To explore the application value of normothermic machine perfusion (NMP) for marginal liver in a porcine model.

Six healthy male Ba-Ma mini pigs (10-12 months old) were equally divided into two groups according to the experimental design: static cold storage 6 hours (SCS 6 h) followed by 2 h NMP (SCS 6 h+ NMP 2 h) group and (SCS 24 h+ NMP 2 h) group. The NMP perfusion platform was set up based on Liver Assist System, blood of donor, four-channel physiological instruments and self-made perfusion cannula integration. The perfusate of the two groups were collected at 0, 15, 60, 90 and 120 min during NMP, which were used for liver function test and arterial blood gas analysis. A little liver tissue (fixed by 10% formaldehyde) was obtained from the left lobe, which was used for HE staining.

The level of ALT and AST were higher in (SCS 24 h+ NMP 2 h) group than those of (SCS 6 h+ NMP 2 h) group at the beginning of NMP, and both rise gradually in the two groups after perfusion. The median pH and oxygen partial pressure value of (SCS 24 h+ NMP 2 h) group were 7.28 and 46 mmHg at the beginning of NMP, both higher than those in (SCS 6 h+ NMP 2 h) group (7.36, 52 mmHg), but the above indexes in (SCS 24 h+ NMP 2 h) group are progressively closer to or even better than those of (SCS 6 h+ NMP 2 h) group. Pathology results showed that liver congestion and inflammatory cell infiltration were serious in (SCS 24 h+ NMP 2 h) group before NMP, whereas after perfusion, these symptoms had improved markedly without significant difference to (SCS 6 h+ NMP 2h) group.

The NMP perfusion platform based on Liver Assist System and blood of donor could effective improve the quality of long-time cold preservation marginal livers, which means that it had important clinical and fundamental research value for marginal livers repairment and donor liver pool enlargement.