Machine Perfusion Across Marginal Liver Grafts: Benefits and Challenges.

Area of Science:

• Hepatology
• Transplantation Surgery
• Organ Preservation

Background:

• End-stage liver disease necessitates liver transplantation, but organ shortages lead to graft discard.
• Marginal donor grafts (elderly, steatotic, DCD) face higher discard rates.
• Machine perfusion (MP) offers a solution to expand the usable donor pool.

Purpose of the Study:

• To review evidence for hypothermic (HMP), normothermic (NMP), and normothermic regional perfusion (NRP) in marginal liver grafts.
• To assess MP's impact on graft utilization and patient outcomes.
• To identify barriers and future directions for MP adoption.

Main Methods:

• Narrative review of current evidence on HMP, NMP, and NRP.
• Analysis of MP application in elderly donors, steatotic grafts, DCD donors, and split liver transplantation.
• Examination of MP's role in ex situ therapies and extended preservation.

Main Results:

• MP significantly increases utilization of steatotic grafts (up to eightfold).
• HMP reduces biliary strictures and early allograft dysfunction.
• NMP aids viability assessment and reduces post-reperfusion syndrome; NRP benefits DCD organs.
• MP enables split liver transplantation and shows potential for antiviral therapy.

Conclusions:

• Machine perfusion modalities effectively increase the utilization of marginal donor liver grafts.
• MP improves outcomes, reduces complications, and expands the donor pool.
• Widespread adoption is limited by cost, logistics, and lack of standardized protocols; further multicenter studies are needed.