Combination of dexamethasone and ondansetron in prophylaxis nausea and vomiting in gynecological operation.

Background: Postoperative nausea and vomiting occur in about 20-30% of women; however, some reports have estimated the rate at 70% in at-risk individuals. Gynecological and obstetrical operations are among the most frequent types of surgeries to be associated with nausea and vomiting postoperatively. Ondansetron and dexamethasone have been compared in a variety of studies for postoperative prophylaxis.

Aim of the study: This study was conducted in order to compare the efficacy and safety of dexamethasone and ondansetron, alone or in combination, for prevention of postoperative nausea and vomiting in a sample of Iraqi women undergoing gynecological surgeries.

Patients and methods: The study was conducted in Al-Diwaniyah Province, a region belonging to the Mid-Euphrates sector of Iraq, at the Child and Maternity Teaching Hospital. The study started in June 2021 and the work with the research was accomplished in September 2022. The study included a total of 100 women undergoing different gynecological surgeries such as ovarian cystectomy, oophorectomy, ectopic pregnancy, total abdominal hysterectomy, and myomectomy. All participants involved in the study were categorized randomly into four groups, namely, dexamethasone, ondansetron, combined, and placebo groups.

Results: The rates of nausea in the different groups were analyzed. The rates of nausea in dexamethasone, ondansetron, and combined groups revealed a significant decrease compared with that of placebo group (P < 0.05), and the rate was significantly lower in combined group when compared with dexamethasone and ondansetron groups (P < 0.05). The rate of nausea in combined group was significantly lower than that of dexamethasone and ondansetron groups. The rate of vomiting in combined group was significantly lower than that of placebo group and less than that of the dexamethasone group (P < 0.05).

Conclusion: Based on our study and previous reports, both dexamethasone and ondansetron are efficient and safe in preventing nausea and vomiting in gynecological operations; however, combination of both provides the best results.