Impact of Prone Positioning after Lung Transplantation - A Single Center Experience

PURPOSE: Prone positioning has become a standard therapy in acute respiratory distress syndrome with improved oxygenation and decreased mortality. The aim of this study was to evaluate the potential benefit of prone positioning after lung transplantation (LTx) in patients with impaired gas exchange in the early postoperative period. METHODS: We retrospectively analyzed LTx recipients transplanted between 01/2014 and 12/2019 (n=553). Demographics and clinical data of these patients were collected. A subgroup analysis was performed for patients who were placed in prone position on prolonged extracorporeal membrane oxygenation (ECMO). RESULTS: During the study period 155 (28%) patients were placed in prone position immediately after LTx for a median of 19 (15-26) hours. Patients requiring prone positioning were mainly suffering from idiopathic pulmonary fibrosis (IPF) with a mean age of 44.3 (±1.4) years. Before prone position, median PO(2)/FiO(2) (P/F ratio) was 179 (120-280) mmHg and median dynamic lung compliance (C(dyn)) was 24.1 (18.3-30.6) ml/cmH(2)O. Both parameters significantly increased after proning - median P/F ratio increased to 353 (255-414; p<0.0001) mmHg and median C(dyn) to 28.3 (21.3-35.2; p=0.008) ml/cmH(2)O. 41 patients were placed in prone position while being supported by postoperatively prolonged femoro-femoral veno-arterial (VA) ECMO). No complications related to prone positioning (such as kinking of ECMO lines, dislocation of ECMO cannulas) were reported. Further, in this subgroup, P/F ratio (148 (81.3-219.3) mmHg to 317 (153.9-403.3) mmHg; p= 0.0002) and C(dyn) (16.6 (12.2-26.4) ml/cmH(2)O to 21.8 (14.6-29.8) ml/cmH(2)O; p=0.05) improved significantly by proning. Nevertheless, length of mechanical ventilation, length of intensive care unit (ICU) and hospital stay were significantly longer with a median of 2 (1.8-9.3), 12 (7-29) and 35 (21-53) days in the proning group compared to 1.4 (0.9-2.8), 7 (4-13) and 25 (18-37) days in the non-proning group (all p<0001). CONCLUSION: Prone positioning significantly improved oxygenation in LTx recipients with a complex immediate postoperative course. Placing a patient with prolonged ECMO support in prone positioning is feasible and safe.