Granisetron versus tropisetron in the prevention of postoperative nausea and vomiting after total thyroidectomy

ABSTRACT

Postoperative nausea and vomiting [PONV] are frequently encountered after thyroidectomy. For PONV prevention, selective serotonin 5-hydroxytryptamine type 3 [5-HT [3]] receptor antagonists are considered one of the first-line therapy. We report on the efficiency of granisetron and tropisetron, with that of placebo on the prevention of PONV in patients undergoing total thyroidectomy. One hundred twenty-seven patients were divided into three groups and randomized to receive intravenously, prior to induction of anesthesia, tropisetron 5 mg, or granisetron 3 mg, or normal saline. All patients received additionally 0.625 mg droperidol. All episodes of postoperative PONV during the first 24 h after surgery were evaluated. Nausea visual analogue scale [VAS] score was lower in tropisetron and granisetron groups than the control group at all measurements [P<0.01] except for the 8-h measurement for tropisetron [P=0.075]. Moreover, granisetron performed better than tropisetron [P<0.011 at 4 h and P<0.01 at all other points of time] apart from the 2-h measurement. Vomiting occurred in 22.2%, 27.5%, and 37.5% in granisetron, tropisetron, and control groups, respectively [P=0.43]. The combination of the 5-HT[3] antagonists with droperidol given before induction of anesthesia is well tolerated and superior to droperidol alone in preventing nausea but not vomiting after total thyroidectomy