Improved preservation of the rat liver for orthotopic liver transplantation: use of University of Wisconsin-lactobionate solution and retrograde reflushing.

This study investigated cold preservation and reflushing before orthotopic liver transplantation by examining (1) new University of Wisconsin solution (UW) versus Euro-Collins solution (EC), (2) retrograde reflushing (RR) versus antegrade reflushing (AR), and (3) the addition of a platelet-activating inhibitor (PAF), superoxide disumatase (SOD), or SOD + catalase to UW. Syngeneic, male Lewis rats (200 to 400 gm) were used. Preservation for 9, 12, 18, or 24 hours in UW or EC with RR (through the inferior vena cava) was used. The 9- and 12-hour groups experienced a significant decrease in the weight of the grafts preserved in UW. The 3-week survival rate after 9 hours of preservation (n = 6) in UW was 66%, and the survival rate with EC was 0% (p less than 0.025). After 12 hours of preservation, recipient survival rate was 70% (n = 10) with UW versus 0% (n = 4) with EC (p less than 0.025). RR of the graft with cold lactated Ringer's solution immediately before reimplantation significantly improved 3-week survival in the 12-hour group to the level of the control group (no preservation time, 69%). Preservation for 12 hours in UW followed by AR yielded a 3-week survival of 14%; 3-week survival for the RR group was 70% (p less than 0.025). Furthermore, RR allowed a 3-week survival of 33% and 20% after 18 and 24 hours of UW preservation, respectively. In the 24-hour RR/UW group, donor pretreatment with SRI 63-441 (20 mg/kg, intravenously) and recipient treatment with SOD (15 mg/kg, intravenously) or SOD + catalase (15 mg/kg and 5000 units/kg, intravenously) produced a 3-week survival comparable to preservation in UW followed by RR alone. These studies show that UW is a profound improvement over EC for cold preservation of liver and that the new application of RR to rat orthotopic liver transplantation improves survival. However, the addition of free-radical scavengers or PAF does not improve organ function or recipient survival in this model.