Mechanical ventilation settings during weaning from venovenous extracorporeal membrane oxygenation

Abstract

Abstract Objectives: To describe clinical characteristics, mechanical ventilation strategies, and outcomes in patients with severe acute respiratory distress syndrome (ARDS) during weaning from venovenous extracorporeal membrane oxygenation (VV ECMO). Design: Retrospective, multicenter cohort study over 7 years. Settings: Two tertiary ICUs, high-volume ECMO centers in France and Italy. Patients: Patients with ARDS on ECMO and successfully weaned from VV ECMO. Measurements and main results: Patients were classified based on their mechanical ventilation modality during the sweep gas-off trial (SGOT) with either controlled mechanical ventilation or spontaneous breathing (i.e. pressure support ventilation). The primary endpoint was the time to successful weaning from mechanical ventilation within 90 days post-ECMO weaning. Among 393 adult patients with severe ARDS successfully weaned from ECMO, 292 were on controlled ventilation, and 101 were on spontaneous breathing during SGOT. The 90-day probability of successful weaning from mechanical ventilation was not significantly different between the two groups (sHR [95%CI], 1.23[0.84-1.82]). However, spontaneous breathing during SGOT was associated with a shorter duration of mechanical ventilation and ICU length of stay after ECMO discontinuation, without an increase of ECMO-related complications, such as severe bleeding or pneumothorax, compared to controlled ventilation. After adjusting for covariates, older age, higher pre-ECMO sequential organ failure assessment score, pneumothorax, ventilator-associated pneumonia, and renal replacement therapy were independently associated with a lower probability of successful weaning from mechanical ventilation after ECMO weaning. Contrarily, mechanical ventilation modalities during SGOT did not demonstrate an independent association with the likelihood of successful weaning. Conclusions: A weaning ECMO strategy incorporating spontaneous breathing during SGOT appears safe and is associated with favorable outcomes. Further research is needed to assess the optimal ventilation strategy during weaning off VV ECMO and its impact on short- and long-term outcomes.