Real-Time Biomarkers of Liver Graft Quality in Hypothermic Oxygenated Machine Perfusion

Background: Hypothermic oxygenated machine perfusion has emerged as a strategy to alleviate ischemic-reperfusion injury in liver grafts. Nevertheless, there is limited data on the effectiveness of hypothermic liver perfusion in evaluating organ quality. This study aimed to introduce a readily accessible real-time predictive biomarker measured in machine perfusate for post-transplant liver graft function. Methods: The study evaluated perfusate analytes over a 90-day postoperative period in 26 patients randomly assigned to receive a liver graft following dual hypothermic machine perfusion in a prospective randomized controlled trial. Machine perfusion was consistently conducted end-ischemically for at least 120 min, with real-time perfusate assessment at 30-min intervals. Graft functionality was assessed using established metrics, including Early Allograft Dysfunction (EAD). Results: Perfusate lactate concentration after 120 min of machine perfusion demonstrated significant predictive value for EAD (AUC ROC: 0.841, p = 0.009). Additionally, it correlated with post-transplant peak transaminase levels and extended hospital stays. Subgroup analysis revealed significantly higher lactate accumulation in livers with post-transplant EAD. Conclusions: Liver graft quality can be effectively assessed during hypothermic machine perfusion using simple perfusate lactate measurements. The reliability and accessibility of this evaluation support its potential integration into diverse transplant centers.