The Effects of Thoracic Epidural Anesthesia on Hepatic Perfusion and Oxygenation in Healthy Pigs During General Anesthesia and Surgical Stress

Perioperative liver injury due to decreased perfusion may be an underlying mechanism behind the development of systemic inflammatory response syndrome. We designed this animal study to assess whether thoracic epidural an-esthesia (TEA) impairs liver oxygenation due to induced hypotension. After ethical approval, 19 anesthetized and acutely instrumented pigs were randomly assigned to 3 groups (control and TEA alone versus TEA plus volume loading). Bupivacaine 0.5 % 0.75 mL per segment was in-jected into the epidural space, aiming for a T5 to T12 block. After baseline values were obtained, measurements were repeated 60 and 120 min after epidural injection. TEA was associated with decreased mean arterial blood pressure but no change in total hepatic blood flow. Oxygen deliv-ery to the liver and oxygen uptake remained unchanged