Efficacy of ondansetron and metoclopramide for preventing postoperative emesis following strabismus surgery in children

A double-blind, randomised, placebo-controlled trial was conducted to compare the efficacy of metoclopramide with the 5-HT₃ antagonist, ondansetron, for the prevention of postoperative emesis in children undergoing elective strabismus surgery. None of the children received any premedication and a similar anaesthetic technique was used for all. Ondansetron 0.15 mg.kg⁻¹, metoclopramide 0.25 mg.kg⁻¹ or saline placebo were administered following intravenous catheter placement. Episodes of emesis were recorded for the first 24 h for the intervals of 0–2, 2–6 and 6–24 h. The incidence of emesis in the first 24 h was observed to be 71.7% in the placebo group, 34.4% in the ondansetron group (p < 0.001) and 61.4% in the metoclopramide group (p = NS). The severity of vomiting was less in the ondansetron group as compared with metoclopramide (p < 0.01) and placebo (p < 0.001). Recovery room scores were comparable in all the groups. No serious side-effects were observed in the ondansetron group. We conclude that prophylactic ondansetron is effective and superior to metoclopramide in the prevention of postoperative emesis in children following elective strabismus surgery.     

Metoclopramide versus ondansetron in prophylaxis of nausea and vomiting for laparoscopic cholecystectomy.

BACKGROUND: Postoperative nausea and vomiting are significant problems in laparoscopic surgery. This double-blind, randomized, prospective trial compares the prophylactic use of metoclopramide, ondansetron, and placebo for the treatment of postoperative nausea and vomiting in patients undergoing outpatient laparoscopic cholecystectomy. METHODS: Two hundred thirty-two patients aged 18 to 73 years were randomized into three groups. Patients received intravenously 10 mg of metoclopramide, 4 mg of ondansetron, or placebo in a double-blinded manner prior to surgery. RESULTS: The incidence of nausea was 32% for metoclopramide, 45% for ondansetron, and 44% for placebo in the postanesthesia care unit or day surgery, which was not statistically significant. The incidence of vomiting was 8% for metoclopramide, 4% for ondansetron, and 22% for placebo in the postanesthesia care unit or day surgery. These differences were statistically significant when comparing both drugs to placebo but not when comparing both drugs to each other. CONCLUSION: Prophylactic administration of metoclopramide or ondansetron significantly reduces the incidence of postoperative vomiting for laparoscopic cholecystectomy, but neither drug was found to be significantly more effective than the other. Metoclopramide is a more cost-effective treatment.     

Antiemetic prophylaxis in cardiac surgery: comparison of metoclopramide and ondansetron

We have compared the effectiveness of ondansetron (115 patients) and metoclopramide (101 patients) for prevention of postoperative nausea and vomiting in patients undergoing cardiac surgery involving cardiopulmonary bypass. In a prospective, randomized, controlled, double-blind study, patients received oral ondansetron 16 mg or oral metoclopramide 10 mg, 1-2 h before surgery. Anaesthesia was not standardized. Assessments of the severity of nausea and occurrence of vomiting were made at intervals after extubation and until discharge from the intensive care, or for a total of 24 h. Compared with the metoclopramide group, the ondansetron group had a higher incidence of nausea (49.6% vs 33.7%; P < 0.05) and vomiting (42.6% vs 24.8%; P < 0.01). There was no difference between groups in the number of patients who accepted postoperative antiemetics (ondansetron 43.4% vs metoclopramide 32.6%) and there was no difference in the incidence of symptoms of moderate or severe nausea.      

Oral ondansetron,tropisetron or metoclopramide to prevent postoperative nausea and vomiting: a comparison in high-risk patients undergoing thyroid or parathyroid surgery

BACKGROUND: Oral antiemetic prophylaxis may be a practical alternative to intravenous administration. Intravenous ondansetron and tropisetron prevent postoperative nausea and vomiting (PONV) at least as efficiently as traditional antiemetics, droperidol and metoclopramide. We tested the hypothesis that the incidence of PONV after oral ondansetron or tropisetron prophylaxis is lower compared with metoclopramide among high-risk patients. METHODS: In a prospective, double-blind study we studied 179 high-risk patients who received either ondansetron 16 mg, tropisetron 5 mg, or metoclopramide 10 mg orally 1 h before the operation. A standard general anesthetic technique and postoperative analgesia were used. The incidence of PONV and the need for rescue antiemetic medication was recorded for 24 h. RESULTS: In the postanesthesia care unit, the incidence of PONV was lower after premedication with tropisetron compared with ondansetron and metoclopramide (15%, 32% and 39%, respectively). The incidence of PONV during 0-24 h was the same in each group (68%, 58% and 75% in the ondansetron, tropisetron and metoclopramide group, respectively), but the incidence of vomiting was significantly lower after ondansetron (34%) and tropisetron (22%) prophylaxis compared with metoclopramide (53%). The need for additional antiemetics was significantly lower after tropisetron prophylaxis compared with metoclopramide. Patient satisfaction was significantly higher after tropisetron than after metoclopramide. CONCLUSIONS: In the initial period, the incidence of PONV was lower after premedication with oral tropisetron than after ondansetron or metoclopramide. Considering the entire 24-h postoperative period, the incidence of PONV was the same after all three premedications, but the incidence of vomiting was lower after oral ondansetron and tropisetron than after metoclopramide.     

Prophylactic anti-emetic efficacy of ondansetron in laparoscopic cholecystectomy under total intravenous anaesthesiaA randomised, double-blind comparison with droperidol, metoclopramide and placebo

The prophylactic anti-emetic efficacy and safety of pre-operative intravenous ondansetron was evaluated in a randomised, double-blind, comparison with droperidol, metoclopramide and placebo in 160 ASA grade 1 and 2 patients undergoing laparoscopic cholecystectomy under total intravenous anaesthesia. The patients were randomly allocated to receive ondansetron (4 mg), droperidol (1.25 mg), metoclopramide (10 mg) or placebo given as a single intravenous dose immediately before induction of a standardised general anaesthetic. There were no significant differences between the four study groups with regard to the demographic and anaesthetic data, postoperative analgesia, postoperative sedation scores, duration of postoperative hospital stay and incidence of adverse events. The incidence of nausea and vomiting was significantly lower (p < 0.05) between 1 h and 4 h after surgery in the ondansetron group compared with the droperidol, metoclopramide and placebo groups. The incidence of nausea was similar in the four groups in the other study periods: 0-1 h and 4-24 h. The incidence of vomiting was lower in the ondansetron, droperidol and metoclopramide groups than in the placebo group between 1 and 4 h but was the same between 4 and 24 h. As a result of the lower incidence of nausea and vomiting between 1 h and 4 h in the ondansetron group, the overall incidence of nausea and vomiting was lower during the first 24 h after surgery in this group than in the other three groups.     

Prophylacticiv ondansetron reduces nausea, vomiting and pruritus following epidural morphine for postoperative pain control

PURPOSE: To evaluate the prophylactic effect of ondansetron on nausea and vomiting following epidural morphine for postoperative pain control. METHODS: Seventy women (n = 35 in each group) undergoing abdominal total hysterectomy under epidural anesthesia were enrolled in this randomized, double-blinded, and placebo-controlled study. At the end of surgery, all patients received epidural morphine 3 mg for postoperative pain relief. Before morphine injection, the ondansetron group received iv ondansetron 4 mg, whereas the placebo group received iv saline. RESULTS: Patients in the ondansetron group reported a lower frequency of total postoperative nausea and vomiting (22%) and lower frequency of rescue antiemetic request (12%) than those in the placebo group (52% and 39%, respectively; P < 0.05). In addition, ondansetron was associated with a reduced incidence of pruritus following epidural morphine (28% vs 58%; P < 0.05). CONCLUSION: We conclude that iv ondansetron 4 mg is effective in the prevention of nausea, vomiting, and pruritus following epidural morphine for postoperative pain control.     

Comparing the efficacy of prophylactic metoclopramide, ondansetron, and placebo in cesarean section patients given epidural anesthesia

STUDY OBJECTIVE: To compare the relative efficacy of prophylactic metoclopramide, ondansetron, and placebo in nonemergent cesarean section patients given epidural anesthesia intraoperatively and for the first 24-hour period after delivery. DESIGN: Randomized, double blind, placebo-controlled study. SETTING: Inpatient obstetric unit at a university hospital center. PATIENTS: 164 nonemergent cesarean section patients given epidural anesthesia. INTERVENTION: At time of umbilical cord clamp, patients received intravenously (IV) either 4 mg ondansetron (Group O) or 10 mg metoclopramide (Group M) or 10 mL normal saline (Group P). MEASUREMENTS AND MAIN RESULTS: Episodes and severity of nausea and vomiting, rescue antiemetic requirement, patient satisfaction, and side effects were recorded. The frequency of intraoperative nausea were 24%, 43%, and 57% for Group O, Group M, and Group P, respectively (p < 0.03). The frequency of nausea for the 24-hour study period were 26%, 51% and 71% for Groups O, M, and P respectively (p < 0.03). The frequency of intraoperative and postoperative vomiting were similar between Group O and Group M, but significantly higher in Group P (p < 0.05). Overall patient satisfaction was highest in Group O compared with Groups P and M (p < 0.05). Maximum analog sedation score was higher in Group M compared to Groups O and P (p < 0.05). CONCLUSIONS: In cesarean section patients given epidural anesthesia, prophylactic ondansetron, 4 mg IV, is more efficacious and has a higher patient satisfaction than that with metoclopramide, 10 mg IV, or placebo in preventing nausea and achieving complete responses during intraoperative period and the first 24-hour postdelivery period. However, there is no difference between ondansetron and metoclopramide in reducing frequency of vomiting. Prophylactic ondansetron 4 mg IV is more effective in preventing nausea than vomiting.     

Ondansetron dose response curve in high-risk pediatric patients

Study Objective: To establish a dose-response relationship for ondansetron, and to evaluate any effects of oral premedication with metoclopramide in pediatric patients undergoing tonsillectomy and adenoidectomy and strabismus surgery.

Design: Prospective, randomized, double blind study.

Setting: University affiliated, 280-bed pediatric hospital.

Patients: 320 ASA physical status I and II patients between the ages of 2 and 12 years undergoing tonsillectomy and adenoidectomy or strabismus surgery.

Interventions: Patients were randomized to eight investigational groups. Patients in all eight groups underwent a standard anesthetic. Groups 1, 2, 3, and 4 received intravenous (IV) saline or IV ondansetron at doses of 0.05 mg/kg, 0.1 mg/kg and 0.15 mg/kg, respectively. Groups 5, 6, 7, and 8 received oral metoclopramide 0.15 mg/kg as well as IV saline, and ondansetron 0.05 mg/kg, 0.1 mg/kg, or 0.15 mg/kg. Patients were evaluated for emetic episodes prior to and following discharge.

Measurements and Main Results: All doses of ondansetron 0.05 mg/kg, 0.1 mg/kg, and 0.15 mg/kg were significantly more effective than placebo in reducing the incidence of emesis prior to, following discharge, and during the first 24 postoperative hours (p < 0.001). There were no significant differences in the occurrence of emesis between the groups receiving ondansetron 0.05 mg/kg, 0.1 mg/kg, and 0.15 mg/kg. The addition of oral metoclopramide 0.15 mg/kg had no effect on the incidence of emesis in the ondansetron or placebo study groups.

Conclusions: Ondansetron is an effective medication for the treatment and prevention of postoperative nausea and vomiting, and a dose of ondansetron 0.05 mg/kg is as effective as 0.1 mg/kg and 0.15 mg/kg. Metoclopramide 0.15 mg/kg has no effect on the incidence of postoperative nausea and vomiting.     

Nausea and vomiting after gynaecological laparoscopy: comparison of premedication with oral ondansetron, metoclopramide and placebo

We have compared the incidence of postoperative nausea and vomitingup to 48 h after day-case gynaecological laparoscopy after oralpremedication with ondansetron 4 mg, metoclopramide 10mg ora placebo allocated randomly and assessed blindly. Emetic symptoms(nausea or vomiting) occurred in 26% of patients who receivedondansetron, 42% of those who received metoclopramide and 50%of those given placebo.     

Ondansetron versus metoclopramide in prophylaxis of nausea and vomiting for laparoscopic cholecystectomy: a prospective double-blind randomized study

OBJECTIVE: Patients who undergo laparoscopic cholecystectomy may be at risk of experiencing postoperative nausea and vomiting. This prospective, randomized, double-blind study compared the prophylactic use of metoclopramide and ondansetron for the treatment of postoperative nausea and vomiting in patients who underwent elective laparoscopic cholecystectomy. METHODS: Eighty patients were randomized into two groups. Patients received ondansetron 4 mg or metoclopramide 10 mg intravenously in a double-blind manner at the end of anaesthesia. RESULTS: The incidence of nausea was 45% for metoclopramide and 20% for ondansetron in the 24 hours postoperatively; the difference was statistically insignificant (p = 0.05). Postoperative nausea score did not show any significant difference between the two group in the first 2 hours (p = 0.3) and 4 hours (p = 0.12) but was significant between 4 and 24 hours (p = 0.02). The incidence of vomiting was 20% for metoclopramide and 2.5% for ondansetron. This difference was statistically significant (p = 0.02). CONCLUSION: Ondansetron 4 mg given intravenously at the end of surgery is effective for preventing vomiting after laparoscopic cholecystectomy.     

Prevention of postoperative nausea and vomiting using ondansetron, a new, selective, 5-HT3 receptor antagonist.

The effect of ondansetron, a 5-HT3 antagonist, in preventing postoperative nausea and vomiting was investigated in a randomized, double-blind, placebo-controlled study of 84 patients undergoing gynecologic operation and receiving the same general anesthetic. The patients received premedication with either 16 mg oral ondansetron, or a matching placebo. The same medication was given postoperatively 8 h after the first dose. During the first hour after recovery from anesthesia, the frequencies of nausea and vomiting were 52% and 40%, respectively, in patients given placebos. In the ondansetron group nausea and vomiting developed in 17% and 12%, respectively, values significantly different from those with placebos (P less than 0.005). Similar differences were observed throughout the entire 24-h period after recovery, the incidence of nausea and vomiting being 67% and 60%, respectively, in the placebo group and 29% and 26% in the ondansetron treatment group. Ondansetron appears to be a promising antiemetic for the prevention of postoperative nausea and vomiting.     

L'ondansétron oral réduit-il l'incidence des nausées et vomissements après chirurgie du strabisme chez l'enfant ?

ObjectiveTo compare the efficacy of oral ondansetron with oral metoclopramide for the prevention of postoperative vomiting and nausea in children undergoing strabismus surgery.Study designProspective, randomized, double-blind trial.PatientsThirty children of physical class 1, age 9 ± 4 years, scheduled for strabismus surgery, were randomized into two groups (ondansetron and metoclopramide).MethodsIn the ondansetron group, the children received the first oral dose of ondansetron (4 mg) 1 hour before induction of anaesthesia and the other doses 8 and 16 hours later. In the metoclopramide group, children received metoclopramide (5 mg) in the same conditions. Anaesthesia was induced with thiopentone, vecuronium and fentanyl and maintained with halothane and N₂O/O₂. Patients were evaluated by an independent observer for nausea and emesis in recovery room (0–2 h) and on the ward. The adverse effects of oral ondansetron and metoclopramide were assessed.ResultsThere were non-significant differences between the two groups for incidence of nausea and vomiting (40% and 53% in ondansetron group versus 33 and 60% in metoclopramide group, respectively).ConclusionUnlike intravenous ondansetron, oral ondansetron is not superior to metoclopramide for the prevention of nausea and vomiting caused by strabismus surgery in children.     

Prophylactic antiemetic therapy with ondansetron,tropisetron, granisetron and metoclopramide in patients undergoing laparoscopic cholecystectomy: a randomized,double-blind comparison with placebo

Purpose

Postoperative nausea and vomiting (PONV) is a distressing adverse effect of general anaesthesia. The aim of the current study was to compare the antiemetic activity of different 5-hydroxytryptamine₃ receptor antagonists with that of metoclopramide and placebo.

Methods

In a prospective, randomized, double-blind study we have compared the antiemetic activity of the prophylactic administration of ondansetron 4 mg, tropisetron 5 mg and granisetron 3 mg with that of metoclopramide 10 mg and placebo in 132 patients undergoing laparoscopic cholecystectomy. All study drugs and placebo were given as a short iv infusion ten minutes before the induction of anaesthesia. Perioperative anaesthetic care was standardized in all patients. Nausea and vomiting were assessed by direct questioning of the patient at 1, 4, 9, 12, 18 and 24 hr after recovery from anaesthesia. If patients experienced nausea and/or vomiting, rescue antiemetic treatment (metoclopramide 10 mg iv) was administered.

Results

For the 24-hr recovery period after surgery, the percentages of emesis-free patients were 65.5%, 52%, 48%, 29.2% and 27.6% in the ondansetron, granisetron, tropisetron, metoclopramide and placebo groups, respectively. Prophylactic antiemetic treatment with ondansetron resulted in a lower incidence (P = 0.02) of PONV than with metoclopramide or placebo. The times at which rescue antiemetic was first received were longer (P < 0.01) in ondansetron group than in the placebo and metoclopramide groups. There were no statistical differences between ondansetron, tropisetron and granisetron groups.

Conclusions

Ondansetron, when given prophylactically resulted in a significantly lower incidence of PONV than metoclopramide and placebo. Metoclopramide was ineffective.     

Comparison of oral dolasetron and ondansetron in the prophylaxis of postoperative nausea and vomiting in children

BACKGROUND AND OBJECTIVE: In a randomized, placebo-controlled, double-blind trial, we compared the efficacy of oral dolasetron and ondansetron in preventing postoperative nausea and vomiting in children after various surgical operations. METHODS: Children were assigned randomly to one of three groups (each contained 50 children) to receive dolasetron 1.8 mg kg(-1) or ondansetron 0.15 mg kg(-1) orally, or a placebo. All children received methylene blue capsules (10 mg) orally as an indicator before the induction of anaesthesia. Postoperatively, contamination of the mouth and the endotracheal tube by methylene blue was recorded, and postoperative nausea and vomiting was recorded for 0-1, 1-24 and 0-24 h. Metoclopramide (0.1 mg kg(-1)) intravenously was used as the rescue antiemetic. RESULTS: In the 0-1 h period after operation, there were no differences between the groups. In the 1-24 h period, dolasetron was significantly better than placebo (nausea 8 versus 24%; vomiting 4 versus 20%; total nausea and vomiting scores 16 versus 48%). Over the 0-24 h period, both dolasetron and ondansetron were significantly better than placebo (nausea 16 versus 26 versus 40%), vomiting (8 versus 16 versus 30%), and total nausea and vomiting scores (32 versus 48 versus 78%). There were no significant differences between dolasetron and ondansetron. There was no important methylene blue contamination, and little use of rescue metoclopramide. There were no important adverse events. CONCLUSIONS: Prophylactic oral dolasetron and ondansetron were effective in reducing postoperative nausea and vomiting in children.     

A singleiv dose of ondansetron 8 mg prior to induction of anaesthesia reduces postoperative nausea and vomiting in gynaecological patients

The effect of a single intravenous dose of ondansetron in preventing postoperative nausea and emesis (retching and vomiting) (PONV) was investigated in a randomized, double-blind, placebo-controlled, multicentre, international study. Women of ASA class I–III, requiring gynaecological laparotomy, vaginal hysterectomy, or major vaginal surgery were selected for study. Two hundred and thirty-five received placebo, 231 received 1 mg ondansetron, 228 received 8 mg ondansetron and 229 received 16 mg ondansetron, as an infusion over five minutes before the induction of anaesthesia. A standardized balanced anaesthetic technique was employed. This consisted of premedication with either diazepam or temazepam, thiopentone induction, maintenance with nitrous oxide in oxygen supplemented with enflurane or isoflurane, intraoperative analgesia with fentanyl, neuromuscular blockade with any choice of agent and reversal with neostigmine and atropine. Postoperative analgesia was achieved with morphine, and prochlorperazine or metoclopramide were given if a rescue antiemetic was required. A greater percentage of patients in the 8 mg and 16 mg ondansetron groups experienced no postoperative emesis (44% and 39% respectively) than in the placebo and 1 mg ondansetron groups (29% and 28% respectively) for the first 24 hr postoperative period (8 mg vs placebo and 1 mg: P ≤ 0.001; 16 mg vs placebo: P < 0.05; 16 mg vs 1 mg: P < 0.05). Similarly, the percentage of patients who did not experience postoperative nausea were 20%, 26%, 31% and 28% for the placebo, 1 mg, 8 mg and 16 mg ondansetron treatment groups, respectively (8 mg and 16 mg vs placebo P < 0.05). Overall, the incidences of adverse events in the ondansetron and placebo groups were similar. It is concluded that intravenous ondansetron, at doses of 8 mg and 16 mg, is both well tolerated and effective in preventing postoperative nausea and emesis, and no greater benefit was observed with the 16 mg dose in comparison with the 8 mg dose.     

不同止吐药预防术后PCA恶心呕吐的临床观察

目的　探讨各种止吐药预防术后芬太尼静脉PCA恶心呕吐的效果。方法　选择硬膜外麻醉下行开腹手术患者 83例 ,术毕接PCA泵行芬太尼静脉PCA(PCIFA)。并随机分成四组 ,C组 :不给止吐药 ;M组 :甲氧氯普胺 10mg ;O组 :恩丹西酮 8mg ;N组 :欧必亭 5mg。 结果　N组术后12小时和 2 4小时止恶心、呕吐作用均明显优于其他三组 ;恶心、呕吐发生率O组仅于术后 12小时稍有降低 ,而N组术后 12和 2 4小时下降均明显。结论　欧必亭与恩丹西酮、甲氧氯普胺比较 ,能更有效地防治PCIFA引起的恶心、呕吐     

A comparison of prophylactic ondansetron and metoclopramide administration in patients undergoing major neurosurgical procedures

In a prospective, randomised, double-blind trial, we assessed the relative efficacy of prophylactic ondansetron and metoclopramide administration in the reduction of postoperative nausea and vomiting in 60 patients undergoing routine major neurosurgical procedures. The patients were randomly allocated into one of two groups. Both groups received a standardised anaesthetic. When the dura mater was closed, patients in group A received an intravenous injection of metoclopramide 10 mg whilst group B received ondansetron 8 mg intravenously. Patients who received metoclopramide experienced less postoperative nausea and vomiting than those who received ondansetron in the 48 h following surgery (17 (56%) versus 9 (30%) p = 0.038). In the light of these findings, we believe that ondansetron is an inappropriate agent for the prevention of postoperative nausea and vomiting in the neurosurgical population.     

Olanzapine as an add-on,pre-operative anti-emetic drug for postoperative nausea or vomiting: a randomised controlled trial

Postoperative nausea or vomiting occurs in up to 40% in patients with multiple risk factors, despite prophylaxis. Olanzapine is an antipsychotic drug that is used to prevent nausea and vomiting in palliative care and to treat chemotherapy-induced nausea and vomiting. This study aimed to examine whether pre-operative olanzapine, as a prophylactic anti-emetic added to intra-operative dexamethasone, ondansetron and total intravenous anaesthesia, reduced the incidence of postoperative nausea or vomiting. We performed a multiply-blinded randomised controlled trial in patients aged 18–60 years with cancer at high risk of postoperative nausea or vomiting (three or four risk factors according to the Apfel criteria) plus a previous history of chemotherapy-induced nausea and vomiting. Patients were allocated at random to receive 10 mg olanzapine or placebo orally 1 h before surgery in addition to a two-drug regimen (dexamethasone and ondansetron) and propofol anaesthesia to prevent postoperative nausea or vomiting. The primary outcome was the incidence of postoperative nausea or vomiting in the first 24 h after surgery. In total, 100 patients were enrolled; 47 in the olanzapine group and 49 in the control group completed the study. The baseline characteristics of the groups were similar. The incidence of postoperative nausea or vomiting in the first 24 h after surgery was lower in the olanzapine group (12/47, 26%) than in the control group (31/49, 63%) (p = 0.008, RR 0.40 (95%CI 0.21–0.79)). Adding pre-operative oral olanzapine to intra-operative dexamethasone and ondansetron was highly effective in reducing the risk of postoperative nausea or vomiting in the first 24 hours after surgery in patients with a previous history of chemotherapy-induced nausea and vomiting and at least three Apfel risk factors for postoperative nausea or vomiting.     

Efficacy of orally disintegrating ondansetron in preventing postoperative nausea and vomiting after laparoscopic cholecystectomy: a randomised, double-blind placebo controlled study

Peri-operative prophylactic anti-emetics are commonly used parenterally. Orally disintegrating ondansetron is efficacious during chemotherapy. Therefore, we aimed to study the efficacy of orally disintegrating ondansetron for postoperative nausea and vomiting. In a randomised, double-blind, placebo controlled trial on 109 patients scheduled for laparoscopic cholecystectomy, oral ondansetron was compared to intravenous ondansetron and placebo. The anaesthetic technique was standardised. Mean time (SD) to tolerating oral intake was delayed in the placebo group to 366.1 (77.6) min compared to oral 322.9 (63.7) min and intravenous 322.4 (65.2) min groups. This is corroborated by a higher incidence of nausea and vomiting in the control group during the first 6 h postoperatively (control 44.4%, oral 17.7%, intravenous 18.2%). There was no significant difference between oral and intravenous groups. In conclusion, orally disintegrating ondansetron was as efficacious as intravenous ondansetron in the peri-operative phase and may be a viable option for prophylaxis of emesis in day care surgery.     

Prevention of postoperative nausea and vomiting by ondansetron]

This study was carried out to assess the efficacy of oral ondansetron, a new 5HT3 receptor antagonist, in patients undergoing thyroid surgery. It included 60 patients, randomly assigned to two groups, and receiving orally, 1 h before induction of anaesthesia, either 8 mg of ondansetron (n = 29) or a placebo (n = 30). One patient was excluded. The same anaesthetic protocol, consisting of 3 to 5 micrograms.kg-1 of fentanyl, 4 to 6 mg.kg-1 of thiopentone, and 0.5 mg.kg-1 of atracurium, was used in all. Anaesthesia was maintained with 50% nitrous oxide in oxygen with 0.8 to 1% endtidal concentration of isoflurane and additional boluses of 0.1 mg of fentanyl as required. The incidence and intensity of nausea, graded mild, moderate or severe, and the incidence of vomiting were recorded postoperatively. During the first twelve hours after surgery, 40% of patients in the placebo group had nausea (16.7% mild, 20% moderate and 6.7% severe), and 50% vomited. In the ondansetron group, nausea and vomiting occurred in 13.8% and 20.4% of patients respectively. The 4 patients in the latter group complained of major nausea. The differences between the groups were statistically significant: p = 0.025 for nausea and p = 0.042 for vomiting. It is concluded that oral ondansetron, 8 mg taken orally 1 h before surgery, significantly reduces the incidence of nausea and vomiting during the first twelve postoperative hours. As it is easy to use and has no side-effects, it might be of interest in day-case surgery patients, despite its high cost.