Abstract

Back ground:  Post-operative nausea and vomiting is a common morbidity observed after anesthesia and surgery. It is of significance especially in the context of day care surgery. PONV is the reason for unanticipated hospital admission, resulting in stress and financial burden. In this prospective double blind study, we have compared the effectiveness of Dexamethasone and Ondansetron in the prevention of PONV.

Materials and Methods: After obtaining approval of the hospital ethical committee and informed consent, 60 adult patients of either sex, scheduled for elective ENT surgeries under general anaesthesia were included in the study. In this prospective double blind study, Group A received Ondansetron 4mg and Group B received Dexamethasone 8mg just before induction of general anesthesia. The antiemetic efficacy and side effects were analyzed. The results of the study were statistically analyzed using the student t test and chi square test.

Results: All episodes of nausea and vomiting in the first 24 hour postoperative period during the interval of 0-6 hrs (early PONV) and 6-12 hours (late PONV) were evaluated by a numeric scoring system of PONV. The entire post operative experience was assessed using an 11 point verbal numeric scoring system (0 = not at all satisfied, 10 = fully satisfied).There is no statistically significant difference between Ondansetron and Dexamethasone in preventing postoperative nausea and vomiting either in the early or late postoperative period. But clinically significant difference was noted between these two groups .ie, when 83.3% had no nausea and vomiting in the Dexamethasone group 93.3% had no nausea and vomiting in Ondansetron group. But in the late postoperative period, Dexamethasone had a better effect, ie, while 86.7% had no vomiting in Ondansetron group, 93.3% were free of vomiting episodes in Dexamethasone group. Patient satisfaction score was also comparable.

Conclusion:  In the prevention of postoperative nausea and vomiting, Ondansetron is clinically better than Dexamethasone in early postoperative period. Dexamethasone is more effective in late postoperative period. Dexamethasone being cheaper and easily available can be considered in prevention of PONV.

Keywords: PONV, Ondansetron, Dexamethasone.