BACKGROUND
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.
OBJECTIVE
To compare the preoperative and intraoperative administration of ondansetron on the incidence of PONV.
DESIGN
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.
SETTING
Aretaieio University Hospital, Greece.
PATIENTS
A total of 121 patients undergoing elective laparoscopic cholecystectomy gave written consent.
INTERVENTIONS
Patients were randomly allocated to the preoperative or the intraoperative group. The preoperative group received 4 μ 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 μ of ondansetron dissolved in 100 ml of 0.9% saline 30 min before end of surgery.
MAIN OUTCOME MEASURES
The primary outcome was the incidence of nausea and/or vomiting combined at 24 h.
RESULTS
No difference was found between the two groups regarding either the incidence of nausea and/or vomiting at 24 h (1.7% for the preoperative group versus 5.3% for the intraoperative group, P = 0.308) or the incidence of nausea, vomiting and retching combined (5.3% for the preoperative group versus 10.5% for the intraoperative group, P = 0.297). 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).
CONCLUSION
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.
TRIAL REGISTRATION
ClinicalTrials.gov NCT03023306