Dual acellular subnormothermic machine perfusion for enhanced uterus preservation in a swine model

INTRODUCTION: Machine perfusion has rapidly developed in the last decade and demonstrated improved preservation of conventional and marginal organs by reducing ischemia and hypoxia injuries. The aim of this study was to assess whether subnormothermic machine perfusion improves graft preservation compared with SCS in a porcine uterus model. MATERIAL AND METHODS: Swine uteri were procured from circulatory-dead donors and allocated into two groups. In the experimental group, the organs were preserved with 4 h-dual subnormothermic machine perfusion (n = 4) while the control group (n = 4) underwent 4 h-static cold storage. After preservation, all uteri received ex vivo whole blood normothermic reperfusion (NMP) to simulate transplantation. Perfusate samples were analyzed from uterine arteries and veins every 30 min for gas and metabolic analysis, and weight variations were recorded continuously during perfusion. Following simulated transplantation, uterine contraction was assessed after oxytocin injection, and macrovascular perfusion was evaluated using contrast angiography. Several biopsies were procured from different parts of the uterus for histological and immunohistochemistry analysis. RESULTS: In the experimental group, the weight of the uteri and lactate difference between vein and artery decreased during subnormothermic machine perfusion. Weight gain was significantly higher in the control group (p = 0.03), which was consistent with interstitial edema observed on histological sections in this group. Uterine contraction evaluated through semi-quantitative scoring was higher in the experimental group (p = 0.02). CONCLUSIONS: In this porcine model, subnormothermic machine perfusion reduces edema and preserves contractility more effectively than static cold storage. We demonstrate its particular interest in recovering organs procured from deceased donors. In addition, subnormothermic machine perfusion may enable other applications, including graft assessment, treatment and tolerance induction.