Abstract: AIM: To compare the clinical effects of dexmedetomidine or midazolam given in patient-controlled intravenous analgesic fentanyl solution in gynecological laparoscopic surgery.METHODS: 150 patients undergoing gynecological laparoscopic surgery, received propofol-fentanyl-rocuronium anesthesia induction and conventional sevoflurane for maintain anesthesia, were randomly assigned into five groups with 30 cases each. A dose of 16 mg ondansetron was added to PCA in group O, 5 mg midazolam was added to PCA in group M, 16 mg ondansetron and 5 mg midazolam were added to PCA in group OM, 200 μg dexmedetomidine was added to PCA in group D, while 16 mg ondansetron and 200 μg dexmedetomidine was added to PCA in group OD. PCA using 20 μg/mL of fentanyl was started in all groups postoperatively. Total volume of PCA was 60 mL, and was programmed to deliver 1 mL/h of continuous doses and a 0.5 mL bolus on demand, with a 15 minutes lockout interval. The incidence of postoperative nausea and vomiting (PONV), sedation score, visual analog scale (VAS) for pain, cumulative fentanyl dose, PCA effective pressing times and rescue drug dose for PONV or pain were investigated at the postanesthesia care unit (PACU), 6 h and 24 h after operation.RESULTS: The incidence of PONV was significantly higher in group O at three time periods than those in other four groups(P<0.05), but the sedation score was significantly lower at 6 h and 24 h postoperation than in other four groups(P<0.05). The incidence of PONV was significantly lower in group D and OD at three time periods than in group M(P<0.05). 24 cases (80%) used antiemetics in group O and was significantly more than other four groups(P<0.05). The frequency of used antiemetic in group D and OD were significantly less than other three groups(P<0.05). There were no significant difference of VAS scale at three time periods in five groups, cumulative fentanyl dose and PCA effective pressing times were significantly less in group D and OD than other three groups(P<0.05).CONCLUSION: Dexmedetomidine or midazolam given in PCA fentanyl solution proved more effective than ondansetron in preventing PONV but with some sedation. Dexmedetomidine given auxiliary analgesic and antiemetic effects was better.

Key words: Dexmedetomidine, Midazolam, Ondansetron, Patient controlled analgesia, Fentanyl