TIMING OF ARTERIALIZATION IN LIVER-TRANSPLANTATION

Objective This study analyzed the pathophysiologic sequela of differen t modes of graft reperfusion in liver transplantation. Summary Backgro und Data The grafted liver may be reperfused either immediately after completion of portal anastomosis followed by delayed arterial reconstr uction or simultaneously by portal and arterial blood ii all vascular anastomoses are completed during the anhepatic period. Methods Delayed arterialization, that is, arterial reperfusion 8 minutes after portal revascularization (n = 12), was compared with simultaneous arterializ ation (n = 8) using the model of syngeneic orthotopic liver transplant ation in male Lewis rats. After cold storage for 24 hours in Universit y of Wisconsin (UW) solution, intravital fluorescence microscopy was e mployed 30 to 90 minutes after reperfusion to assess hepatic microvasc ular perfusion, leukocyte accumulation, and phagocytic activity of Kup ffer cells. Results Compared with delayed arterialization, the number of both nonperfused acini and nonperfused sinusoids was reduced after simultaneous reperfusion by 71% (p = 0.008) and 78% (p < 0.001), respe ctively. Leukocyte accumulation in sinusoids and postsinusoidal venule s after simultaneous arterialization decreased by 17% (p = 0.01) and 6 4% (p < 0.001), respectively. In addition, simultaneous revascularizat ion was able to attenuate Kupffer cell activation, indicated by signif icantly slower adherence of latex beads injected 80 minutes after repe rfusion. Improved hepatocellular excretory function after simultaneous arterialization was demonstrated by increased bile flow during the ob servation period of 90 minutes after reperfusion (2.24 +/- 0.7 vs. 0.9 5 +/- 0.4 mL/100 g liver [mean +/- SEM], p < 0.05). Conclusions Timing of arterial reperfusion in liver transplantation may be of critical i mportance in the prevention of Various manifestations of reperfusion i njury.