Comparison of ramosetron with combined ramosetron and midazolam for preventing postoperative nausea and vomiting in patients at high risk following laparoscopic gynaecological surgery.

Objectives: This randomized, double-blind study compared the antiemetic efficacy of ramosetron with that of ramosetron combined with midazolam, and investigated whether the timing of midazolam administration affected the incidence of postoperative nausea and vomiting (PONV).

Methods: Nonsmoking female patients undergoing laparoscopic gynaecological surgery were randomized to three groups: group R received intravenous (i.v.) normal saline at induction of anaesthesia and 30 min before the end of surgery; group RM1 received midazolam i.v. at induction of anaesthesia and normal saline i.v. 30 min before the end of surgery; group RM2 received normal saline i.v. at induction of anaesthesia and midazolam i.v. 30 min before the end of the surgery. All patients received 0.3 mg ramosetron i.v. at the end of surgery. Incidence of PONV and need for rescue antiemetics were assessed during the 48-h postoperative period.

Results: A total of 126 patients were included in the analyses. There was no significant difference in the incidence of severe nausea, emetic episodes or use of antiemetics among the three groups. The incidence of complete response (no PONV and no rescue antiemetics) was significantly higher in the RM1 (30/41; 73%) and RM2 (30/42; 71%) groups compared with group R (19/43; 44%).

Conclusions: Midazolam given at induction of anaesthesia or at the end of the surgery, combined with ramosetron, was more effective than ramosetron alone in reducing the incidence of PONV.