Objective: To evaluate the tolerance limit of rats to normothermic hepatic inflow occlusion under portal blood bypass.
Methods: A new rat model of normothermic hepatic inflow occlusion under portal blood bypass was established by clamping temporarily the pedicles of all liver lobes while the caudal lobe was kept as a passage of the portal blood flow. After hepatic blood flow restored, the caudal lobe was cut off. On the 7th postoperative day, survival rate, hepatic morphological changes, and the severity and reversibility of the injured energy metabolism of the liver were investigated.
Results: All rats that had been subjected to 30, 60 and 90 minutes of hepatic inflow occlusion under portal blood bypass survived on the 7th postoperative day. ischemia-reperfusion injury of the liver was reversible and compensatory in rats with hepatic inflow occlusion within 90 minutes. However, the survival rates of rats with 100, 110 and 120 minutes of hepatic inflow occlusion were 50%, 30% and 20% respectively. Liver injury of rats with 120 minutes of hepatic inflow occlusion was severe and Irreversible.
Conclusions: The tolerance limit of rats to normothermic hepatic inflow occlusion is enhanced significantly under portal blood bypass and the upper limit is 90 minutes.