Twelve patients undergoing gastrectomy received combined epidural and splanchnic nerve blockade (Group E&S), and changes in plasma ACTH, cortisol, glucose and FFA were compared with those undergoing gastrectomy under general anaesthesia (Group G) or epidural analgesia alone (Group E). Plasma ACTH increased in all groups on the day of operation and was significantly higher in Group G than the other groups. Levels of ACTH in Group E&S were lower than Group E, but the differences were not significant. Cortisol response in Group G was most pronounced and prolonged. This cortisol response was significantly attenuated in Group E and was further inhibited in Group E&S. Blood glucose and FFA increased in Groups G and E during the operation but the increase was significantly less in Group E. In Group E&S, glucose and FFA concentrations showed practically no change throughout the study, being significantly lower than in Group E. The results indicated that the splanchnic nerve is responsible for producing endocrine-metabolic responses to gastric surgery even under epidural blockade.