Effects of thoracic epidural anesthesia on survival and microcirculation in severe acute pancreatitis: a randomized experimental trial

Introduction: Severe acute pancreatitis is still a potentially life threatening disease with high mortality. The aim of this study was to evaluate the therapeutic effect of thoracic epidural anaesthesia (TEA) on survival, microcirculation, tissue oxygenation and histopathologic damage in an experimental animal model of severe acute pancreatitis in a prospective animal study. Methods: In this study, 34 pigs were randomly assigned into 2 treatment groups. After severe acute pancreatitis was induced by intraductal injection of glycodesoxycholic acid in Group 1 (n = 17) bupivacaine (0.5%; bolus injection 2 ml, continuous infusion 4 ml/h) was applied via TEA. In Group 2 (n = 17) no TEA was applied. During a period of 6 hours after induction, tissue oxygen tension (tpO(2)) in the pancreas and pancreatic microcirculation was assessed. Thereafter animals were observed for 7 days followed by sacrification and histopathologic examination. Results: Survival rate after 7 days was 82% in Group 1 (TEA) versus 29% in Group 2: (Control) (P < 0.05). Group 1 (TEA) also showed a significantly superior microcirculation (1,608 +/- 374 AU versus 1,121 +/- 510 AU; P < 0.05) and tissue oxygenation (215 +/- 64 mmHg versus 138 +/- 90 mmHG; P < 0.05) as compared to Group 2 (Control). Consecutively, tissue damage in Group 1 was reduced in the histopathologic scoring (5.5 (3 to 8) versus 8 (5.5 to 10); P < 0.05). Conclusions: TEA led to improved survival, enhanced microcirculatory perfusion and tissue oxygenation and resulted in less histopathologic tissue-damage in an experimental animal model of severe acute pancreatitis.