Epidural analgesia with bupivacaine does not improve splanchnic tissue perfusion after aortic reconstruction surgery

Inadequate splanchnic tissue perfusion is relatively common during and afte r aortic surgery. We hypothesized that vasodilatation caused by thoracic ep idural analgesia improves splanchnic brood flow and tissue perfusion after aortic surgery. tn this prospective, randomized, controlled study, we studi ed 20 patients undergoing elective aortic-femoral or aortic-iliac reconstru ction surgery. Gastric and sigmoid colon mucosal P-CO2 and pH were measured during surgery. An epidural bolus of bupivacaine 40 mg followed by infusio n of 15 mg h(-1) was started after operation in 10 patients. After operatio n, splanchnic blood flow and gastric and sigmoid colon mucosal P-CO2 and pH were measured before and 2 h after the start of epidural analgesia. During surgery, the gastric mucosal-arterial P-CO2 difference remained stable, wh ereas the sigmoid mucosal-arterial P-CO2 difference increased during aortic clamping but returned to pre-clamping values after declamping. After opera tion, epidural analgesia had no effect on gastric or sigmoid mucosal-arteri al P-CO2 differences or on splanchnic blood flow.