Protective effects of lidocaine injected into the hepatoduodenal ligament on warm ischemia-reperfusion injury to the rat liver

BACKGROUND: Ischemia-reperfusion (IR) injury to the liver is still a critical and daunting problem in the field of hepatobiliary surgery. Ischemic preconditioning (IP) of the liver serves as an effective approach against IR injury. This study was to develop a novel procedure that could mimic IP, but might be more feasible than IP during surgery. METHODS: Eighty-two SD rats were randomly divided into 5 groups. L group (n = 21): 0.4% lidocaine (10 mg/kg) was injected into the hepatoduodenal ligament 10 minutes before a 40-minute hepatic IR. IP group (n = 16): a 5-minute ischemia was followed by a 10-minute reperfusion prior to a 40-minute hepatic IR. ILR group (n = 15): after a 40-minute ischemia of the liver, 0.4% lidocaine (10 mg/kg) was injected into the hepatoduodenal ligament 10 minutes prior to a 40-minute reperfusion of the liver. IR group (n = 15): the liver of the rat was subjected to a 40-minute IR. Control group (n = 15): 0.9% sodium chloride was injected into the hepatoduodenal ligament without other treatments. The levels of plasma alanine transaminase (ALT) and aspartate transaminase (AST) were determined for each group after treatment. RESULTS: The mean concentrations of ALT and AST were (379.80 +/- 141.69) U/L and (606.05 +/- 220.26) U/L for the L group, (334.64 +/- 141.94) U/L and (625.68 +/- 267.06) U/L for the IP group, (523.36 +/- 170.35) U/L and (765.47 +/- 238.45) U/L for the ILP group, (524.29 +/- 163.59) U/L and (764.63 +/- 246.79) U/L for the IR group, and (150.90 +/- 27.05) U/L and (298.15 +/- 47.68) U/L for the control group (standard error of the mean). CONCLUSION: A significant decrease in ALT and AST levels was observed in the L and IP groups when compared to the ILR and IR groups (P < 0.05), but no significant difference in ALT and AST levels was observed in the L group when compared to the IP group (P > 0.05). These results suggest that pretreatment with lidocaine injected into the hepatoduodenal ligament prior to IR provides effective protection against subsequent IR injury to the liver. The novel approach of blocking innervation with lidocaine mimics hepatic IP, but is more convenient than IP at the time of liver surgery.