Intravenous ondansetron for postsurgical opioid-induced nausea and vomiting. S3A-255 Study Group.

The use of opioids for postoperative analgesia may be limited by side effects such as nausea and vomiting. Because ondansetron, a selective serotonin type 3 (5-hydroxytryptamine [5-HT3]) antagonist, is effective for chemotherapy and general anesthesia-induced nausea and vomiting, we hypothesized that it may also be effective for opioid-induced nausea and vomiting. ASA physical status I-III patients undergoing regional anesthesia were eligible for the study. Those who requested an antiemetic after postsurgical opioid administration were randomized to receive a single dose of ondansetron (0.1 mg, 4 mg, or 16 mg intravenously [I.V.]) or placebo in a double-blind fashion. Emetic episodes, nausea and pain ratings, and adverse events were recorded for 24 h after study drug administration. Patient satisfaction scores were obtained 24 h after study drug infusion. A significantly (P < 0.05) larger proportion of patients treated with ondansetron 4 mg and 16 mg experienced no emetic episodes, received no rescue antiemetic, and completed the study compared with placebo. Nausea scores and patient satisfaction scores in the ondansetron 16-mg group were significantly (P < 0.05) more favorable than in the placebo group. Postsurgical pain scores did not differ among groups. The incidence of adverse events was similarly low across groups. The results of this study support our hypothesis that I.V. ondansetron is effective for postsurgical opioid-induced nausea and vomiting.

Single dose intravenous ondansetron for the 24-hour treatment of postoperative nausea and vomiting.

Postoperative nausea and vomiting is a major concern for patients undergoing outpatient surgery under general anaesthesia, and may complicate and delay discharge from hospital. This paper evaluates the safety and efficacy of ondansetron, a 5-HT3 receptor antagonist, in the treatment of postoperative nausea and vomiting. One thousand patients in 30 centres in the United States who received general anaesthesia and developed postoperative nausea and vomiting were studied. In a randomised, double-blind, stratified and parallel designed protocol, patients received either ondansetron 1, 4, 8 mg or placebo for nausea or vomiting occurring within 2 h of entry into the Post Anaesthesia Care Unit. Subsequent episodes of vomiting, nausea scores, laboratory and clinical safety data and adverse events were evaluated during the 24-h study period. In a separate study, pharmacokinetic data were compared for intramuscularly and intravenously administered ondansetron. Each dose of ondansetron was significantly better than placebo in reducing nausea from control values during the initial 2-h study period, and in preventing further emesis over 24 h. There were no significant differences in the incidence of adverse events, changes in laboratory values or measures of vital signs in the ondansetron groups compared to the placebo group. Dose comparisons between the three treatment groups showed that ondansetron 4 mg is the optimal dose to treat postoperative nausea and vomiting. Ondansetron is a well tolerated, efficacious antiemetic which has a similar side effect profile to placebo. Intramuscular administration has the same systemic availability as intravenous administration.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of postoperative nausea and vomiting after outpatient surgery with the 5-HT3 antagonist ondansetron.

BACKGROUND: Postoperative nausea and vomiting following outpatient surgery can significantly delay discharge. This study evaluates the safety and efficacy of ondansetron (a new 5-HT3 antagonist) in the treatment of postoperative nausea and vomiting in patients following outpatient surgery. METHODS: Five hundred outpatient surgical patients (53 male and 447 female), receiving general endotracheal anesthesia, were studied at ten centers. Patients were stratified by gender and received, in a randomized, double-blind manner, 1, 4, or 8 mg ondansetron or placebo in response to nausea and/or vomiting postoperatively. Episodes of vomiting, nausea scores, adverse events, vital signs, and laboratory values were evaluated before and during the 24 h after study drug administration. RESULTS: Complete response to study medication (no vomiting and/or retching, and no rescue antiemetic over the initial 0-2-h period) was more frequent in the ondansetron groups (1 mg 57%, 4 mg 61%, and 8 mg 57%) than in the placebo group (30%, P < .001). For the 0-24-h study a complete response occurred in only 15% of the placebo group compared to 41%, 47%, and 47% of the 1-, 4-, and 8-mg ondansetron groups, respectively (P < .001 for all comparisons with placebo). Median nausea scores (range 0-10) during the initial observation period (0-2 h) were significantly lower for all doses of ondansetron (1.3, 0.8, 1.8 for 1, 4, and 8 mg, respectively) as compared with placebo (2.3). No significant differences occurred in hemodynamic stability, incidence of adverse events, or changes in laboratory values in the ondansetron groups compared to the placebo group. CONCLUSIONS: Ondansetron, in doses less than 8 mg, is a safe, effective antiemetic for treating postoperative nausea and vomiting.