Respiratory compliance related to prognostic of lung transplant patients with veno‑venous extracorporeal membrane oxygenation support

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) plays an important role in the perioperative care of critically ill lung transplant patients. However, the factors predicting prognosis are unclear. This study assessed the association between static respiratory compliance (Crs) and outcomes of lung transplant patients receiving VV-ECMO in terms of 90-day mortality. Data were retrospectively collected for patients that underwent lung transplantation with VV-ECMO support during 2022-2023. Patients were divided into two groups according to the early postoperative Crs: lower Crs (Crs < 25 ml/cmH₂O) and higher Crs (Crs ≥ 25 ml/cmH₂O). Differences in patient characteristics and prognosis were then compared between the two groups. Receiver operating characteristic (ROC) curve analysis was used to evaluate the value of Crs for predicting 90-day mortality and univariate Cox proportional hazard model analysis was performed to estimate risk of Crs. Data were available for a total of 85 patients, including 50 (58.8%) patients in the higher Crs group and 35 (41.2%) patients in the lower Crs group. A lower Crs was significantly associated with a longer postoperative ECMO duration (hours, 42 vs. 24; P = 0.022), longer postoperative ventilator time (days, 3.7 vs. 2.0; P = 0.003), higher application of continuous renal replacement therapy (CRRT) (20.0% vs. 6.0%; P = 0.049), higher incidence of pneumonia (42.9% vs. 20.0%; P = 0.023), and higher 90-day mortality (22.9% vs. 6.0%; P = 0.023). The area under the curve of Crs for predicting 90-day mortality was 0.661 (P = 0.034). A higher Crs was a protective factor (hazard ratio = 0.925 [0.870-0.984)] P = 0.014). For lung transplant patients receiving VV-ECMO support, Crs < 25 ml/cmH₂O is associated with more complications and higher 90-day mortality. As Crs is easily obtained at the bedside, it may be useful for predicting prognosis and guiding patient management.