Efficacy of intraoperative low-dose remimazolam as a third antiemetic agent for preventing early postoperative nausea in high-risk patient: A Randomized controlled trial.

backgroundPostoperative nausea and vomiting (PONV) is one of the most common and distressing side effects of general anesthesia. According to the Fourth Consensus Guidelines for the Management of Postoperative Nausea and Vomiting, patients at high risk of PONV should be given at least three prophylactic antiemetic agents. As previous studies have reported antiemetic effects of sub-hypnotic doses of midazolam, a benzodiazepine, we investigated the efficacy of remimazolam, an ultra-short-acting benzodiazepine, as a third prophylactic antiemetic agent when administered at a low target dose.

methodsHundred and eight patients were randomly allocated to either remimazolm group (group R) or control group (group C). Sevoflurane was used to maintain anesthesia and the group R additionally received remimazolam (0.3 mg/kg/hr). All patients received ramosetron 0.3 mg and dexamethasone 5 mg. The incidence of PONV, quality of recovery score, and pain score at postoperative 24 h were evaluated.

resultThe groups did not have significantly different incidences and severities of PONV at postoperative 24 h. However, the group C had a statistically significantly higher incidence of nausea than the group R at postoperative 6 h (52.9% vs. 31.5%, P = 0.026). The group C had a statistically significantly higher incidence of dizziness than the group R in the post anesthesia care unit (19.6% vs. 1.9%, P = 0.008).

conclusionLow-dose remimazolam infusion did not reduce the incidence of PONV at postoperative 24 h. It was associated with a lower incidence of nausea at postoperative 6 h and dizziness in the PACU.

trial registrationClinicaltrials.gov. NCT05439057 on June 27, 2022 (retrospectively registered).