Experimental Study on Optimal Duration of Intermittent Hepatic Vascular Clamping

Sim, Mun Sup; Kim, Hae Young; Bae, Young Tae; Kim, Dong Heon; Moon, Sang Eun; Seol, Mi Young; Son, Han Chul; Kwon, Kyung Sool

Abstract

BACKGROUND/AIMS: During partial liver resection, intermittent hepatic pedicle clamping results in less hepatocyte damage than continuous clamping. However, the optimal duration of ischemia and reperfusion during the intermittent hepatic vascular clamping has not been determined. So, this study aimed to determine the optimal duration of ischemia and reperfusion.
METHODS
Using partial ischemia(70%) rat model, the maximum limit of ischemic time and minimum limit of reperfusion time were evaluated. To assess the maximum limit of ischemic time, rats were divided into three groups for 15, 20, and 30 minutes of ischemia followed by 60 minutes reperfusion. To assess the minimum limit of reperfusion time, reperfusion following 15-minute ischemia was repeated 10 times in three groups for 5, 10, and 15 minutes of reperfusion. In the ischemic experiments, hepatic blood flow and ATP levels were serially measured. In the reperfusion experiments, serum liver enzyme, 1-month survival rates, as well as, hepatic blood flow and ATP level were serially measured and then, the 1-month survival rate was compared between the continuous ischemic group and intermittent ischemic groups.
RESULTS
(1) In the 15- minute ischemic group, the hepatic blood flow and ATP levels returned to preischemic values after 1 hour of reperfusion. But in the 20- or 30-minute ischemic groups, the hepatic blood flow and ATP levels did not return to preischemic values. (2) In the 15-minute reperfusion group, the survival rate and hepatic function, such as hepatic blood flow and ATP levels, were better than the 5- or 10-minute reperfusion groups.
CONCLUSION
In 70% partial ischemic rat model, the maximum limit of ischemic time was 15 minutes. In cases of intermittent ischemia and reperfusion, there was less liver damage in the 15-minute reperfusion group compared to the 5- or 10-minute reperfusion groups.