Minimum Effective dose of Dexamethasone in Combination with Midazolam as Prophylaxis against Postoperative Nausea and...

Postoperative nausea and vomiting (PONV) affects 20% and 30% of patients. As many as 60%-80% patients at high risk may be affected. Dexamethasone (D) and midazolam (M) are well studied as antiemetic. Use of D can be associated with certain undesirable side effects so minimum dose is preferred. M is a routinely used premedicant. Hence, this study was designed with both D and M in high risk patients for PONV to find minimum effective dose of D.

To determine the minimum dose of D that combined with M would provide effective prophylaxis of PONV after laparoscopic cholecystectomy (LC) in patients at high risk for PONV.

This is a prospective, randomized double-blind trial.

One hundred and fifty-five patients scheduled for elective LC were randomized to 5 groups of 31 each. Group C was given normal saline, and the rest were administered D 1 mg (group MD1), 2 mg (group MD2), 4 mg (group MD4), or 8 mg (group MD8) in combination with 0.04 mg/kg M at induction. The incidence of nausea, vomiting, severity of nausea, and the use of rescue antiemetic and postoperative pain was analyzed.

Chi-square test was used to compare incidence of study variables. Independent Student's t-test was used for continuous variables. Demographic data were compared using ANOVA. P < 0.05 was considered statistically significant.

The incidence of nausea was significantly lower in group MD4 (29%) and MD8 (6%) compared to placebo group (71%) (P < 0.001) and of vomiting was significantly lower in groups of MD2 (58%), MD4 (48%), and MD8 (6%) compared with placebo (90%) (P < 0.001) at 24 h. There was significant reduction in nausea, pain severity, and incidence of use of rescue antiemetic in MD4 and MD8 groups with no discernable side effects of the drugs.

We conclude that 4 mg D with M and 2 mg D with M is effective for prevention of nausea and vomiting, respectively, in patients at high risk for PONV undergoing LC.