Extracorporeal membrane oxygenation in patients with COVID-19: 1-year experience

Background: Extracorporeal membrane oxygenation (ECMO) in patients with coronavirus disease 2019 (COVID-19) showed reasonable outcomes. However, recent studies indicated a negative trend and analysis is needed. Methods: Baseline characteristics, laboratory parameters, and outcomes of ECMO-supported patients with COVID-19 were analyzed in a retrospective single-center study. We included hospital admissions until February 28, 2021;patients were followed until discharge/death. Eventually, we compared data between patients hospitalized before and after September 1, 2020. Results: Median age of patients treated with ECMO (n=39) was 56 years;most patients were males (n=28, 72%). Median mechanical ventilation time (prior to ECMO) was 6 days, while the median ECMO duration was 19 days. Overall survival rate was 41%. In the sub-analysis, survival until discharge in the first and second epidemic waves was 53% (n=19) and 30% (n=20), respectively (P=0.2). At baseline, compared with patients of the first wave, those of the second wave had higher median body mass index (28.2 vs. 31.1 kg/m(2), respectively, P=0.02), bicarbonate (27 vs. 31.8 mmol/L, respectively, P=0.033), plasma free hemoglobin (36 vs. 58 mg/L, respectively, P=0.013), alanine aminotransferase (33 vs. 52 U/L, respectively, P=0.018), and pH (7.29 vs. 7.42, respectively, P=0.005), lower rate of pulmonary hypertension (32% vs. 0%, respectively, P=0.008), lower positive end-expiratory pressure (14 vs. 12 cmH(2)O, respectively, P=0.04), longer median ECMO duration (16 vs. 24.5 days, respectively, P=0.074), and more frequent major bleeding events (42% vs. 80%, respectively, P=0.022). Conclusions: ECMO-supported patients with COVID-19 had an overall survival rate of 41%. Similar to international registries, we observed less favorable outcomes during the second wave. Further research is needed to confirm this signal and find predictors for mortality.