Physiological and clinical effects of two ultraprotective ventilation strategies in patients with veno-venous extracorporeal membrane oxygenation: the ECMOVENT study
Abstract
Purpose
The optimal ventilation strategy in acute respiratory distress syndrome (ARDS) patients with veno-venous extracorporeal membrane oxygenation (VV-ECMO) remains unknown. We aimed to compare the effects of two ultra-protective ventilatory strategies applied to patients with ARDS and VV-ECMO.
Methods
Our study was an observational, retrospective, single-center study with a before-and-after design. All consecutive patients treated with VV-ECMO for severe ARDS between 2016 and 2023 were included. Before 2021, patients received a quasi-apneic ventilation strategy in assist-controlled volume mode with a tidal volume (VT) of 1 ml.kg−1 predicted body weight (PBW), a respiratory rate (RR) of 5 min−1 and a PEEP set to keep plateau pressure (PPLAT) between 20 and 25 cmH2O. From 2021 onwards, the protocolized ventilatory strategy consisted in pressure-controlled mode with a PEEP of 14 cmH2O, a driving pressure (∆P) of 8 cmH2O and a RR of 10 min−1. We evaluated the impact of strategies on longitudinal respiratory mechanics and on the time to successful ECMO weaning at day-90 after VV-ECMO canulation.
Results
121 patients were enrolled, with 69 receiving the VT1 strategy, and 52 the ∆P8 strategy. Over the first 7 days of ECMO, the ∆P8 strategy was associated with significantly higher ∆P and RR, lower PaCO2, and higher static elastic mechanical power, compared with the VT1 strategy. The day-90 survival rate was 30% with the VT1 strategy, and 42% with the ∆P8 strategy (P = 0.19). Time to successful VV-ECMO weaning was 7 [4–13] days in day-90 survivors, with no significant difference between groups. The adjusted subdistribution hazard ratio associated with the ∆P8 strategy was 0.99 (95% confidence interval: 0.53–1.84), as compared to the VT1 strategy (P > 0.9).
Conclusions
In the context of our center, a ventilatory strategy targeting a PEEP of 14 cmH2O, a ∆P of 8 cmH2O and a RR of 10 min−1 led to the application of ∆P, RR and static elastic mechanical power and improved decarboxylation, compared to a strategy in volumetric mode with a VT of 1 ml.kg−1 PBW and a RR of 5 min−1, in patients with ARDS and VV-ECMO. No significant difference on clinical outcomes was observed between both strategies.