The Current Role and Future Applications of Machine Perfusion in Liver Transplantation

Abstract

The relative paucity of donor livers suitable for transplantation has sparked innovations to preserve and recondition organs to expand the pool of transplantable organs. Currently, machine perfusion techniques have led to the improvement of the quality of marginal livers and to prolonged cold ischemia time and allowed for the prediction of graft function through analysis of the organ during perfusion, improving the rate of organ use. In the future, the implementation of organ modulation might expand the scope of machine perfusion beyond its current usage. The aim of this review was to provide an overview of the current clinical use of machine perfusion devices in liver transplantation and provide a perspective for future clinical use, including therapeutic interventions in perfused donor liver grafts.

Normothermic machine perfusion for liver transplantation: current state and future directions

“…Bicarbonate is an important component of bile secreted by cholangiocytes that line the bile canaliculi. Low bile pH, considered to be less than 7.4 in most studies, is a marker of injury to the biliary epithelium which later presents as ischemic cholangiopathy [20,[39][40][41]. Similarly, an elevated bile to perfusate glucose ratio indicates an absence of cholangiocyte glucose absorption and suggests ischemic injury to the bile ducts [38].…”

“…The same defatting cocktail with l-carinitine was utilized in a series of discarded human livers which demonstrated a 40% reduction in steatosis after 6 h of NMP [46]. Other defatting techniques, including lipid aphresis filters, reduction of insulin and glucose in the perfusate, and prolonged perfusion (> 7 days), are in the early stages of investigation [39,47,48].…”

“…The transition to performing what is a complex operation during predominantly daytime hours is likely to result in positive downstream effects including decreased rates of burnout and improved quality of life among transplant surgeons and operating room teams. In addition, it may result in elimination of cold ischemia time constraints currently present for geographically distant donors, further improving organ utilization rates [15 ▪ ,39]. The use of NMP is also likely to allow for increased flexibility managing multiple simultaneous organ offers.…”

Machine perfusion in liver transplantation: recent advances and coming challenges

“…Posttransplant outcomes are generally improving, but there remains both a critical lack of access to life-saving liver grafts, and a higher than desirable rate of serious posttransplant complications [1–3]. The demand for liver grafts is increasing, making both organ access and posttransplant outcomes of urgent international concern [4–6]. Machine perfusion is theorized to combat both issues, expanding the donor pool and providing mechanisms to prevent serious early and delayed posttransplant complications [7–13,14 ▪▪ ].…”