Comparison of parenteral promethazine versus midazolam effect as a preoperative medication on postoperative nausea and vomiting after appendectomy

Postoperative nausea and vomiting is a high unpleasant symptom in surgical procedures. This study compares the effectiveness of midazolam with promethazine as multipurpose drug in postoperative nausea and vomiting as a preoperative and anesthetic medication after appendectomy. This randomized, double – blind clinical trial study was performed in patients who underwent appendectomy. These patients randomly received either placebo or midazolam or promethazine 5 minutes before appendectomy. All episodes of vomiting and nausea within 24 hours after surgery were recorded. The study population (N=75) comprised 3 comparable subgroups (N=25 in each group). A standard general anesthetic technique and postoperative analgesia were used. Data were collected and analyzed. Vomiting and nausea occurred in 19.20%, 0% and 81.80% of the patients in the midazolam, promethazine and placebo groups, respectively. The frequency of postoperative nausea and vomiting was as follows: the first 6 hours after surgery 0%, 0% and 50%, during the second 6 hours after surgery 19%, 0% and 19%, during the third 6 hours after surgery 0%, 0% and 7%, during the forth 6 hours after surgery 0%, 0% and 4% in the midazolam, promethazine and placebo groups, respectively. There were no significant differences between promethazine with midazolam in reduction of postoperative nausea and vomiting. Our study suggest that midazolam can be used as multipurpose drugs in postoperative nausea and vomiting as a preoperative medication after appendectomy and treatment using midazolam for anti-emetic prophylaxis provide a similar effect compared to promethazine in the present study.