Intravital studies on beneficial effects of warm Ringer's lactate rinse in liver transplantation.

Abstract

This quantitative in vivo fluorescence microscopy study investigated the impact of warm versus cold Ringer's lactate (RL) graft rinse on various microvascular manifestations of ischemia-reperfusion injury after liver transplantation in the rat. Syngeneic orthotopic liver transplantation, including arterial revascularization, was performed in male Lewis rats following 24 h of cold storage in University of Wisconsin (UW) solution. In one group (n = 8) liver grafts were rinsed with 4 degrees C (cold) RL, whereas in the other group (n = 8) grafts were rinsed with 37 degrees C (warm) RL immediately prior to revascularization. Hepatic microvascular perfusion, leukocyteendothelium interaction, and Kupffer cell activation were quantified 30-90 min after graft reperfusion by direct visualization with intravital fluorescence microscopy. Moreover, biliary excretory graft function was analyzed by determination of bile flow and bile salt excretion during the first 90 min after reperfusion. Compared to grafts rinsed with cold RL, acinar and sinusoidal perfusion were found to be significantly increased after rinsing the grafts with warm RL. The amount of nonperfused acini declined from 18.1% +/- 4.0% to 7.4% +/- 1.6% (P < 0.05), and the total percentage of perfused sinusoids increased from 80.1 +/- 1.4 to 88.4 +/- 1.2 (P < 0.001) after cold and warm rinse, respectively. After rinsing the graft with warm RL, WBC adherence in sinusoids and especially in postsinusoidal venules decreased significantly by 28% (P < 0.001) and 33% (P < 0.001), respectively. Kupffer cell activation was markedly reduced after rinsing with RL at 37 degrees C, as indicated by a decelerated adherence of latex particles injected 80 min after reperfusion. Excretory graft function was dramatically increased following warm RL rinse during the 90-min observation period. Bile flow was enhanced from 1.04 +/- 0.5 to 3.9 +/- 0.8 ml/100 g liver per 90 min (P < 0.01), with a parallel rise in bile salt excretion from 24.3 +/- 5.8 to 128.0 +/- 19.8 mmol/ 100 g liver per 90 min (P < 0.05) when compared to cold RL. These data strongly suggest that rinsing liver grafts with warm RL prior to reperfusion represents a simple and inexpensive way to reduce the incidence of primary graft failure secondary to ischemia and reperfusion injury in liver transplantation.