The Protective Effect of Prone Positioning on Human Rejected Donor Lungs during Cellular Ex Vivo Lung Perfusion

Abstract

Purpose We previously reported that prone positioning (PP) of porcine lungs during cellular ex vivo lung perfusion (EVLP) diminished inflammatory injury and improved oxygenation and other pulmonary parameters during cellular EVLP. We hypothesized that prone positioning of human lungs during cellular EVLP may diminish injury and improve function, as well. The aim of this study is to validate the previous results with porcine lungs and evaluate the potential benefits of PP EVLP with human rejected donor lungs. Methods Eleven human rejected donor lungs were flushed and stored for 15-16 hours with Perfadex. Lungs were then subjected to 2 hours of cellular EVLP with either maintenance of prone positioning (prone group, n = 6) or supine positioning (control group, n = 5). Lung function was evaluated using blood gas analysis, airway and vascular parameters, visual findings, wet/dry (W/D) ratio and lung weight at 2 hours of EVLP. Results Lung weight (LW) ratio (LW at 2 hours of EVLP/ LW prior to EVLP) was lower in Prone group than in Control group [median (interquartile range)] [1.09 (0.82-1.32) vs. 1.22 (1.01-1.50), p = 0.5] (not statistical significant). The PaO2/FiO2 (P/F) ratio of left atrial blood was significantly higher in Prone group than in Control [335.5 (297.2-392.5) vs. 198.0 (190.5-271.0) mmHg, p Conclusion These results demonstrate that PP during 2 hours of cellular EVLP result in less lung weight gain, and better P/F ratio, especially in the lower lobes. These results were consistent with our previous animal study, and suggest that prone positioning EVLP of rejected human donor lungs also may diminish IRI during EVLP.