Development and Assessment of Normothermic Machine Perfusion Preservation for Extracorporeal Splitting of Pig Liver.

BACKGROUND Studies have shown that normothermic machine perfusion (NMP) exerts a significant protective role for donations after cardiac death (DCD) livers and verified the effects of NMP in preservation, repair, and preoperative assessment of human donor livers. The objective of this study was to verify the effectiveness and stability of NMP system by splitting pig livers in perfusion preservation. MATERIAL AND METHODS Four healthy Ba-Ma miniature pigs were used. The livers were harvested, and then connected to the NMP system to split the livers. The indexes during the splitting were recorded, the serological indices were measured, and routine pathological examination of liver tissue were observed. RESULTS With splitting, the portal vein pressure and the hepatic artery pressure were not significantly changed. The flow in the portal vein and hepatic artery reduced respectively from 455±107.55 mmHg, 180.75±59.46 mmHg before splitting to 392.5±125.27 mmHg and 126.25±6.99 mmHg after splitting. The liver preservation temperature was controlled to 38.83±0.24 to 38.93±0.43°C during splitting. At the beginning of perfusion preservation, the alanine aminotransferase(ALT), lactate dehydrogenase(LDH), and alkaline phosphatase (ALP) were lower than the baseline level; ALT and LDH gradually increased with splitting, whereas ALP was maintained in a lower level in the splitting. At the beginning of perfusion preservation, aspartate aminotransferase(AST) was comparable with the baseline value, and it was gradually increased with splitting. The cell structure in the liver before NMP preservation and after splitting did not show significant changes. CONCLUSIONS The NMP device developed in this study can be used for donor liver preservation and splitting, without causing significant liver damage.