Postoperative nausea and vomiting (PONV) is a common complication in patients undergoing general anesthesia. It is reported that PONV is observed in 50% of patients 24 hours after general anesthesia and upto 80% in high risk patients. The patients experiencing PONV may experience severe discomfort that it is important to prevent PONV. There are several prophylactic agents for PONV. 5-HT3 receptor antagonist is the most commonly used agent and other agents such as corticosteroid, NK1 receptor antagonist can also be used. Previous studies have reported the efficacy of benzodiazepine(midazolam) in a low targeting dose as a prophylactic agent of PONV. The efficacy of low dose remimazolam (short acting benzodiazepine) on PONV has not been evaluated.~According to Fourth consensus guideline for the management of postoperative nausea and vomiting (2020), three prophylactic anti-emetics are recommended for patients with three or more of the risk factors of PONV. As the patients included in our study have three or more of risk factors of PONV (women, postoperative use of opioid, nonsmokers), three prophylactic anti-emetics are recommended. Our center has routinely been using 5-HT3 receptor antagonist (ramosetron) and corticosteroid (dexamethasone) for women undergoing laparoscopic cholecystectomy. However, we still find many patients complaining nausea and vomiting after operation. Therefore, we are willing to investigate the low supplemental dose of remimazolam on the prophylaxis of PONV.
The present trial is to study the effect of low dose remimazolam on postoperative nausea and vomiting (PONV) in patients at risks of PONV (women, postoperative use of opioid, nonsmokers) undergoing laparoscopic cholecystectomy.