Oral clonidine premedication does not reduce postoperative vomiting in children undergoing strabismus surgery

BACKGROUND: We evaluated the effect of oral clonidine on postoperative vomiting (POV) in children undergoing strabismus surgery. METHODS: Eighty ASA physical status I children aged 3-12 years were randomly assigned to one of two groups in a double-blinded manner. One hour before surgery, each patient in the clonidine group (n=40) received clonidine 4 micro g kg-1 in apple juice 0.2 ml kg-1, and each of the controls (n=40) received apple juice 0.2 ml kg-1 only. The protocol for general anesthesia was propofol-sevoflurane in N2O/O2. A paracetamol suppository was administered in each case to prevent postoperative pain. Patient responses during 0-48 h after anesthesia were recorded as complete (no POV, no antiemetic rescue required), retching, vomiting, or rescue antiemetic. RESULTS: There were no significant differences between the clonidine and control groups regarding the number of patients with complete response (21 vs. 18, respectively) retching (10 vs. 14, respectively), vomiting (19 vs. 22, respectively), or rescue antiemetic (9 vs. 12, respectively) during the first 48 h. CONCLUSION: Oral premedication with clonidine 4 micro g kg-1 did not reduce the rate of POV in the children undergoing strabismus surgery.     

Preoperative oral granisetron for the prevention of vomiting following paediatric surgery

BACKGROUND: We evaluated the efficacy of granisetron, 5-hydroxytryptamine type 3 receptor antagonist, given orally, preoperatively, for the prevention of postoperative vomiting in children undergoing general anaesthesia for surgery (inguinal hernia, phimosis-circumcision). METHODS: In a randomized, double-blinded manner, 100 children, ASA physical status I, aged 4-11 years, received orally placebo or granisetron at three different doses (20 microg x kg(-1), 40 microg x kg(-1), 80 microg x kg(-1)) 60 min before surgery (n=25 of each). The same standard general anaesthetic technique was used. RESULTS: The percentage of patients being emesis-free during 0-6 h after anaesthesia was 56% with placebo, 64% with graniseron 20 microg x kg(-1) (P=0.773), 88% with granisetron 40 microg x kg(-1) (P=0.027) and 92% with granisetron 80 microg x kg(-1) (P=0.01); the corresponding rate during 6-24 h after anaesthesia was 60%, 68% (P=0.768), 92% (P=0.02) and 92% (P=0.02) (P-values versus placebo). No clinically serious adverse events were observed in any of the groups. CONCLUSIONS: In summary, preoperative oral granisetron 40 microg x kg(-1) is effective for the prevention of vomiting following paediatric surgery (inguinal hernia, phimosis-circumcision). Increasing the doses to 80 microg x kg(-1) provides no demonstrable additional benefit.     

Oral clonidine premedication reduces vomiting in children after strabismus surgery

This is a prospective randomized double-blind trial conducted to determine whether preoperative orally administered clonidine causes or potentiates postoperative vomiting in 140 children (3–12 yr) undergoing strabismus surgery. They were all inpatients and classified randomly into four groups (n = 35 each); placebo (control), diazepam 0.4 mg · kg^?1, clonidine 2 μg · kg^?1, and clonidine 4 μg · kg^?1. These agents were administered 93–112 min (mean: 100 min) before the anticipated time of induction of anaesthesia. All children received inhalational anaesthesia with halothane and nitrous oxide in oxygen.’ Muscle relaxation in all patients was obtained with vecuronium and residual neuromuscular blockade was antagonized with neostigmine and atropine before tracheal extubation. Diclofenac suppository was prescribed to prevent postoperative pain. No opioids or postoperative antiemetics were administered. All children remained in hospital for two days postoperatively. The incidence and frequency of vomiting were compared in the groups with Kruskall-Wallis Rank test. Clonidine 4 μg · kg^?1 caused a lower incidence and frequency of vomiting than did placebo and diazepam (incidence and frequency: 11% and 1,37% and 3, and 34% and 2 in clonidine 4 μg · kg^?1, placebo, and diazepam, respectively; P < 0.05 for clonidine 4 μg · kg^?1 vs placebo and diazepam). However, lowdose clonidine was ineffective. These data suggest that preanaesthetic medication with clonidine 4 μg · kg^?1 may be useful for preventing emesis following strabismus surgery. This property of clonidine indicates that it may be superior to other sedative premedicants such as diazepam and midazolam.     

Incidence of vomiting in susceptible children under regional analgesia with two different anaesthetic techniques

BACKGROUND: Postoperative vomiting (POV) is a frequent side-effect of paediatric surgery and a leading cause of unplanned admission. Many antiemetic drugs have been studied, but less attention has been given to the effects on POV of the anaesthetic technique adopted. The aim of this study was to compare two different anaesthetic techniques in children under regional analgesia at risk for POV. METHODS: We studied 135 children suffering from motion sickness or with a previous history of POV. The patients were randomized to receive inhalation anaesthesia (group S) with sevoflurane by LMA or intravenous (i.v.) anaesthesia with ketamine and propofol (group P). All the patients were treated with an ilio-inguinal block after induction of anaesthesia. Postoperatively, the children were followed by the nursing staff and by their parents, none of whom were aware of the anaesthesia technique used. RESULTS: A significant decrease was observed in the incidence of early (0-6 h) and delayed (6-24 h) POV in those children who received i.v. sedation. There was no difference between the two groups in the level of analgesia either at the end of surgery or 2 h postoperatively. CONCLUSIONS: Anaesthesia based on propofol and ketamine is better than inhalation anaesthesia with sevoflurane by LMA for reducing POV in children at risk under an ilio-inguinal block. Tailoring the anaesthetic to the specific needs of children susceptible to POV should be considered before resorting to the routine use of expensive antiemetic prophylaxis.     

Pretreatment with oral clonidine attenuates cardiovascular responses to tracheal extubation in children

This study was designed to evaluate the effects of diazepam and clonidine orally given preoperatively on cardiovascular responses to tracheal extubation in children. Fifty children, ASA physical status I, aged 4-10 years, undergoing minor elective surgery (inguinal hernia, phimosis) received orally, in a randomized, double-blind manner, diazepam 0.4 mg.kg-1 or clonidine 4 microgram.kg-1 (n=25 of each). These drugs were administered 105 min before an inhalational induction of anaesthesia. The same standard general anaesthetic technique was employed throughout. The maximum changes in heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP) were less in patients who had received clonidine than in those who had received diazepam (HR, 12 vs 24; SBP, 14 vs 26; DBP, 9 vs 16; mean, P < 0.05). In conclusion, compared to diazepam given orally, pretreatment with oral clonidine attenuates haemodynamic changes associated with tracheal extubation in children.     

The effect of remifentanil or fentanyl on postoperative vomiting and pain in children undergoing strabismus surgery

Postoperative vomiting (POV) after strabismus surgery in children results in discomfort and prolonged hospital stays. Opioids increase the incidence of POV. Remifentanil has a context-sensitive half-life of 3 to 4 min, and how this short half-life influences POV in those patients is unknown. We conducted a prospective, double-blinded study in 81 ASA status I or II children from 2 to 12 yr of age undergoing elective strabismus surgery under general anesthesia. Patients were randomized to receive either remifentanil (bolus 1 microg/kg; infusion 0.1-0.2 microg x kg(-1) x min(-1)) or fentanyl (2 microg/kg, and 1 microg/kg every 45 min). POV episodes were recorded for 25 h. Pain scores were obtained by using an objective pain scale for 60 min during recovery. The number of patients who experienced POV did not differ significantly between groups (49% vs 48%). However, in the Remifentanil group, POV episodes were significantly less frequent (0.95 vs 2.2 episodes). In contrast, fentanyl was associated with lower pain scores during the first 30 min of recovery. We conclude that children undergoing strabismus surgery under balanced anesthesia with remifentanil, compared with fentanyl, showed less frequent POV. However, early postoperative analgesia was better with fentanyl. IMPLICATIONS: Opioids increase the incidence of postoperative vomiting (POV). Remifentanil is characterized by the shortest half-life of all opioids used in anesthetic practice. Therefore, we studied the effect of remifentanil on POV compared with the longer-acting opioid fentanyl in children undergoing strabismus surgery.     

Diclofenac and flurbiprofen with or without clonidine for postoperative analgesia in children undergoing elective ophthalmological surgery

We conducted a prospective, randomized study to compare the efficacy of preoperative diclofenac, flurbiprofen, and clonidine, given alone, as well as the combination of diclofenac and clonidine, and flurbiprofen and clonidine in controlling postoperative pain in 125 children. The patients (ASA I, 2-12 years) undergoing elective ophthalmological surgery were allocated to one of five groups: rectal diclofenac 2 mg.kg(-1) following oral placebo premedication, i. v. flurbiprofen 1 mg.kg(-1) following placebo premedication, oral clonidine premedication, rectal diclofenac 2 mg.kg(-1) following clonidine, and i.v. flurbiprofen 1 mg.kg(-1) following clonidine. The children received clonidine (4 microg.kg(-1)) or placebo 105 min before anaesthesia. Diclofenac or flurbiprofen was given immediately after induction of anaesthesia. Anaesthesia was induced and maintained with sevoflurane and nitrous oxide in oxygen. Postoperative pain was assessed by a blinded observer using a modified objective pain scale (OPS). No opioids were administered throughout the study. Rectal diclofenac 2 mg.kg(-1) i.v. flurbiprofen 1 mg.kg(-1), oral clonidine 4 microg.kg(-1) provided similar OPS scores and requirement for supplementary analgesics during 12 h after surgery. Combination of oral clonidine and one of these nonsteroidal analgesics minimized postoperative pain. Our findings suggest that this combined regimen may be a promising prophylactic approach to postoperative pain control in children undergoing ophthalmological surgery.     

Combination of granisetron and droperidol for the prevention of vomiting after paediatric strabismus surgery.

This study was undertaken to compare the efficacy of granisetron plus droperidol with each antiemetic alone for the prevention of vomiting after paediatric strabismus surgery. In a prospective, randomized, double-blinded trial, 120 ASA physical status I children, aged 4-10 years, received granisetron 40 microg.kg- 1, droperidol 50 microg.kg- 1, granisetron 40 microg.kg- 1 plus droperidol 50 microg.kg- 1 (n=40 of each) intravenously after an inhalation induction of anaesthesia. A complete response, defined as no vomiting, no retching and no need for another rescue antiemetic medication, during 0-3 h after anaesthesia was 80% with granisetron, 45% with droperidol and 98% with granisetron plus droperidol, respectively; the corresponding incidence during 3-24 h after anaesthesia was 78%, 38% and 98% (P< 0.05; overall chi-squared test with Yates continuity correction). No clinically important adverse events were observed in any of the groups. In conclusion, a combination of granisetron and droperidol was more effective than granisetron or droperidol as a sole antiemetic for the prevention of postoperative vomiting in children undergoing strabismus repair.     

Effect of timing of ondansetron administration on incidence of postoperative vomiting in paediatric strabismus surgery

This prospective, randomized, double-blinded study evaluated the effect of the timing of ondansetron administration on its antiemetic efficacy in children undergoing elective strabismus surgery. One hundred and twenty children aged one to 15 years, ASA physical status 1 or 2, were randomly allocated to receive intravenous ondansetron 100 micrograms/kg either at induction (Group 1) or at the end of the surgery (Group 2). All patients had general anaesthesia induced and maintained with nitrous oxide and halothane, muscle relaxation with vecuronium, endotracheal intubation, reversal with neostigmine and glycopyrrolate, and pethidine 0.5 mg/kg analgesia. Episodes of nausea and vomiting were evaluated at 0 to 2, 2 to 6 and 6 to 24 hour intervals by a blinded observer. Demographic data, duration of anaesthesia, type of surgery, incidence of previous postoperative nausea or vomiting and motion sickness and number of patients who developed oculocardiac reflex requiring atropine treatment were similar in both groups. The incidence of emesis in the first 24 hours following surgery was similar in both groups (35% Group 1, 33.3% Group 2, P = 1.00). Severity of emesis (median number of emetic episodes, rescue antiemetic requirement and mean time to the onset of first episode of emesis) and mean time to discharge from the post anaesthesia care unit were also similar in the two groups. We conclude that the timing of ondansetron administration either before or after the surgical manipulation of extraocular muscles had similar antiemetic efficacy following strabismus surgery in children.     

The prevention of postoperative vomiting following strabismus surgery in children

Children recovering from anaesthesia for strabismus surgery are particularly prone to nausea and vomiting as a result of intraoperative vagus irritation. Besides being disturbing to the patient, vomiting can be dangerous during emergence from anesthesia and can result in delayed discharge. Droperidol is a powerful antiemetic drug that has been shown to reduce the incidence and severity of postoperative nausea and vomiting in pediatric strabismus patients, although the best timing for administration is not clear. MATERIAL AND METHODS. We compared three randomized groups totalling 61 patients. Droperidol 0.075 mg/kg i.v. was given either at induction of anesthesia after intubation (n = 20) or during the last muscle suture (n = 21). The third group received no antiemetic treatment. The patients' ages ranged from 3 to 14 years (mean 5.9 +/- 2.84 years). There was no difference in age or sex between the three groups. Anesthesia was standardized with rectal midazolam premedication, atropine, thiopental, succinylcholine, O2/N2O = 1:2, enflurane, intubation, and a gastric tube. RESULTS. Nausea, retching, or vomiting occurred in 2/20 children (10%) given droperidol preoperatively, 4/21 children (19%) with droperidol during the operation, and 9/20 children (45%) with no antiemetic treatment. The difference between groups I and III was significant (p less than 0.05). Comparison of groups II and III and groups I and II showed no statistical significance. Operation time was similar in each group and there was no delay in time of extubation. In each group 1 case of hypotension occurred. No child showed extrapyramidal symptoms. The lower incidence of vomiting in all study groups compared to the literature is thought to be due to three factors: (1) emptying the stomach at the end of the operation by a gastric tube, which is removed before extubation; (2) avoidance of opioids; (3) surgical procedure being done by a very experienced surgeon in 57/61 children (12 vomiting versus 45 not vomiting) in contrast to 3/4 children vomiting postoperatively after surgery by a less experienced surgeon. CONCLUSIONS. We recommend preoperative droperidol 75 micrograms/kg i.v. as the best prophylaxis of postoperative emesis without severe side effects in pediatric strabismus surgery.     

Preoperative oral antiemetics for reducing postoperative vomiting after tonsillectomy in children: granisetron versus perphenazine.

In a prospective, randomized, double-blinded trial, we evaluated the efficacy of two antiemetics given orally, granisetron and perphenazine, for preventing postoperative vomiting after tonsillectomy with or without adenoidectomy in children. One hundred pediatric patients, ASA physical status I, aged 4-10 yr, received either granisetron 40 microg/kg or perphenazine 70 microg/kg (n = 50 each) orally 1 h before surgery. We used a standard general anesthetic technique. The rate of complete response, defined as no emesis and no need for rescue antiemetic medication, during 0-3 h after anesthesia was 86% with granisetron and 60% with perphenazine; the corresponding rate 3-24 h after anesthesia was 86% and 62%, respectively (P < 0.05). No serious adverse events were observed in any of the groups. In conclusion, preoperative oral granisetron is more effective than perphenazine for preventing postoperative vomiting in children undergoing tonsillectomy with or without adenoidectomy. IMPLICATIONS: We compared the efficacy of granisetron and perphenazine given orally for preventing postoperative vomiting after tonsillectomy with or without adenoidectomy in children. Preoperative oral granisetron was more effective than perphenazine.     

Prevention of vomiting after strabismus surgery in children: dexamethasone alone versus dexamethasone plus low-dose ondansetron

BACKGROUND: Postoperative vomiting is a common complication after strabismus surgery. The combination of dexamethasone and ondansetron decreases vomiting after strabismus surgery, while dexamethasone alone decreases vomiting after tonsillectomy in children. We compared the effect of dexamethasone alone to ondansetron plus dexamethasone on postoperative vomiting among children undergoing strabismus surgery. METHODS: Healthy children, aged 2-14 years, who were undergoing strabismus surgery were entered into this randomized, blocked and stratified study. Patients were administered 0.5 mg.kg(-1) midazolam p.o., 20-30 min preoperatively when indicated. The patients had an intravenous induction with 2.5-3.5 mg.kg(-1) propofol or an inhalation induction of anaesthesia with halothane and N2O. All patients were given 20 microg.kg(-1) atropine i.v. Study drugs were administered in a double-blind fashion. Both groups received 150 microg.kg(-1) dexamethasone i.v. Group D patients received placebo and group OD received 50 microg.kg(-1) of ondansetron i.v. Anaesthesia was maintained with halothane and N2O. Postoperative fluid, vomiting and pain management were standardized. Patients were followed for 24 h. We studied 193 patients with 111 patients in the OD group. Demographic data were similar. RESULTS: The overall incidence of vomiting was 23%; in group D and 5%; in group OD (P < 0.001). Each episode of vomiting increased the in-hospital length of stay by 29 min (P < 0.001). CONCLUSIONS: There was a remarkably low incidence of postoperative vomiting of 5%; with the combination of dexamethasone plus a low-dose of ondansetron which more effectively decreased vomiting after strabismus surgery in children when compared with dexamethasone alone.     

Analgesia for circumcision in a paediatric population: comparison of caudal bupivacaine alone with bupivacaine plus two doses of clonidine

BACKGROUND: Clonidine is often used to improve the duration and quality of analgesia produced by caudal epidural blockade, although the optimum dose of clonidine with bupivacaine remains uncertain. Methods: We compared the effect of clonidine, 1 and 2 microg x kg(-1), added to bupivacaine (1.25 mg x kg(-1)) with that of bupivacaine alone in 75 male children undergoing elective circumcision. RESULTS: There was a trend towards increasing duration of analgesia with increasing dose of clonidine [group B (bupivacaine) 280.7 (171.6) min, C1 (bupivacaine + clonidine 1 microg x kg(-1)) 327.8 (188.3) min and C2 (bupivacaine + clonidine 2 microg x kg(-1)) 382.0 (200.6) min], although this difference was not statistically significant. Mean time to arousal from anaesthesia was significantly prolonged with clonidine 2 microg kg(-1) (group C2 21.3 (13-36) min, group C1 14.0 (6-25) min and group B 14.4 (2-32) min. Supplementary analgesic requirements and incidence of adverse effects were low, with no differences between the groups. Conclusions: For paediatric circumcision, under general anaesthesia, the addition of clonidine 2 microg x kg(-1) to low volume (0.5 ml x kg(-1)) caudal anaesthetics has a limited clinical benefit for children undergoing circumcision.     

Does propofol reduce vomiting after strabismus surgery in children?

Background: Previous studies have indicated that propofol anaesthesia may reduce the incidence of postoperative nausea and vomiting after strabismus surgery in children. This study was designed to investigate the incidence of vomiting after strabismus surgery at two different levels of propofol anaesthesia compared to thiopental/isoflurane anaesthesia. Methods: Ninety ASA class I or II children, aged 5–14 yrs were randomly assigned to one of three groups: Group T/I (n=30) induction with 5 mg kg^-1 of thiopental and maintenance with isoflurane, group P5 (n=31) induction with propofol 2 mg kg^-1, maintenance with propofol infusion 5 mg kg^-1 h^-1 or group P10 (n=29) induction with propofol 2 mg kg^-1, maintenance with propofol 10 mg kg^-1 h^_I. All received glycopyrrolate, vecuronium, fentanyl and controlled ventilation with O₂/N₂O 30/ 70. Ketorolac i.v. was given to prevent postoperative pain. If additional analgesia was needed, ibuprofen/acetaminophen or buprenorphine was given according to clinical need. Results: There were no differences between study groups with respect to age, weight, history of previous anaesthesia or emesis after previous anaesthesia, duration of anaesthesia, surgery or sleep after anaesthesia, or number of muscles operated. The incidence of vomiting was 37%, 29% and 28% in groups T/I, P5 and P10, respectively. There were no statistically significant differences between the three groups in the incidence of vomiting. The median age of patients who vomited was 7.5 (range 5.0–13.7) yrs while the median age of the patients who did not vomit was 9.1 (range 5.0–14.0) yrs (P < 0.01). Conclusion: In the present study, propofol anaesthesia compared to thiopental/isoflurane anaesthesia did not reduce the incidence of vomiting following strabismus surgery in children.     

RETRACTED ARTICLE: Granisetron reduces vomiting after strabismus surgery and tonsillectomy in children

Purpose

To evaluate the antiemetic efficacy of granisetron, a selective 5-hydroxytryptamine type 3 receptor antagonist, on postoperative vomiting in children undergoing general anaesthesia for strabismus repair and tonsillectomy with or without adenoidectomy.

Methods

In a randomized, placebo-controlled, double-blind study, fifty patients, 4–10 yr of age, were given a single dose of either placebo (saline, n = 25) or granisetron (40 μg · kg^?1, n = 25) iv over 2–5 min after the induction of anaesthesia and prior to the surgical procedure. Postoperatively, during the first 24 hr after anaesthesia, the frequencies of retching and vomiting were recorded.

Results

There were no differences between the two groups with regard to patient characteristics, surgical procedures and anaesthetic or postoperative management. The incidence of retching was 36% and 12% after administration of placebo or granisetron, respectively (P < 0.05); the corresponding frequencies of vomiting were 32% and 8% (P < 0.05). Four children who had received placebo required another rescue antiemetic drug, whereas none who had received granisetron needed this agent.

Conclusion

Granisetron is effective in the prevention of retching and vomiting after strabismus repair and tonsillectomy in paediatric patients.     

A double-blind comparison of intravenous ondansetron and placebo for preventing postoperative emesis in 1- to 24-month-old pediatric patients after surgery under general anesthesia

We assessed the efficacy and safety of ondansetron (0.1 mg/kg IV) prophylactically administered before surgery for prevention of postoperative vomiting (POV) in a double-blind, placebo-controlled study of 670 pediatric patients, 1- to 24-mo-old, undergoing elective surgery under general anesthesia. The study enrolled 335 children in each treatment group (ondansetron versus placebo). Significantly fewer children treated with ondansetron exhibited emesis or discontinued the study prematurely after surgery (ondansetron, 11%; placebo, 28%; odds ratio = 0.33; P < 0.0001). The number required to treat prophylactically with ondansetron to prevent POV was approximately six. Ondansetron treatment also resulted in fewer patients requiring rescue medication or assumed to have had rescue upon early discontinuation from the study during the postoperative period (ondansetron, 5%; placebo, 10%) and less emesis (0 of 6) after rescue medication when compared with placebo (7 of 21). The incidence of POV and other antiemetic effects of ondansetron were similar in children aged 1-12 mo and 13-24 mo and in children prospectively expected or not expected to require opioids as part of their anesthetic or analgesic management. Ondansetron was well tolerated; the incidence of adverse events considered possibly related to study drug was similar between treatment groups (ondansetron, 1.8%; placebo, 1.5%). IMPLICATIONS: This prospective, randomized, double-blind, placebo-controlled study establishes the efficacy and tolerability of IV ondansetron (0.1 mg/kg) in the prevention of postoperative emesis in 1- to 24-mo-old pediatric patients undergoing elective surgery under general anesthesia.     

Prophylactic therapy with granisetron in the prevention of vomiting after paediatric surgery. A randomized, double-blind comparison with droperidol and metoclopramide

The antiemetic efficacy of droperidol, metoclopramide and granisetron was compared with placebo in the reduction of vomiting after paediatric surgery (the extremities; inguinal hernia; and phimosis) during general inhalational anaesthesia. One hundred children, ASA physical status I, 4–10 years of age, were enrolled in a prospectively, randomized, double-blind investigation and assigned to one of four treatment regimens: placebo (saline, n=25), droperidol (50 μg·kg¹, n=25), metoclopramide (0.25 mg·kg-¹, n=25) or granisetron (40 μg·kg^-1, n=25). These drugs were administered intravenously (iv) after inhalation induction of anaesthesia. A complete response, defined as no emesis and no need for another rescue antiemetic during the first 24 h after anaesthesia, occurred in 60%, 76%, 68% and 88% of patients who had received placebo, droperidol, metoclopramide and granisetron, respectively (P<0.05; overall Fisher's exact probability test). The incidence of adverse events postoperatively was not different among the treatment groups. In conclusion, granisetron 40 μg·kg^-1 is a better antiemetic than droperidol and metoclopramide when compared to placebo for the prevention of postoperative emesis in children.     

Dolasetron for the prevention of postoperative vomiting in children undergoing strabismus surgery

BACKGROUND: Children undergoing strabismus surgery have a high incidence of postoperative vomiting (POV). The purpose of this study was to assess the efficacy and safety of dolasetron for the prevention of emesis comparing a single 0.35 mg.kg-1 or 12.5 mg dose with placebo. METHODS: Children aged 2-12 years with an ASA status of 1 or 2 undergoing strabismus surgery were randomized in a double-blind manner to one of three treatment groups. Patients were excluded with a history of previous postoperative vomiting or motion sickness, allergy to serotonin receptor antagonists or previous antiemetic administration within 24 h prior to enrollment. General anaesthesia was induced with sevoflurane and N2O/O2 and maintained with isoflurane and N2O/O2. The study medication was administered 15 min prior to the end of surgery. Patients experiencing two or more episodes of vomiting were rescued in the postanaesthesia care unit (PACU) with metoclopramide 0.15 mg.kg-1. A total of 118 patients were enrolled with documentation of the number and severity of vomiting episodes, time to awakening, PACU length of stay and postoperative agitation. RESULTS: Patients with an acute complete response (ACR), defined as no emetic episodes and no rescue medication within 24 h of study drug administration were 62% (weight dose), 64% (fixed dose) and 33% (placebo, P < 0.05). CONCLUSIONS: There was no statistical difference between the 0.35 mg.kg-1 dose and the fixed 12.5 mg dose of dolasetron with both reducing the incidence of POV.     

Postoperative emesis after pediatric strabismus surgery: the effect of dixyrazine compared to droperidol

Sixty-one children, ASA physical status I, aged 2-14 years, admitted for strabismus surgery were studied. All were premedicated with diazepam and atropin rectally. Anesthesia was induced with thiopental or with halothane on a facemask, and succinylcholine was given to facilitate tracheal intubation. Anesthesia was maintained with halothane and nitrous oxide. Each child was randomly assigned to receive either no antiemetic prophylaxis (control), droperidol 0.075 mg/kg, or dixyrazine 0.25 mg/kg. The drugs were injected intravenously at the end of surgery. The incidence of vomiting during the following 24 h was 65% in the control group, 48% in the droperidol group, and 25% in the dixyrazine group (P less than 0.05 as compared to the control group). Four hours after the operation, six children in the droperidol group and none in the dixyrazine group (P less than 0.05) were difficult to arouse. It is concluded that dixyrazine reduces the incidence of postoperative vomiting without causing heavy sedation.     

The antiemetic effect of lorazepam after outpatient strabismus surgery in children.

The high incidence of postoperative emesis after strabismus surgery in pediatric outpatients can be reduced by the prophylactic administration of droperidol 75 micrograms/kg intravenously. However, this may be associated with profound sedation, delayed discharge, dysphoria, agitation, and extrapyramidal symptoms in this population. Because lorazepam used as an antiemetic in children during chemotherapy decreased the incidence of nausea and vomiting, we compared the antiemetic effects of lorazepam and droperidol in a randomized, double-blind, placebo-controlled study of 129 healthy children undergoing surgical correction of strabismus. The children, aged 1-13 yr, were randomly allocated into three groups. The children in group 1 received droperidol 75 micrograms/kg intravenously; those in group 2 received lorazepam 10 micrograms/kg intravenously; and those in group 3 received placebo. Anesthesia consisted of halothane, nitrous oxide in oxygen, and atracurium. Study drugs were administered intravenously after induction of anesthesia but before surgery. In children 3-13 yr old, administration of either lorazepam or droperidol was associated with a lower (P < 0.024) incidence of postoperative vomiting. There was no difference between the antiemetic effect of lorazepam and that of droperidol. The incidence of postoperative agitation was greater in the droperidol group (P < 0.001) than in the lorazepam and placebo groups. Postdischarge vomiting was less (P < 0.009) in children younger than 3 yr of age. Lorazepam, similar to droperidol, has an antiemetic effect in outpatient children 3-13 yr old undergoing strabismus correction, but it is associated with less postoperative agitation than is droperidol.