Background: Veno-venous extra-corporeal membrane oxygenation (ECMO) cannulations are mostly performed while patients are heavily sedated and mechanically ventilated. For patients with acute respiratory distress syndrome (ARDS), cannulating for ECMO while awake and spontaneously breathing, as well as treating without sedation and mechanical ventilation, has potential advantages. This study aimed to compare clinical outcomes between patients cannulated for ECMO while awake and patients cannulated while sedated and mechanically ventilated. 

Methods: A retrospective multicenter study. Data were accessed from the Israeli ECMO registry of patients with COVID-19-induced ARDS treated at eight ECMO centers in Israel. The study group comprised 24 patients who were cannulated while awake and spontaneously breathing. A control group comprised 96 patients who were cannulated after sedation and mechanical ventilation, matched 1:4 by age, sex, and body mass index. The primary outcome was six-month survival. Secondary outcomes were: the duration of ECMO therapy, the duration of invasive mechanical ventilation-free ECMO therapy, and the duration of invasive mechanical ventilation. 

Results: The mean age was 52 + 11 years; 78% were males. Fifteen patients (63%) in the study group were eventually intubated. The mean durations on ECMO and in the intensive care unit did not differ between the groups. The study group had a higher six-month survival (75% vs. 49%, p = 0.02) and fewer infectious complications such as pneumonia or bacteremia (21% vs. 40%, p < 0.001) compared to the control group. After adjusting for PO₂/FiO₂ ratio and for the COVID-19 variant, the hazard ratio was 0.45 (C.I 0.19–1.06, p = 0.069). 

Conclusions: Awake VV-ECMO cannulation in COVID-19-induced ARDS is feasible in selected patients and was associated with higher survival in unadjusted analyses. However, after adjustment for key covariates, this association was attenuated and did not reach statistical significance.