RESUMO
BACKGROUND: The causes of hepatic dysfunction after exposures to the halogenated inhaled anesthetics may be free radical, metabolites of inhaled anesthetics, immune reaction and hypoxic damage by decreasing total hepatic blood flow. The present study was performed to comparison of estimated hepatic blood flow and systemic hemodynamic changes between the general anesthesia with enflurane and thoracic epidural anesthesia in rabbits. METHODS: In general anesthesia group with enflurane, anesthesia was performed with enflurane 2vol% and 100% oxygen for 60 minutes. In thoracic epidural anesthesia group, epidural block was done at T5 level with 0.4 ml/kg of 1% lidocaine. Hepatic blood flow was estimated by clearance of indocyanine green according to the constant infusion method before and 30, 60 minutes after anesthesia. Heart rate, mean arterial pressure, central venous pressure and splanchnic vascular resistance were measured at the same time in both groups. RESULTS: Heart rate was decreased significantly in thoracic epidural anesthesia group and mean arterial pressure and central venous pressure were decreased significantly in both groups at 30, 60 minutes. Hepatic blood flow was decreased at 30, 60 minutes in both groups. Splanchnic vascular resistance was increased significantly 30, 60 minutes in thoracic epidural anesthesia group. There were significant differences in mean arterial pressure and splanchnic vascular resistance between two groups. There was no difference in hepatic blood flow between two groups. CONCLUSIONS: The decreased hepatic blood flow was caused by decreased mean arterial pressure in general anesthesia group with enflurane and by increased splanchnic vascular resistance in thoracic epidural anesthesia group.