[Patient-controlled analgesia with tramadol and tramadol/droperidol mixture after abdominal hysterectomy: a double-blinded, randomized controlled trial].

OBJECTIVE: To compare the clinical efficacy and side effects of tramadol and the mixture of tramadol and droperidol for postoperative patient-controlled analgesia (PCA). METHODS: Sixty female patients, aged 18 - 65, scheduled for elective abdominal total hysterectomy with inhalational general anesthesia (induced with fentanyl and propofol, maintained with O(2)-N(2)O and enflurane or isoflurane supplemented by intermittent iv fentanyl and vercuronium for muscle relaxation) were allocated into 2 groups of 30 patients in a random and double blind manner: group 1 (20 mg tramadol) and group 2 (20 mg tramadol plus 0.1 mg droperidol), both with a lockout time of 10 minutes. The VAS, analgesic doses, and side effects were observed 4, 8, 12, 20, 28, and 36 hours after operation respectively. RESULTS: Adequate analgesia was achieved with tramadol or the mixture of tramadol and droperidol. The nausea rates and vomiting rates at any time point in the group 2 were all significantly lower than those in the group 1 (all P < 0.05). Ten patients in the group 1 needed treatment of metoclopramide, and none of patients in the group 2 needed antiemetic (P < 0.01). No significant differences were observed in VAS, sedation score or vital signs (all P > 0.05). CONCLUSION: Providing a similar quality of analgesia with less nausea and vomiting as well as little need for sedative, the combination of tramadol and droperidol is superior to tramadol alone for post-operative PCA.