Association of early positive end-expiratory pressure settings with ventilator-free days in patients with coronavirus disease 2019 acute respiratory distress syndrome: A secondary analysis of the Practice of VENTilation in COVID-19 study.
Valk CMA., Tsonas AM., Botta M., Bos LDJ., Pillay J., Serpa Neto A., Schultz MJ., Paulus F., Writing Committee for the PRoVENT-COVID∗ Collaborative Group None.
BackgroundThere is uncertainty about how much positive end-expiratory pressure (PEEP) should be used in patients with acute respiratory distress syndrome (ARDS) due to coronavirus disease 2019 (COVID-19).ObjectiveTo investigate whether a higher PEEP strategy is superior to a lower PEEP strategy regarding the number of ventilator-free days (VFDs).DesignMulticentre observational study conducted from 1 March to 1 June 2020.Setting and patientsTwenty-two ICUs in The Netherlands and 933 invasively ventilated COVID-19 ARDS patients.InterventionsPatients were categorised retrospectively as having received invasive ventilation with higher (n=259) or lower PEEP (n=674), based on the high and low PEEP/FiO2 tables of the ARDS Network, and using ventilator settings and parameters in the first hour of invasive ventilation, and every 8 h thereafter at fixed time points during the first four calendar days. We also used propensity score matching to control for observed confounding factors that might influence outcomes.Main outcomes and measuresThe primary outcome was the number of VFDs. Secondary outcomes included distant organ failures including acute kidney injury (AKI) and use of renal replacement therapy (RRT), and mortality.ResultsIn the unmatched cohort, the higher PEEP strategy had no association with the median [IQR] number of VFDs (2.0 [0.0 to 15.0] vs. 0.0 [0.0 to 16.0] days). The median (95% confidence interval) difference was 0.21 (-3.34 to 3.78) days, P = 0.905. In the matched cohort, the higher PEEP group had an association with a lower median number of VFDs (0.0 [0.0 to 14.0] vs. 6.0 [0.0 to 17.0] days) a median difference of -4.65 (-8.92 to -0.39) days, P = 0.032. The higher PEEP strategy had associations with higher incidence of AKI (in the matched cohort) and more use of RRT (in the unmatched and matched cohorts). The higher PEEP strategy had no association with mortality.ConclusionIn COVID-19 ARDS, use of higher PEEP may be associated with a lower number of VFDs, and may increase the incidence of AKI and need for RRT.Trial registrationPractice of VENTilation in COVID-19 is registered at ClinicalTrials.gov, NCT04346342.