Purpose: We assessed feasibility and safety of extracorporeal carbon dioxide removal (ECCO2R) to facilitate ultra-protective ventilation (VT 4 mL/kg and PPLAT ≤ 25 cmH2O) in patients with moderate acute respiratory distress syndrome (ARDS).
Methods: Prospective multicenter international phase 2 study. Primary endpoint was the proportion of patients achieving ultra-protective ventilation with PaCO2 not increasing more than 20% from baseline, and arterial pH > 7.30. Severe adverse events (SAE) and ECCO2R-related adverse events (ECCO2R-AE) were reported to an independent data and safety monitoring board. We used lower CO2 extraction and higher CO2 extraction devices (membrane lung cross-sectional area 0.59 vs. 1.30 m2; flow 300-500 mL/min vs. 800-1000 mL/min, respectively).
Results: Ninety-five patients were enrolled. The proportion of patients who achieved ultra-protective settings by 8 h and 24 h was 78% (74 out of 95 patients; 95% confidence interval 68-89%) and 82% (78 out of 95 patients; 95% confidence interval 76-88%), respectively. ECCO2R was maintained for 5 [3-8] days. Six SAEs were reported; two of them were attributed to ECCO2R (brain hemorrhage and pneumothorax). ECCO2R-AEs were reported in 39% of the patients. A total of 69 patients (73%) were alive at day 28. Fifty-nine patients (62%) were alive at hospital discharge.
Conclusions: Use of ECCO2R to facilitate ultra-protective ventilation was feasible. A randomized clinical trial is required to assess the overall benefits and harms. CLINICALTRIALS.GOV: NCT02282657.
Keywords: Acute respiratory distress syndrome; Extracorporeal carbon dioxide removal; Mechanical ventilation; Ventilator-induced lung injury.