Six-Month Survival After Extracorporeal Membrane Oxygenation for Severe COVID-19

Abstract

Objectives: The authors evaluated the outcome of adult patients with coronavirus disease 2019 (COVID-19)-related acute respiratory distress syndrome (ARDS) requiring the use of extracorporeal membrane oxygenation (ECMO).

Design: Multicenter retrospective, observational study.

Setting: Ten tertiary referral university and community hospitals.

Participants: Patients with confirmed severe COVID-19-related ARDS.

Interventions: Venovenous or venoarterial ECMO.

Measurements and main results: One hundred thirty-two patients (mean age 51.1 ± 9.7 years, female 17.4%) were treated with ECMO for confirmed severe COVID-19-related ARDS. Before ECMO, the mean Sequential Organ Failure Assessment score was 10.1 ± 4.4, mean pH was 7.23 ± 0.09, and mean PaO₂/fraction of inspired oxygen ratio was 77 ± 50 mmHg. Venovenous ECMO was adopted in 122 patients (92.4%) and venoarterial ECMO in ten patients (7.6%) (mean duration, 14.6 ± 11.0 days). Sixty-three (47.7%) patients died on ECMO and 70 (53.0%) during the index hospitalization. Six-month all-cause mortality was 53.0%. Advanced age (per year, hazard ratio [HR] 1.026, 95% CI 1.000-1-052) and low arterial pH (per unit, HR 0.006, 95% CI 0.000-0.083) before ECMO were the only baseline variables associated with increased risk of six-month mortality.

Conclusions: The present findings suggested that about half of adult patients with severe COVID-19-related ARDS can be managed successfully with ECMO with sustained results at six months. Decreased arterial pH before ECMO was associated significantly with early mortality. Therefore, the authors hypothesized that initiation of ECMO therapy before severe metabolic derangements subset may improve survival rates significantly in these patients. These results should be viewed in the light of a strict patient selection policy and may not be replicated in patients with advanced age or multiple comorbidities.

Clinical trial registration: identifier, NCT04383678.

Keywords: ARDS; COVID-19; ECLS; ECMO; acute respiratory distress syndrome; coronavirus disease 2019; extracorporeal membrane oxygenation.

Fig 1

Kaplan-Meier estimate of six-month all-cause mortality in patients treated with extracorporeal membrane oxygenation for severe COVID-19. COVID-19, coronavirus disease 2019.

Fig 2

Classification and regression tree analysis of risk factors predicting six-month all-cause mortality in patients treated with extracorporeal membrane oxygenation for severe COVID-19. COVID-19, coronavirus disease 2019; ECMO, extracorporeal membrane oxygenation.