Effects of granisetron in the treatment of nausea and vomiting after laparoscopic cholecystectomy: a dose-ranging study

BACKGROUND: Patients undergoing general anesthesia for laparoscopic cholecystectomy are at high risk for postoperative emetic symptoms (nausea, vomiting, and retching). Antihistamines, butyrophenones, dopamine receptor antagonists, and selective serotonin receptor antagonists (SSRAs) have been investigated for the prevention and treatment of emetic symptoms. However, these drugs are associated with undesirable adverse effects (AEs), such as excessive sedation, hypotension, dry mouth, dysphoria, hallucinations, and extrapyramidal signs. Granisetron hydrochloride is a newer SSRA developed for the prevention and treatment of cytotoxic drug-induced emetic symptoms, but its effects in postoperative laparoscopic cholecystectomy have not been studied. OBJECTIVE: The aims of this study were to assess the efficacy and tolerability of 4 doses of granisetron, and to determine the minimum effective dose, for the control of established emetic symptoms in patients undergoing general anesthesia for laparoscopic cholecystectomy. METHODS: This prospective, randomized, double-blind, placebo-controlled, dose-ranging study was conducted in the Departments of Anesthesiology and Surgery, Toride Kyodo General Hospital (Toride, Japan). Male and female patients aged 23 to 68 years with American Society of Anesthesiologists physical status I (no organic, physiologic, biochemical, or psychiatric disturbance) who were experiencing nausea lasting >10 minutes or retching or vomiting within 3 hours after recovery from general anesthesia for laparoscopic cholecystectomy were enrolled. Patients were randomized to receive a single IV dose of placebo or granisetron at 1 of 4 doses (10, 20, 40, or 80 microg/kg). Patients were monitored for 24 hours after study drug administration. RESULTS: One hundred patients (60 women, 40 men; mean SD] age, 48 10] years range, 23-68 years]; mean SD] height, 158 7] cm range, 145-177 cm]; mean SD] body weight, 56 8] kg range, 43-75 kg]) were enrolled. No significant differences in baseline demographic or clinical characteristics were found between the study groups. The proportions of patients who were free of emetic symptoms were significantly higher with granisetron 20, 40, and 80 microg/kg than with placebo (P = 0.02, 0.007, and 0.007, respectively). The difference between the granisetron 10-microg/kg group and the placebo group was not significant. No clinically significant AEs were reported in any group. CONCLUSIONS: Granisetron 20 microg/kg was the minimum effective dose for the treatment of established postoperative emetic symptoms in patients undergoing laparoscopic cholecystectomy. Increasing the dose to 80 microg/kg provided no further benefit.