The Effects of Topical Cooling in Ischemia-Reperfusion Injury of Rabbit Liver

Choi, Jin Goo; Shin, Young Do; Lee, Sang Mok; Koh, Suck Hwan; Hong, Sung Wha; Yoon, Choong

Abstract

BACKGROUND: Major hepatic surgery often requires temporary occlusion of the portal triad in order to minimize intraoperative bleeding. The Occlusion of portal triad may induce hepatic ischemia-reperfusion injury. Hepatic hypothermia is intended to suppress hepatic metabolism by lowering the liver temperature, to reduce oxygen consumption, and to minimize ischemic damage to the liver. This study was undertaken to evaluate the effects of topical cooling following ischemia on the liver.
METHODS
Twenty-four New Zealand white rabbits were divided into three groups; group A (n=8) received no clamping, group B (n=8) received only clamping, and group C(n=8) received topical cooling using ice slush during clamping. In group B and C, duration of ischemia was 30 miniutes and duration of reperfusion was 60 minutes. Serum alanine aminotransferase(ALT) and purine nucleoside phophorylase(PNP) were measured immediately before clamping, after 30-minute clamping, and after 60-minute reperfusion. Hepatic tissue adenosine triphosphate(ATP), xanthine oxidase, and malondialdehyde( MDA) plus 4-hydroxyalcenals(4HA) were measured after reperfusion.
RESULTS
Group C was topically cooled and reached the lowest level of 23.3 degrees C after 20 minutes of cooling. The results showed that ALT levels were significantly lower in group C than in group B(p<0.01), but PNP levels showed no significant differences between them. ATP levels showed no significant differences among the three groups. Xanthine oxidase and MDA plus 4HA levels were significantly lower in group C than in group B(P<0.01).
CONCLUSION
These results suggest that topical cooling has a protective effect on parenchymal cells by reduction of oxygen free radicals produced by xanthine oxidase.