Dexamethasone plus ondansetron for prevention of postoperative nausea and vomiting in patients undergoing laparoscopic cholecystectomy: A comparison with dexamethasone alone

Objective: To compare the efficacy of combination of dexamethasone plus ondansetron with dexamethasone alone for postoperative nausea and vomiting in patients undergoing laparoscopic cholecystectomy. Study Design: Double blinded randomized controlled clinical trial. Place and Duration of Study: Department of Anaesthesiology, Surgical Intensive Care Unit and Pain Management, Dow University of Health Sciences and Civil Hospital, Karachi, from March 2007 to September 2007. Patients and Methods: One hundred patients, both male and female, age 20 to 50 years, ASA Physical status I and II, scheduled for elective laparoscopic cholecystectomy under general anaesthesia were randomly allocated to two groups. Group A received dexamethasone (2 ml) plus ondansetron 4 mg (2 ml) prepared in two different syringes, and group B received dexamethasone 8 mg (2 ml) and normal saline (2 ml), prepared in two separate syringes just before induction of anaesthesia. Anaesthesia was standardized. For the first 24 hours after anaesthesia, the presence or absence of nausea and vomiting (by simply yes or no) was assessed by anaesthetist blinded to randomization. The rescue antiemetic (metoclopromide 10 mg) i.v., was given, if patient remained nauseous for more than 15 minutes, or experience retching or vomiting during study period. Results: In comparison to dexamethasone group, the frequency of nausea and vomiting was clinically and statistically lower in dexamethasone - ondansetron group (p=0.035). Use of rescue antiemetic was significantly higher in dexamethasone group (p=0.022). Two patients in group A and one patient in group B experienced peri-anal itching at time of giving dexamethasone, none of our patients experienced headache, flushing or other side effects. Conclusion: Combination of dexamethasone plus ondansetron is more effective in preventing postoperative nausea and vomiting than dexamethasone alone when used for prophylaxis of PONV before the induction of anaesthesia in patients undergoing laparoscopic cholecystectomy.