The Impact of a Standardized Refractory Hypoxemia Protocol on Outcome of Subjects Receiving Venovenous Extracorporeal Membrane Oxygenation.

BACKGROUND Current mechanical ventilation practice and the use of treatment adjuncts in patients requiring extracorporeal membrane oxygenation (ECMO) for refractory hypoxemia (RH) vary widely and their impact on outcomes remains unclear. In 2015, we implemented a standardized approach to protocolized ventilator settings and guide the escalation of adjunct therapies in patients with RH. This study aimed to investigate ICU mortality, its associated risk factors, and mechanical ventilation practice before and after the implementation of a standardized RH guideline in patients requiring venovenous ECMO (VV-ECMO). METHODS This was a single-center, retrospective cohort study of patients undergoing VV-ECMO due to RH respiratory failure between January 2008 and March 2015 (before RH protocol implementation) and between April 2015 and October 2019 (after RH protocol implementation). RESULTS A total of 103 subjects receiving VV-ECMO for RH were analyzed. After implementation of the RH protocol, more subjects received prone positioning (6.7% vs 23.3%, P = .02), and fewer received high-frequency oscillatory ventilation than before launching the RH protocol (0% vs 13.3%, P = .01). Plateau pressure was also lower before initiation of ECMO (P = .04) and at day 1 during ECMO (P = .045). Driving pressure was consistently lower at days 1, 2, and 3 after ECMO initiation: median 13.0 (interquartile range [IQR] 10.6-18.0) vs 16.0 (IQR 14.0-20.0) cm H2O at day 1 (P = .003); 13.0 (IQR 11.0-15.9) vs 15.5 (IQR 12.0-20.0) cm H2O at day 2 (P = .03); and 12.0 (IQR 10.0-14.5) vs 15.0 (IQR 12.0-19.0) cm H2O at day 3 (P = .005). CONCLUSIONS The implementation of a standardized RH guideline improved compliance with a lung-protective ventilation strategy and utilization of the prone position and was associated with lower driving pressure during the first 3 days after ECMO initiation in subjects with refractory hypoxemia.