A randomized, double-blind pilot study examining the use of intravenous ondansetron in the prevention of postoperative nausea and vomiting in female inpatients.

STUDY OBJECTIVE: To compare the efficacy and safety profiles of intravenous (IV) ondansetron (two 8 mg doses 8 hours apart) and a placebo when used in the prevention of postoperative nausea and emesis (vomiting or retching). DESIGN: Randomized, double-blind, placebo-controlled, parallel, multicenter pilot study. SETTING: Four university hospitals in the United States. PATIENTS: Two hundred seven women scheduled to undergo inpatient surgical procedures during general anesthesia. INTERVENTIONS: Patients were randomized to receive, in a double-blind fashion, either two 8 mg doses of IV ondansetron or a placebo. The first study drug dose was administered before induction of anesthesia; the second dose was given 8 hours later. Each study drug dose was admixed with normal saline to 20 ml and administered IV over 2 to 5 minutes. Vital signs were monitored immediately before and 1 minute after completion of the study drug infusion. MEASUREMENTS AND MAIN RESULTS: For the 24-hour period following operation, 60% of the patients who received ondansetron and 26% of the patients who received the placebo were emesis-free (p < 0.001). Subanalyses based on patients' previous history of general anesthesia indicated that ondansetron was superior to the placebo in preventing emesis regardless of history [66% vs. 33% in patients who had never had general anesthesia or had had no nausea or emesis following previous anesthesia (p = 0.001) and 50% vs. 17% in patients who had nausea or emesis following previous anesthesia (p = 0.005)]. Ondansetron also was superior to the placebo for the prevention of nausea over the 24-hour study period regardless of anesthesia history. Ondansetron was generally well tolerated. The adverse event, vital sign, and clinical laboratory test profiles were similar to those for the placebo. No patient who received ondansetron had untoward changes in central nervous system function, including sedation. CONCLUSIONS: Prophylactic IV ondansetron appears to be safe and causes a significant reduction in the frequency and severity of postoperative nausea and emesis.

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.

Ondansetron in the treatment of postoperative nausea and vomiting in ambulatory outpatients: a dose-comparative, stratified, multicentre study.

The safety and efficacy of ondansetron were evaluated in the treatment of postoperative nausea and vomiting. Five hundred patients who experienced nausea or vomiting in the Post-Anaesthesia Care Unit within the first 2 h of recovery were randomized to receive either 1, 4, or 8 mg of ondansetron, or placebo. All patients had undergone ambulatory surgery with general endotracheal anaesthesia. Episodes of emesis, nausea scores, adverse events, vital signs, and laboratory values were assessed before and during the 24 h after study drug administration. Patients were evaluated for the first 2 h in the Post-Anaesthesia Care Unit then followed up for the next 22 h. Complete response was defined as no emetic episodes, no nausea or no rescue anti-emetic medication. For the 0-24 h study period, complete response occurred in only 15% of the placebo group compared to 41%, 47%, and 47% in the 1, 4, and 8 mg ondansetron groups, respectively. Mean nausea scores (scale of 0-10) during the initial observation period (0-2 h) were significantly lower for all doses of ondansetron [2.2 (1 mg), 1.7 (4 mg), and 2.1 (8 mg)] compared to placebo (3.0). The optimal dose of ondansetron for the treatment of postoperative nausea and vomiting was found to be 4 mg. All doses of ondansetron were well tolerated. No clinically significant increases in laboratory parameters or alterations in haemodynamic stability occurred in the ondansetron groups compared to placebo.

Induced hypotension with labetalol for orthognathic surgery.

Induced hypotension is an accepted technique for reducing blood loss in various surgical procedures. This study evaluates the effectiveness of labetalol in producing controlled reduction in mean arterial pressure during orthognathic surgery. The potential advantages of this technique are ease of administration, decreased pulmonary shunting, and absence of tachycardia or rebound hypertension compared to other commonly used agents.