First Preliminary Experience with Preservation of Liver Grafts from Extended-Criteria Donors by Normothermic Machine Perfusion in Asia

Abstract

Background: Normothermic machine perfusion (NMP) can provide access to evaluate and resuscitate high-risk donor livers before transplantation. The purpose of this study was to determine the efficacy of NMP in preservation and assessment of extended-criteria donor (ECD) livers in China. Case Reports: From September 2018 to March 2019, 4 liver grafts from 3 transplant center defined as ECD were subjected to NMP, and then were transplanted successfully. During perfusion, perfusion parameters such as vascular flow, glucose level, lactate clearance, and bile production/composition were recorded to assess graft viability. All recipients were followed up 6 months after transplantation. Conclusions: NMP provides a potential tool for preservation and assessment of ECD livers in China.

Viability Assessment in Liver Transplantation—What Is the Impact of Dynamic Organ Preservation?

“…Various authors claim this technology provides “near-physiological” conditions, although the question, what circumstances from organ donation, transport and transplantation are really physiological? appears [ 9 , 10 , 74 ].…”

“…Stable perfusion flow rates during NMP were therefore suggested by many [ 22 , 59 , 60 ]. A few authors have defined more specific viability criteria with a portal vein and hepatic artery flow above >500 mL/min and >150 mL/min, respectively ( Table 2 ) [ 9 , 57 , 74 ]. Some case series described a reduction in flow rates toward the end of prolonged NMP, a sign of sinusoidal exhaustion and advanced injury [ 12 ].…”

“…Along with advanced donor liver injury or ischemia times, and subsequent tissue hypoxia and anaerobic metabolism, a low perfusate pH is usually seen during NMP. The majority of case series recommend to maintain a physiological pH range between 7.3 and 7.45 [ 19 , 20 , 74 , 80 , 81 ]. Many other factors have however impact as confounders, including the perfusate composition and additives.…”

“…Ceresa et al found 4 livers with no appropriate bile flow within 4 h of NMP, all were transplanted and showed immediate function and no relevant graft quality-related complications ( Table 2 ) [ 21 ]. The four livers, transplanted by Zhang et al after assessment during NMP showed immediate full function and would have been declined according to the Groningen criteria, because none achieved 10mL bile production within the first 2.5 h of NMP [ 74 ]. Such results are further supported by the VITTAL study, where all transplanted livers achieved hepatocyte viability criteria including bile production.…”

Research progress on hepatic machine perfusion

“…One of the main advantages of NMP is that the functional status of grafts can be evaluated by measuring liver metabolic indicators such as bile production and liver enzymes before transplantation 54 . The first case of ECD transplantation by NMP in Asia was reported recently 55 . Multicenter randomized controlled trials have shown that NMP can reduce graft injury, prolong organ preservation time and improve organ utilization 9 , 56 .…”