Normothermic extracorporeal perfusion of porcine and human liver following donation after cardiac death

Donation after cardiac death (DCD) has increased the pool of potential donors for liver transplantation However, DCD livers 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 transplant DCD livers. Proof-of-concept experiments using a DCD model in the pig and in a discarded DCD human liver were performed to assess the short-term (3-4 hours) feasibility, histological effects and functional efficacy of NELP. Using extracorporeal membrane oxygenation, parenteral nutrition, separate hepatic artery and portal vein perfusion, and physiological perfusion pressures, we achieved NELP and evidence of function (bile production, paracetamol removal, maintenance of normal ammonia and lactate levels) for 4 hours in the pig livers subjected to 15 and 30 minutes of cardiac arrest before explantation and for 3 hours in the human liver. There was essentially normal liver and biliary tract histology after 8 hours perfusion. Our experiments justify further investigations of the feasibility and efficacy of human DCD liver preservation by ex-vivo perfusion.