Preoperative versus intraoperative antiemetic strategies in patients undergoing laparoscopic cholecystectomy

Previous studies have determined ondansetron's efficacy in preventing and treating postoperative nausea and vomiting (PONV). However, evidence regarding the timing of drug administration in relation to the surgical procedure remains vague.To compare the preoperative and intraoperative administration of ondansetron on the incidence of PONV.Single-centred, randomised, double-blind trial. Patients were recruited between November 2018 and April 2021. Follow-up for PONV and retching was up to 24 h.Aretaieio University Hospital, Greece.A total of 121 patients undergoing elective laparoscopic cholecystectomy gave written consent.Patients were randomly allocated to the preoperative or the intraoperative group. The preoperative group received 4 mg of ondansetron dissolved in 100 ml of 0.9% saline 1 hour before induction of anaesthesia and 100 ml of 0.9% saline 30 min before end of surgery. The intraoperative group received 100 ml of 0.9% saline 1 h before induction of anaesthesia and 4 mg of ondansetron dissolved in 100 ml of 0.9% saline 30 min before end of surgery.The primary outcome was the incidence of nausea and/or vomiting combined at 24 h.No difference was found between the two groups regarding either the incidence of nausea and vomiting at 24 h (1.7% for the preoperative group versus 5.3% for the intraoperative group, P = 0.31) or the incidence of nausea, vomiting and retching combined (5.3% for the preoperative group versus 10.5% for the intraoperative group, P = 0.30). There was no difference between the groups in the pain intensity at rest or with coughing in the post anaesthesia care unit, at 4, 8 and 24 h postoperatively ( P = 0.961, 0.929, 0.748 and 0.883 at rest, and 0.974, 0.220, 0.235 and 0.317 with coughing, respectively).Under the current study design, we found no difference in the incidence of PONV between the administration of ondansetron 1 h before induction of anaesthesia and the intraoperative administration of ondansetron 30 min before the end of surgery.ClinicalTrials.gov NCT03023306.