Increased incidence of retching and vomiting during periovulatory phase after middle ear surgery

Purpose: To assess the effect of the menstrual cycle on postoperative retching and vomiting (R&V) after middle ear surgery, and the efficacy of prophylaxis against R&V in female patients with transdermal scopolamine during either general or local anaesthesia and with intravenous ondansetron during general anaesthesia. Method: A post hoc analysis of the data on 85 female patients with normal menstrual cycle from three prospective studies on the prophylaxis of postoperative nausea and vomiting after middle ear surgery on 205 patients. Results: Periovulatory period (menstrual dates 11-24) and history of motion sickness were predictors for R&V. During 2-24 hr, both the percentage of patients needing droperidol and the mean number of doses were lower in the perimenstrual group (menstrual dates 25-10) than in the periovulatory group 27 vs 51% (P < 0.05) and 0.2 vs 0.7 (P < 0.01), respectively. Prophylaxis with transdermal scopolamine was a predictor for lowered R&V (P < 0.05) and resulted in fewer doses of droperidol (0.4 +/- 0.7 vs 1.4 +/- 1.5, P < 0.01). This reduction was significant during the periovulatory period (from 1.4 +/- 1.3 to 0.3 +/- 0.5, P < 0.005). Ondansetron reduced the mean need for droperidol from 1.4 +/- 1.5 to 0.6 +/- 0.8, (P < 0.05). Conclusion: The incidence of R&V after middle ear surgery was lower during the perimenstrual phase. In the periovulatory phase, transdermal scopolamine was more efficient as prophylaxis against R&V than ondansetron. All female patients scheduled for middle ear surgery should be considered individually to receive prophylaxis against R&V.