Efficacy and safety of ramosetron versus ondansetron for postoperative nausea and vomiting after general anesthesia: a meta-analysis of randomized clinical trials

BACKGROUND Postoperative nausea and vomiting is a common side effect of general anesthesia. In this study, we performed a meta-analysis on the efficacy and safety of ramosetron versus ondansetron in the prevention of postoperative nausea and vomiting using the most recently published randomized controlled clinical studies. METHODS PubMed and EMBASE were searched for randomized controlled clinical trials comparing the efficacy and safety of ramosetron and ondansetron. The meta-analysis was performed using Review Manager version 5.3 (Cochrane Collaboration, Oxford, UK). Dichotomous outcomes are presented as the relative risk (RR) with a 95% confidence interval (CI). RESULTS A total of 898 patients from nine selected studies were treated with antiemetics after surgery, including 450 patients who received ondansetron 4 mg and 448 patients who received ramosetron 0.3 mg. The meta-analysis showed no statistically significant difference between the two groups with regard to prevention of postoperative nausea (PON) during different time periods in the 48 hours after surgery. When comparing the efficacy of ramosetron and ondansetron in the prevention of postoperative vomiting (POV), at various time intervals in the 24 hours after surgery, ramosetron was significantly more efficient than ondansetron: 0-6 hours (RR 0.46, 95% CI 0.24-0.92; P=0.03), 0-24 hours (RR 0.72, 95% CI 0.52-1.00; P=0.05), and 6-24 hours (RR 0.51, 95% CI 0.31-0.84; P=0.008). At other time periods between 24 and 48 hours after surgery, ramosetron did not show better efficacy than ondansetron. When comparing the safety profiles of ramosetron and ondansetron, fewer side effects were recorded in the ramosetron group (RR 0.65, 95% CI 0.47-0.91; P=0.01). CONCLUSION Our meta-analysis demonstrates that ramosetron was more effective than ondansetron in the prevention of early POV (0-24 hours) with fewer recorded side effects. However, our study did not reveal any statistically significant differences in efficacy between ramosetron and ondansetron in the prevention of PON or late POV (at 24-48 hours).