[Effectiveness of clonidine and fentanyl addition to bupivacaine in postoperative patient controlled epidural analgesia].

Background And Objectives: The aim of this prospective randomized double-blinded study was to compare the analgesic and side-effects of bupivacaine in combination with clonidine or fentanyl during patient-controlled-epidural analgesia (PCEA) in the postoperative period after abdominal hysterectomy.

Methods: 75 patients from 18 to 65 years of age with ASA status I - II were investigated. After preoperative epidural catheterization, the patients were operated in general anesthesia. After surgery, the patients were randomly allocated to 3 PCEA-groups: Group B 0.125 % bupivacaine, Group F 0.125 % bupivacaine plus 1 microg x ml (-1) fentanyl, Group C 0.125 % bupivacaine plus 0.75 microg x ml (-1) clonidine (10 ml loading dose, 5 ml repetitive bolus dose, 10 min lockout time, 30 ml limit within 4 h). During the following 24 hours, hemodynamic parameters, pain score using visual analog scale (VAS), total analgesic consumption, additional analgesic requirements, sedation, satisfaction, nausea scores and probable side-effects were evaluated.

Results: Total analgesic consumption was not different between Group F and Group C, but lower than in Group B (p < 0.05). Additional analgesic use was not different between the groups. Group F and Group C had lower VAS-scores in 24 hours than Group B (p < 0.05). Hemodynamic and sedation scores of patients were not different. In Group C, incidence of nausea was lower and satisfaction of patients was higher (p < 0.05).

Conclusions: Addition of clonidine or fentanyl to local anesthetics for PCEA can reduce the analgetic demand. Epidural clonidine can reduce postoperative nausea and is connected with higher patients' satisfaction.