Effect of prophylactic dexamethasone on nausea and vomiting after laparoscopic gynecological operation : meta -analysis

Sex of female and laraproscopic surgery are both risk factors related to postoperative nausea and vomiting, and dexamethasone is used as anti-emetic in some operations. A meta-analysis of randomized trials was performed to determine the effect of prophylactic dexamethasone administration on postoperative nausea and vomiting, pain and complications in patients undergoing laparoscopic gynecological operation. Methods: A systematic literature search was conducted to identify all randomized clinical trials. The primary outcome was the incidence and severity of postoperative nausea and vomiting. The secondary outcomes include postoperative pain and complications. Results: Totally 1801 patients were enrolled in 11 eligible randomized trials comparing effect of prophylactic dexamethasone administration on postoperative nausea and vomiting with placebo. The pooled incidence of nausea, vomiting, nausea and vomiting, and rescue anti-emetic was significantly lower in dexamethasone group than placebo group during post-anesthesia care unit (10.5% vs 18.2%, OR 0.51, 95% CI 0.31-0.84; 6.5% vs 17.1%, OR 0.31, 95% CI 0.17-0.56; 17.0% vs 35.4%, OR 0.33, 95% CI 0.21-0.50; 6.7% vs 23.3%, OR 0.22, 95% CI 0.10-0.49, p 0.00001) and within the first postoperative 24 hours (25.2% vs 40.3%, OR 0.46, 95% CI 0.32-0.66; 14.4% vs 36.6%, OR 0.27, 95% CI 0.19-0.40; 33.0% vs 69.0%, OR 0.18, 95% CI 0.13-0.26; 21.0% vs51.1%, OR 0.26, 95% CI 0.16-0.41, P 0.00001). No significant difference was found about theincidence of rescue analgesia between dexamethasone group and placebo group (48.5% vs 56.4%,OR 0.68, 95% CI 0.40-1.18, P=0.17). Conclusion: Prophylactic dexamethasone administration decreases the incidence of nausea and vomiting after laparoscopic gynecological operations during post-anesthesia care unit and within the first postoperative 24 hours. (286 words) Postoperative nausea and vomiting are the most common complications after anesthesia and surgery, and both sex of female and type of laparoscopic operation are risk factors1. It is certain of a remarkably high incidence after laparoscopic gynecological surgery, which is reported as nearly 70% within the first postoperative 24 hours2. It is very important to find an effective treatment to alleviate postoperative nausea and vomiting. Dexamethasone was first used as an antiemetic in patients receiving chemotherapy for cancer treatment by a central mechanism involving endogenous prostaglandin and opioid production3,4. And then some trials showed that dexamethasone alone or combination with traditional anti-emetics may decrease the incidence and severity of postoperative nausea and vomiting5,6. Furthermore, perioperative dexamethasone administration may decrease postoperative pain by modulationg the systemic physiologic response in favor of antiinflammatory mediators. Researchers have reviewed the pathophysiologic effects and clinical implications of perioperative dexamethasone administration, but the variability in surgical procedures has precluded definitive conclusions regarding the effectiveness of dexamethasone5. The present meta-analysis was conducted to determine the effect of prophylactic dexamethasone administration on postoperative nausea and vomiting, pain, and complications after laparoscopic gynecological operation.