortality around May 2020. In the Asian-Pacific region, after February 2021, there was an increased probability of death. The time of ECMO initiation and advanced patient age were associated with increased mortality.

Variability in the outcomes of COVID-19 patients on VV-ECMO existed within different regions. This variability reflects the differences in resources, policies, patient selection, management, and possibly COVID-19 virus subtypes. Our findings might help guide global response in the future by early adoption of patient selection protocols, worldwide policies, and delivery of resources.