Comparison between cellular and acellular perfusates for ex vivo lung perfusion in a porcine model

Abstract

Ex vivo lung perfusion with acellular solutions is an established technique for assessing marginal donor lungs. We evaluated the utility of a blood-based lung preservation fluid as an alternative perfusate. Donor lungs from 50-kg donation after cardiac death pigs (n = 24) were randomized into 3 groups: acellular, commercial blood-based, and Papworth-Blood. Physiologic function was evaluated using conventional markers of pulmonary vascular resistance, pulmonary compliance, lactate excretion, partial pressure of oxygen/fraction of inspired oxygen, and wet-to-dry ratios. The immunologic profile was assessed by fluorescence-activated cell sorting analysis of bronchoalveolar lavage and cells entrapped in the leucocyte filter. Cytokines were quantified using a commercial platform. No significant difference was noted in pulmonary vascular resistance (p = 0.26), compliance (p = 0.12), partial pressure of oxygen/fraction of inspired oxygen (p = 0.06) and wet-to-dry ratios (p = 0.26) between groups. There was no difference between the percentages of lymphocytes (p = 0.51), macrophages (p = 0.87), monocytes (p = 0.68), and dendritic cells (p = 0.65) in the leukocyte filters. Interleukin (IL)-1β (p = 0.36), IL-6 (p = 0.08), IL-8 (p = 0.64), and IL-18 (p = 0.14) were elevated in all groups. In bronchoalveolar lavage, IL-8 was significantly higher in the acellular group (p = 0.04). Electron microscopy cell characteristics were similar among the groups. This study demonstrated no significant difference in the physiologic, immunologic, or ultrastructural parameters between lungs perfused with cellular or acellular solutions. The Papworth-Blood solution is a potential alternative perfusate for ex vivo lung perfusion.