Background

Extracorporeal membrane oxygenation (ECMO) was frequently used to treat patients with severe coronavirus disease‑2019 (COVID‑19)‑associated acute respiratory distress (ARDS) during the initial outbreak. Care of COVID‑19 patients evolved markedly during the second part of 2020. Our objective was to compare the characteris‑tics and outcomes of patients who received ECMO for severe COVID‑19 ARDS before or after July 1, 2020.

Methods

We included consecutive adults diagnosed with COVID‑19 in Paris–Sorbonne University Hospital Network ICUs, who received ECMO for severe ARDS until January 28, 2021. Characteristics and survival probabilities over time were estimated during the first and second waves. Pre‑ECMO risk factors predicting 90‑day mortality were assessed using multivariate Cox regression.

Results

Characteristics of the 88 and 71 patients admitted, respectively, before and after July 1, 2020, were compa‑rable except for older age, more frequent use of dexamethasone (18% vs. 82%), high‑flow nasal oxygenation (19% vs. 82%) and/or non‑invasive ventilation (7% vs. 37%) after July 1. Respective estimated probabilities (95% confidence intervals) of 90‑day mortality were 36% (27–47%) and 48% (37–60%) during the first and the second periods. After adjusting for confounders, probability of 90‑day mortality was significantly higher for patients treated after July 1 (HR 2.27, 95% CI 1.02–5.07). ECMO‑related complications did not differ between study periods.

Conclusions

90‑day mortality of ECMO‑supported COVID‑19–ARDS patients increased significantly after July 1, 2020, and was no longer comparable to that of non‑COVID ECMO‑treated patients. Failure of prolonged non‑invasive oxygenation strategies before intubation and increased lung damage may partly explain this outcome.