Comparison of the effects of epidural bupivacaine on hepatic injury in a rat model of ischemia and reperfusion

Gastrointestinal perfusion plays an important role in high-risk surgical procedures as the splanchnic hypoperfusion may cause endotoxemia, increase in mucosal permability an deven organ failure. Reperfusion may even cause more damage than the short period of ischemia. Hepatic ischemia reperfusion injury may be observed after extensive or radical hepatobiliary surgery. Lethal hepatocytes injury or postoperative liver dysfunction occur due to reperfusion observed after ischemia. Although the exact mechanism of the effects on splanchnic blood flow is obscure, TEA may be protective against splanchnic hypoperfusion. Nevertheless the choice of local anesthetic agent should also be taken in to consideration for these effects.Eighteen rats were randomly divided into 3 groups: Group K (n=6)=Sham (laparotomy), Group S (n=6)=Control (laparotomy, İR epidural catheter, 20 mcg/kg/h% 0,9 NaCl) and Group B (n=6)=Bupivacaine (Laparotomy, İR epidural catheter, 20 mcg/kg/h bupivacaine). Liver tissue was harvested for MDA analysis, apoptosis and histopathological examination after 60 minutes of ischemia followed by 360 minutes of reperfusion. Blood samples were also collected for TNF-?, IL-1ß, AST and ALT analysis.The AST and ALT levels were higher in ischemia and reperfusion group which took only normal saline for TAE than the sham group which was not subjected to ischemia reperfusion. In ischemia reperfusion group which took bupivacaine for TEA, IL-1 levels were significantly higher than both the group which normal saline was given for TEA and sham group. TNF-? levels were higher in ischemia reperfusion groups which took both bupivacaine and normal saline for TEA than the sham group. Besides, bupivacaine administration for TEA revealed apoptosis in all animals.These results showed that epidural bupivacaine is not a suitable agent for preventing inflammatory response and lipid peroxidation. Moreover epidural bupivacaine trigger apoptosis in hepatocytes. Further studies are needed as the literature review revealed no studies on the effects of epidural bupivacaine on hepatic ischemia reperfusion injuryKey Words: Hepatic Ischemia Reperfusion, Thoracic Epidural, Bupivacaine