[Effect of different methods for postoperative pain management on catecholamine response to abdominal surgery]

To observe the effect of different analgesic methods and the influence of catecholamine response to elective abdominal surgery.

42 ASA I-II patients undergoing elective abdominal surgery were randomly divided into five groups. After receiving combined general and epidural anesthesia, postoperative patient-controlled epidural analgesia was provided in group RF, BF, BM with 1.2 g.L-1 ropivacaine + 2 mg.L-1 fentanyl, 1.2 g.L-1 bupivacaine + 2 mg.L-1 fentanyl, 1.2 g.L-1 bupivacaine + 80 mg.L-1 morphine respectively. Group EM received general-epidural anesthesia and patient-controlled intravenous analgesia with 0.5 g.L-1 morphine. Levels of analgesics (VAS, VRS), plasma concentrations of adrenaline and noradenaline were measured.

Effective analgesia could be achieved in all groups. VAS in groups BM and M was significantly less than that in groups RF, and VRS in groups BM was higher than that in groups RF, EM and M. There were more side effects in groups BM, M and EM, and the incidence of nausea was highest in group M(5 cases). The adrenaline concentrations in group BM one hour postoperation was lower than that in group BF, and noradrenaline in group EM was lower than that in group RF. The 24-hour postoperative values of the adrenaline and noradrenaline in group M were higher than their preoperative values.

Postoperative patient-controlled epidural or intravenous analgesia could provide effective analgesia. Epidural anesthesia during operation or epidural analgesia postoperation could depress stress responses, thus it is a more effective analgesic method.