A55-42 High Mechanical Power on Extracorporeal Membrane Oxygenation: Implications for Mortality and Post-transplant Recovery in Double Lung Transplant

Rationale Primary graft dysfunction (PGD) is a cause of early morbidity and mortality after double lung transplantation (DLTx) and shares pathophysiologic features with ventilator-induced lung injury (VILI). Mechanical power (MP) quantifies the energy delivered from the ventilator to the lungs per unit time, integrates several determinants of VILI and is linked to adverse outcomes in critical illness and postoperative respiratory failure. A threshold of ≥ 17 J/min is commonly used to define high MP, based on prior studies in acute respiratory distress syndrome (ARDS). Perioperative extracorporeal membrane oxygenation (ECMO) is employed in DLTx to facilitate ultra-protective ventilation and minimize MP exposure. This study investigates whether higher postoperative MP is associated with PGD, mortality, and discharge disposition in ECMO-supported DLTx recipients. Methods We conducted a retrospective analysis of 52 DLTx recipients managed with perioperative ECMO. High MP was defined as ≥ 17 J/min. ECMO utilization patterns included pre-transplant only (11, 21.2%), pre-transplant and continued from the operating room (7, 13.5%), initiated intraoperatively and continued postoperatively (8, 15.4%), postoperative only (11, 21.2%), and ≥2 runs or conversion between VV/VA modes (15, 28.8%). Most patients were supported with VV ECMO (39, 75.0%), followed by VA ECMO (11, 21.2%) and Protek/RVAD (2, 3.8%). Outcomes included PGD, mortality, and discharge disposition (home, rehabilitation/skilled nursing facility, expired). MP and driving pressures were recorded at 1, 25, 49, and 73 hours post-transplant. Associations between categorical variables and outcomes were assessed using chi-square or Fisher’s exact tests, and logistic regression evaluated relationships between high MP, mortality, and PGD. Results Among 52 patients, 37 (71%) developed PGD. High MP was not associated with PGD, though driving pressure at 49 hours showed a trend toward increased odds (OR 1.62, 95% CI 0.92-2.85, p = 0.09). In contrast, high MP at 49 hours was significantly associated with mortality (OR 6.48, 95% CI 1.06-39.56, p = 0.043). Discharge disposition differed between high and low MP groups (Fisher’s exact p = 0.03), with patients with high MP less likely to be discharged home and more likely to require rehabilitation or expire. Conclusions In DLTx recipients supported with perioperative ECMO, high MP at 49 hours was associated with increased mortality and worse discharge disposition, though not PGD. The early postoperative period may represent a critical window to optimize ventilator settings and minimize mechanical stress. These findings highlight the potential role of MP monitoring as a bedside physiologic target to guide ventilatory management and improve post-transplant recovery. This abstract is funded by: None