Postoperative hepatic blood flow and its relation to systemic circulation and blood gases during splanchnic blockade and fentanyl analgesia.

Thirty-four patients with gallbladder disease, but otherwise healthy, were studied in connection with cholecystectomy. For postoperative analgesia, 22 patients were given a posterior splanchnic blockade with 0.5% plain lidocaine, and 12 were injected intramuscularly with fentanyl in a dose of 3.5 mug/kg b.w. Postoperatively, before administration of the analgesic agent, the cardiac output, mean arterial blood pressure, heart work and estimated hepatic blood flow were increased and the total peripheral resistance, splanchnic vascular resistance, arterial oxygen tension and base excess values were decreased. Fentanyl, in addition to its analgesic effect, also decreased the arterial oxygen tension and pH and increased the arterial carbon dioxide tension. There was little change in cardiac output, mean arterial blood pressure and estimated hepatic blood flow. Following splanchnic blockade, on the other hand, pain relief was accompanied by a decrease in cardiac output, mean arterial blood pressure and heart work to about the preoperative level, while the estimated hepatic blood flow remained unchanged and the splanchnic vascular resistance decreased rapidly. Neither total peripheral resistance nor blood gases altered as a result of splanchnic blockade.