Best temperature for static liver graft storage is 1°C.

Background: The best storage temperature in liver transplantation remains an unsolved question.

Methods: After storage for 24h in University of Wisconsin solution at +4°C, +1°C, or -0.5°C, rat livers were subjected, or not, to 15min of warm ischemia, rinsed with Ringer lactate, and subsequently reperfused with oxygenated Krebs-Henseleit buffer.

Results: In the presence of warm ischemia, for livers stored at +4°C, creatine kinase (CK) peaked at 21±5IUg(-1)h(-1), hepatic resistance at 34,700±1500dynscm(-5), bile flow reached 18±4μLg(-1)h(-1) after 10min, and oxygen consumption stabilized at about 25μmolg(-1)h(-1) after 20min. When livers were stored at +1°C, CK and hepatic resistance were lowered, bile production was 33±6μLg(-1)h(-1) (P<0.05 versus +4°C), and oxygen consumption was 105±10μmolg(-1)h(-1) (P<0.001). For livers stored at-0.5°C, results were not statistically different from those of the +1°C group except for bile flow, which was significantly lower. Without warm ischemia, the peak of CK (P=0.015) and the peak hepatic resistance (P<0.001) of the +4°C group were significantly increased compared with the +1°C or -0.5°C groups. However, no difference in bile flow or oxygen consumption was observed. The number of trypan blue-positive nonparenchymal cells (P=0.003) and the gain in liver weight during the reperfusion (P=0.015) were minimal after storage at +1°C.

Conclusions: Static storage at +1°C improved liver function compared with +4°C or -0.5°C. Main beneficial effect was observed with parameters reflecting sinusoidal cells injury.