Injection dexamethasone in preventing postoperative nausea and vomiting: a comparison with placebo in the patients...

To determine the efficacy of intravenous dexamethasone for preventing postoperative nausea and vomiting (PONV) in patients undergoing laparoscopic cholecystectomy (lap-chole) and comparing it with normal saline (placebo).

Single blinded, randomized, placebo controlled, interventional study.

This study was conducted in the department of Anaesthesiology of Civil Hospital, Karachi and Dow University of Health Sciences, Karachi, from June 2005 to April 2006.

After the approval of the hospital's ethical committee, the study was conducted on 60 patients who were randomly divided into two groups, each group containing 30 patients. All belonged to A.S.A-I and A.S.A-II. Randomization was done by envelope draw method. Injections dexamethasone (8 mg in 2mls) and normal saline ( 2 mls ) were given intravenously to respective groups just before induction of anesthesia. Fisher's exact test was applied to compare proportion of PONV between two groups for the recovery room data, while Chi-square test was applied to compare the proportion of PONV between two groups during first 12 hours and second 12 hours. The p-value was calculated at the level of significance chosen as 0.05.

In the recovery room where the patient stayed for one hour 10% of patients in the dexamethasone group in comparison with 33% of the patients in the placebo group experienced PONV (p=0.028). In the ward, during first 12 hours observation period, 27% of the patients in the dexamethasone group in comparison with 43% of the patients in the placebo group experienced PONV (p=0.176). During the second 12 hours observation period, 30% of the patients in the dexamethasone in comparison with 80% of the patients in the placebo group experienced PONV (p < 0.001).

In this study, the frequency of postoperative nausea and vomiting (PONV) in the dexamethasone administered group was significantly less as compared to placebo group. As the former is freely available, economical and the single dose is not associated with any significant side effects, it should, therefore, be used more frequently in the patients undergoing lap-chole.