Normothermic Extracorporeal Human Liver Perfusion following Donation after Cardiac Death
Liver transplantation is a major life-saving procedure and donation after cardiac death (DCD) has increased the pool of potential liver donors. However, livers procured after DCD are at increased risk of primary graft dysfunction and biliary tract ischaemia. Normothermic extracorporeal liver perfusion (NELP) may increase the ability to protect, evaluate and, in future, transplant DCD livers. We conducted a proof-of-concept experiment using a human liver procured by DCD (deemed not suitable for liver donation) to assess the short-term (3 hours) feasibility, histological effects and functional efficacy of NELP. We used an extracorporeal membrane oxygenation circuit with separate hepatic artery and portal vein perfusion to achieve physiological perfusion pressures, and coupled this with parenteral nutrition and an insulin infusion. We achieved NELP with evidence of liver function (bile production, paracetamol removal and control of ammonia, bilirubin and lactate levels) for 3 hours. There was essentially normal liver and biliary tract histology after 8 hours of perfusion. Our experiment justifies further investigation of the feasibility and efficacy of human DCD liver preservation by NELP.