Low dose ondansetron with dexamethasone for prophylaxis of postoperative nausea and vomiting following laparoscopic...

Ondansetron and dexamethasone combination is effective for prophylaxis against postoperative nausea and vomiting (PONV). Ondansetron, when compared to dexamethasone, is known to cause more adverse effects and is relatively expensive. The present study evaluated the efficacy of standard dose and low dose ondansetron, i.e. 100 μg/kg and 50 μg/kg, respectively, with dexamethasone 8 mg for PONV prophylaxis in laparoscopic cholecystectomy (LC).

After the approval from the Institutional Ethics Committee-Human Research [IEC-HR] and prospective CTRI registration, this randomized, double-blind interventional study was conducted following informed consent from each participant. Patients aged 18-65 years of either sex, with ASA physical status I or II, undergoing LC under general anesthesia, were included and divided into groups C and L. Patients in groups C and L received 100 μg and 50 μg of ondansetron, respectively, in combination with 8 mg dexamethasone. The incidence of PONV in first 6 hrs, PONV score, rescue antiemetic consumption, rescue analgesia, and hemodynamic parameters were recorded.

A total of 110 patients were included with 55 in each group. Incidence of PONV in the first 6 hours was found to be higher in 1-2 hour- and 2-3-hour time intervals in group L; but was significant only at 1-2-hour time interval (P < 0.05). Proportion of patients needing rescue antiemetic in the first 6 hours was higher in group L but was not statistically significant.

We observed that 50 μg/kg combination of ondansetron was associated with higher incidence of post operative nausea in the immediate postoperative period than 100 μg/kg dose; however, no significant difference was observed in incidence of post-operative vomiting between two doses following LC.