Ex Vivo Liver Machine Perfusion Reduces the Length of Hospital Stay in Recipients of Allografts from Elderly Donors: A Systematic Review

Liver transplantation is the only curative treatment option for end-stage liver disease. As the population ages worldwide, utilization of grafts from elderly donors has the potential to expand the donor pool. Unfortunately, these allografts are associated with increased rates of primary non-function and early allograft dysfunction. Ex vivo machine perfusion (MP) may be a promising technique to overcome these challenges. A systematic review of PubMed, Web of Science, and ClinicalTrials.gov is presented for trials comparing MP to static cold storage for elderly human allografts (>= 70 years) (PROSPERO ID352930). Six clinical trials (n = 1189 patients) are included. Hypothermic oxygenated perfusion (HOPE) is used in five trials and normothermic MP (NMP) in one trial. There is limited evidence that machine perfusion has the potential to mitigate the risks associated with older livers and shorten the length of hospital stay after transplantation. There is no evidence to support superiority of one perfusion type or differences in patient and graft survival. Risk of bias is high, and level of evidence is limited regarding MP of allografts form elderly donors. Nevertheless, MP is associated with length of hospital stay. Further research is warranted to analyze MP for allografts of older age.