Normothermic Perfusion is Superior to Subnormothermic Perfusion in a Juvenile Porcine Transplantation Model of Ex-Situ Lung Perfusion

Abstract

<h3>Purpose</h3> Ex-situ lung perfusion (ESLP) is used for the preservation, reconditioning, and treatment of marginal quality donor lungs to increase the donor pool. The ideal perfusion temperature has not been tested systematically in large animal models of ESLP. We report our results of prolonged normothermic vs subnormothermic ESLP with transplantation in a juvenile porcine model. <h3>Methods</h3> Twelve pig lungs underwent 12 hours of negative pressure ventilation (NPV)-ESLP with normothermic (38 Celsius, n=6) or subnormothermic (32 Celsius, n=6) perfusion temperatures. Three left lungs from each group were subsequently transplanted and assessed in-vivo over a four-hour period. Graft function was assessed via physiologic parameters, edema formation, cytokine profiles, and histopathologic analysis. <h3>Results</h3> Normothermic and subnormothermic lungs demonstrated stable and acceptable oxygenation during 12-hours of NPV-ESLP. While on ESLP, normothermic lungs demonstrated an improvement in compliance whereas subnormothermic lungs did not. Edema formation post-ESLP was significantly worse in the experimental group. Isolated left lung oxygenation 4 hours post-transplant was worse in the experimental group and trended towards significance. Left lung edema formation was not significantly different between groups post-transplant. Cytokine and histopathologic analysis are ongoing. <h3>Conclusion</h3> Normothermic perfusion of porcine lungs results in superior graft function compared to subnormothermic perfusion over 12-hours of NPV-ESLP and during acute in-vivo transplantation assessment.