305: Prospective Clinical Evaluation of New Ecco2r Technology With Ulpv in Moderate Ards Patients

Introduction: This multicenter, prospective, study in France evaluated the safety and effectiveness of PRISMALUNG+ (PL+), a new ECCO2R membrane lung designed for use alone or with continuous renal replacement therapy (CRRT & PL+), as an adjunct to mechanical ventilation for treating hypercapnic acidosis during ultra-lung protective ventilation (ULPV) in moderate acute respiratory distress syndrome (ARDS) patients. Methods: From April 2021 to December 2023, 58 ARDS patients across 10 centers received heparin and had stepwise tidal volume (VT) reduction from 6 mL/kg to 4 mL/kg. Sweep gas (100% O2 at 10L/min) was initiated when PaCO2 >50 mmHg. Outcomes were measured at 8 and 24 hours; safety was monitored until discharge or day 28. Results: Data are presented as median [IQR], unless stated otherwise. Among 58 (PL+=42 patients; CRRT & PL+=16 patients), mainly male patients (74.1%), aged 63.5 [55.0-69.0] years, baseline SAPS II was 45.0 [39.0-63.0], SOFA was 8.5 [6.0-11.0], and PaO2/FiO2 was 163.3 [135.0-204.7] mmHg. Before ECCO2R, peak hypercapnia and respiratory acidosis reached PaCO2 of 53.0 [50.0-55.0] mmHg and a pH of 7.30 [7.24-7.36]. ECCO2R lasted for 43.1 [24.1-69.3] hours at 350 [300-400] mL/min flow. VT fell from 6.0 [6.0-6.1] to 4.0 [4.0-4.30] (p < 0.0001), and driving pressure improved from 12.0 [10.0-16.0] cmH2O to 10.0 [8.0-13.0] cmH2O (p=0.0001) after 24 hours. Ventilatory ratio decreased from 1.7 [1.5-2.1] at baseline to 1.3 [1.0-1.6] after 24 hours (p < 0.0001). Respiratory acidosis resolved with treatment, as evidenced by normalization of pH and reduction of PaCO2 within 24 hours. Specifically, baseline pH was 7.38 [7.31-7.43] and remaining unchanged at 24 hours (7.38 [7.34-7.42]; p = 0.2704) while baseline PaCO2 was 42.0 [39.0-46.0] mmHg compared to 45.2 [41.0-50.1] mmHg at 24 hours (p=0.0025). CO2 clearance after 8h was 82.3 mL/min (PL+) and 77.3 mL/min (CRRT & PL+). The mean (SD) lifetime of the extracorporeal circuit was 27.5 (±24.9) hours for PL+ and 46.8 (±29.0) hours for CRRT & PL+. No major bleeding events occurred during ECCO2R; however, 2 patients experienced minor ischemic strokes post-treatment, unrelated to the device. Conclusions: PL+ effectively and safely clears CO2 and enables ULPV without causing hypercapnic acidosis.