Prophylactic antiemetic treatment with ondansetron in children undergoing tonsillectomy

Population Pharmacokinetics of Metoclopramide in Infants, Children, and Adolescents

Metoclopramide is commonly used for gastroesophageal reflux. The aims of the present study were to develop a pediatric population pharmacokinetic (PopPK) model, which was applied to simulate the metoclopramide exposure following dosing used in clinical practice. Opportunistic pharmacokinetic data were collected from pediatric patients receiving enteral or parenteral metoclopramide per standard of care and these data were simultaneously fitted using NONMEM. Allometric scaling with body weight was included a priori in the model. Using the final model, the steady‐state maximum concentrations (C_ss,max) and the area under the metoclopramide plasma concentration‐time curve at steady state from 0 to 6 hours (AUC_ss,0–6h) were simulated following 0.1 or 0.15 mg/kg orally every 6 hours in virtual patients, and compared with previously reported ranges associated with toxicity or the efficacy for gastroesophageal reflux in infants. A two‐compartment model with first‐order absorption best characterized 87 concentration measurements from 50 patients (median [range] postnatal age of 8.89 years [0.01–19.13]). There were 20 infants (≤ 2 years), 9 children (2 years to age ≤ 12 years), and 21 adolescents (> 12 years). Body weight was the only covariate included in the final model. For > 75% of virtual patients, simulated C_ss,max and AUC_ss,0–6h estimates were within the range associated with efficacy for gastroesophageal reflux in infants; however, slightly lower exposures were predicted in virtual patients < 2 years. Our study suggests that a metoclopramide enteral dose of 0.1 mg/kg every 6 hours, which was previously recommended for pediatric patients, results in simulated exposure generally within suggested ranges for the treatment of gastroesophageal reflux.

A review of dexamethasone as an adjunct to adenotonsillectomy in the pediatric population

Although one of the most commonly performed surgical procedures in children and frequently performed as outpatient surgery, the postoperative course following tonsillectomy may include nausea, vomiting, poor oral intake, and pain. These problems may last days into the postoperative course. Although opioids may be used to treat the pain, comorbid conditions such as obstructive sleep apnea may mandate limiting the dose and the frequency of administration. Adjunctive agents may improve the overall postoperative course of patients and limit the need for opioid analgesics. Dexamethasone is a frequently administered intraoperatively as an adjunctive agent to decrease inflammation and pain, limit the potential for postoperative nausea and vomiting, and improve the overall postoperative course. The following manuscript reviews the use of dexamethasone to improve outcomes following tonsillectomy or adenotonsillectomy, discusses the controversies regarding its potential association with perioperative bleeding, and investigates options for dosing regimens which may maintain the beneficial physiologic effects while limiting the potential for bleeding.

Randomized trial of acupuncture with antiemetics for reducing postoperative nausea in children

BACKGROUND

Postoperative nausea and vomiting (PONV) is common after tonsillectomy in children. There is evidence that perioperative acupuncture at the pericardium 6 (P6) point is effective for preventing PONV in adults. Our goal was to determine if intraoperative acupuncture at the P6 point, in addition to usual antiemetics, is more effective than antiemetics alone in preventing PONV in children.

METHODS

In a randomized double-blind trial, 161 children age 3 through 9 years undergoing tonsillectomy with or without adenoidectomy were randomized to either bilateral acupuncture at P6 plus antiemetics (n = 86) or antiemetics only (n = 75). All participants received ondansetron 0.15 mg/kg and dexamethasone 0.25 mg/kg, up to 10 mg. The presence of nausea, retching, emesis and administration of additional antiemetics were recorded during phases I and II of PACU recovery. Follow-up calls occurred on postoperative day 1 (POD 1).

RESULT

During phase I and II recovery, the incidence of PONV was significantly less with acupuncture than without (7.0% vs 34.7%, RR: 0.2, 95% CI: 0.09-0.46; P < 0.001). The difference in PONV was driven by less nausea in the acupuncture group (5.0% vs 24.0%), with no difference in vomiting between the two groups. In the first 24 hours, PONV occurred in 36.1% with acupuncture and 49.3% without; these values did not differ significantly (P = 0.09).

CONCLUSIONS

Children receiving acupuncture plus antiemetic therapy had less risk of developing nausea during phase I and II recovery, but there was no difference in PONV on POD 1. Acupuncture may reduce nausea in the PACU, even when combined with antiemetics.

More Harm Than Benefit of Perioperative Dexamethasone on Recovery Following Reconstructive Head and Neck Cancer Surgery: A Prospective Double-Blind Randomized Trial

PURPOSE

Prospective studies on the effect of dexamethasone after microvascular reconstructive head and neck surgery are sparse despite the widespread use of dexamethasone in this setting. The aim of this study was to clarify whether perioperative use of dexamethasone would improve the quality and speed of recovery. The authors hypothesized that dexamethasone would enhance recovery and diminish pain and nausea.

MATERIALS AND METHODS

Ninety-three patients with oropharyngeal cancer and microvascular reconstruction were included in this prospective double-blinded randomized controlled trial. Patients in the study group (n = 51) received dexamethasone 60 mg over 3 perioperative days; 42 patients did not receive dexamethasone and served as controls. Patient rehabilitation, postoperative opioid and insulin consumption, postoperative nausea and vomiting (PONV), and C-reactive protein (CRP), leukocyte, and lactate levels were recorded.

RESULTS

There was significantly less pain in the study group (P = .030) and the total oxycodone dose for 5 days postoperatively was lower (P = .040). Dexamethasone did not significantly lessen PONV for 5 days postoperatively (P > .05). There were no differences between groups in intensive care unit or hospital stay or in other clinical measures of recovery. Patients receiving dexamethasone required significantly more insulin compared with patients in the control group (P < .001). Lactate and leukocyte levels were significantly higher (P < .001) and CRP levels were significantly lower in the study group.

CONCLUSION

The only benefit of perioperative dexamethasone use was lower total oxycodone dose; however, the disadvantages were greater. Because dexamethasone can have adverse effects on the postoperative course, routine use of dexamethasone as a pain or nausea medication during reconstructive head and neck cancer surgery is not recommended.

The Safety of Metoclopramide in Children: A Systematic Review and Meta-Analysis

INTRODUCTION

Metoclopramide is recommended for adults with breakthrough or refractory chemotherapy-induced nausea and vomiting (CINV) and for CINV prophylaxis in children. The drug regulatory agencies of Canada and the EU have revised the labelling of metoclopramide to contraindicate its use in children aged <1 year and to caution against its use in children aged <5 years and its duration of use beyond 5 days.

OBJECTIVE

This review describes the safety of metoclopramide in children when given for any indication.

METHODS

We conducted electronic searches in MEDLINE and Embase as of 9 March 2015. All studies in English reporting adverse effects associated with the use of metoclopramide in children (aged ≤18 years) were included. Adverse effects that had a cumulative incidence of at least 1 % and were reported in prospective studies were synthesized.

RESULTS

A total of 108 (57 prospective) studies involving 2699 patients (2745 metoclopramide courses) were included. The most common adverse effects reported in prospective studies of metoclopramide in children were extrapyramidal symptoms (EPS; 9 %, 95 % confidence interval [CI] 5-17), diarrhea (6 %, 95 % CI 4-9), and sedation (multiple-dose studies: 6 %, 95 % CI 3-12). Dysrhythmia, respiratory distress/arrest, neuroleptic malignant syndrome, and tardive dyskinesia were rarely associated with metoclopramide use.

LIMITATIONS

The definitions of adverse effects reported in the included studies were heterogeneous, and the risk of bias in most studies was moderate.

CONCLUSIONS

The most commonly reported adverse effects associated with the use of metoclopramide in children-EPS, diarrhea, and sedation-were reversible and of no long-term significance. Adverse effects that were life threatening or slow to resolve were rarely associated with its use in children.

WITHDRAWN: Drugs for preventing postoperative nausea and vomiting

BACKGROUND

Drugs can prevent postoperative nausea and vomiting, but their relative efficacies and side effects have not been compared within one systematic review.

OBJECTIVES

The objective of this review was to assess the prevention of postoperative nausea and vomiting by drugs and the development of any side effects.

SEARCH METHODS

We searched The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2, 2004), MEDLINE (January 1966 to May 2004), EMBASE (January 1985 to May 2004), CINAHL (1982 to May 2004), AMED (1985 to May 2004), SIGLE (to May 2004), ISI WOS (to May 2004), LILAC (to May 2004) and INGENTA bibliographies.

SELECTION CRITERIA

We included randomized controlled trials that compared a drug with placebo or another drug, or compared doses or timing of administration, that reported postoperative nausea or vomiting as an outcome.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted outcome data.

MAIN RESULTS

We included 737 studies involving 103,237 people. Compared to placebo, eight drugs prevented postoperative nausea and vomiting: droperidol, metoclopramide, ondansetron, tropisetron, dolasetron, dexamethasone, cyclizine and granisetron. Publication bias makes evidence for differences among these drugs unreliable. The relative risks (RR) versus placebo varied between 0.60 and 0.80, depending upon the drug and outcome. Evidence for side effects was sparse: droperidol was sedative (RR 1.32) and headache was more common after ondansetron (RR 1.16).

AUTHORS' CONCLUSIONS

Either nausea or vomiting is reported to affect, at most, 80 out of 100 people after surgery. If all 100 of these people are given one of the listed drugs, about 28 would benefit and 72 would not. Nausea and vomiting are usually less common and, therefore, drugs are less useful. For 100 people, of whom 30 would vomit or feel sick after surgery if given placebo, 10 people would benefit from a drug and 90 would not. Between one to five patients out of every 100 people may experience a mild side effect, such as sedation or headache, when given an antiemetic drug. Collaborative research should focus on determining whether antiemetic drugs cause more severe, probably rare, side effects. Further comparison of the antiemetic effect of one drug versus another is not a research priority.

Adjuncts to local anaesthetics in tonsillectomy: a systematic review and meta-analysis

The infiltration of local anaesthetic agents has been shown to reduce post-tonsillectomy pain. A number of recent studies have shown that the addition of agents such as clonidine and dexamethasone improve the efficacy of nerve blocks and spinal anaesthesia. The aim of this review was to determine whether additives to local anaesthetic agents improve post-tonsillectomy outcomes. Four major databases were systematically searched for all relevant studies published up to August 2016. All study designs with a control group receiving local anaesthetic infiltration and an intervention receiving the same infiltration with an added agent were included in this review. These studies were then assessed for level of evidence and risk of bias. The data were then analysed both qualitatively and where appropriate by meta-analysis. We reviewed 11 randomised controlled trial (RCTs) that included 854 patients. Due to inconsistencies in the methods used to report outcomes, both quantitative and qualitative comparisons were required to analyse the extracted data. Overall, we found that dexamethasone, magnesium, pethidine and tramadol reduce post-operative pain and analgesia use, with dexamethasone in particular significantly reducing post-operative nausea and vomiting and magnesium infiltration significantly reducing the incidence of laryngospasm. This systematic review of RCTs provides strong evidence that the use of dexamethasone and magnesium as additives to local anaesthetics reduces post-tonsillectomy pain and analgesia requirement. There is limited evidence that pethidine and tramadol have a similar effect on pain and analgesia requirement. The studies in this pooled analysis are sufficiently strong to make a level one recommendation that the addition of magnesium to local anaesthetics reduces the incidence of laryngospasm, a potentially lethal post-operative complication. Review level of evidence: 1.

Acupuncture as an Antiemetic in Children who Underwent Adenoidectomy and/or Tonsillectomy

OBJECTIVE

Postoperative vomiting (POV) is one of the most common problems following general anaesthesia, and many factors, either solely or in combination, may play a role in aetiology. Acupuncture is a technique that the World Health Organization has accepted as a complementary treatment. This study presents our experience with acupuncture for POV treatment in a study of paediatric tonsillectomy cases.

METHODS

The study included ASA I-II patients (n=70) aged 2-14 years who underwent tonsillectomy and/or adenoidectomy under general anaesthesia. The patients were randomly divided into the following two groups: control and study group. In the study group, an acupuncture needle was intraoperatively applied to the P6 acupuncture point for 20 min. Antiemetics were not administered to either group because of the standard applications in the preoperative period. The patients were postoperatively evaluated by nurses who were unaware about the techniques used in either group.

RESULTS

No statistically significant difference was determined between the groups with regard to age, sex, nature of the operation, duration of anaesthesia, duration of the operation, surgical method and ASA scores. A statistically significant difference was determined between the groups with respect to vomiting rates. The acupuncture group presented with 0.28-times fewer vomiting episodes than the control group.

CONCLUSION

The results of the study demonstrate that acupuncture has an apparent antiemetic efficacy in POV. Its routine use for POV may improve postoperative comfort and reduce drug use for prophylactic or therapeutic purposes.

Comparison between dexmedetomidine and remifentanil infusion in emergence agitation during recovery after nasal surgery: A randomized double-blind trial

BACKGROUND

Postoperative emergency agitation (EA) is a common problem. Dexmedetomidine and remifentanil may be used to prevent this problem. Our primary aim was to compare dexmedetomidine, remifentanil, and placebo with respect to their effectiveness in preventing postoperative EA.

MATERIAL AND METHODS

Ninety patients undergoing nasal surgery were randomized into three groups. The dexmedetomidine group (group D, n = 30) received dexmedetomidine infusion at a rate of 0.4 μg kg(-1 ) h(-1); the remifentanil group (group R, n = 30) received remifentanil infusion at a rate of 0.05 μg kg(-1) min(-1) from induction of anesthesia until extubation; and the control group (group S, n = 30) received a volume-matched normal saline infusion as a placebo. Propofol (1.5-2 mg kg(-1)) and fentanyl (1 μg kg(-1)) were used to initiate anesthesia, and desflurane was used to maintain anesthesia. The incidence of agitation, hemodynamic parameters, and recovery characteristics were evaluated during emergence.

RESULTS

The incidence of EA was significantly higher in group S (46.7%) compared with groups R and D (3.3 and 20%, respectively; p < 0.001). The lowest incidence of EA was detected in group R (p = 0.046). Residual sedation in the post-anesthesia care unit (PACU) was similar in all groups (p = 0.947). The incidence of nausea or vomiting was significantly lower in group D than in groups R and S (p = 0.043). Administration of analgesics in the PACU was higher in group R than in groups S and D (p = 0.015).

CONCLUSION

Anesthetic maintenance with either remifentanil or dexmedetomidine infusion until extubation provided a more smooth and hemodynamically stable emergence, without complications after nasal surgery. While remifentanil was superior to dexmedetomidine with regard to avoiding EA, dexmedetomidine was more effective than remifentanil regarding vomiting and pain.

Cost-effectiveness of intravenous acetaminophen for pediatric tonsillectomy

OBJECTIVE

The primary outcome of this study was to examine the cost-effectiveness of the intraoperative combination of intravenous (IV) acetaminophen and IV opioids, versus IV opioids alone, as a part of an inhalational anesthetic technique for tonsillectomy in children.

METHODS

We used Decision Maker® software to construct and analyze a decision analytic model. Base-case and sensitivity analyses were performed. We studied the use of rescue analgesics in the postanesthesia care unit (PACU), adverse effects of acetaminophen and opioids, and costs associated with adverse effects. Costs were in 2013 US dollars, and effectiveness was measured as frequency of avoiding the need for rescue analgesics. Direct medical costs included medication, equipment, supplies, and labor associated with the treatment of adverse events from pain medications. Medication costs assumed single-dose vials.

RESULTS

In the base case, IV acetaminophen in combination with opioids was both less costly ($17.12) and more effective (3.3% fewer rescue events). In sensitivity analyses, the combination strategy remained cost-effective as long as the frequency of rescue analgesic administration was less than that in the opioid-alone strategy. Although medication costs of the combination strategy were higher, the overall costs were less than the competing strategy due to reduced adverse effects and reduced time spent in PACU.

CONCLUSIONS

The routine use of IV acetaminophen as an adjuvant to IV opioids for tonsillectomy with or without adenoidectomy in children aged <17 years should be considered as a means to reduce the need for rescue analgesia and in turn reduce costs.

Gastric Decompression Decreases Postoperative Nausea and Vomiting in ENT Surgery

There is a passive blood flow to the stomach during oral and nasal surgery. It may cause postoperative nausea and vomiting (PONV). We researched the relationship between gastric decompression (GD) and severity of PONV in ear, nose, and throat (ENT) surgery. 137 patients who have been into ENT surgery were included in the study. In Group I (n = 70), patients received GD after surgery before extubation; patients in Group II (n = 67) did not receive GD. In postoperative 2nd, 4th, 8th, and 12th hours, the number and ratio of patients demonstrating PONV were detected to be significantly more in Group II as compared to Group I. PONV was also significantly more severe in Group II as compared to Group I. In Group I, the PONV ratio in the 2nd hour was significantly more for those whose amounts of stomach content aspired were more than 10 mL as compared to those whose stomach content aspired was less than 10 mL. In the 4th, 8th, and 24th hours, there is no statistically significant difference between the stomach content aspired and PONV ratio. GD reduces the incidence and severity of PONV in ENT surgery.

Is fasting duration important in post adenotonsillectomy feeding time?

Background:

Adenotonsillectomy is a common otolaryngology surgery. Nausea and vomiting are the most common complications of this procedure with a prevalence ranging from 49% to 73 %.

Objectives:

Our aim was to evaluate the effects of short time fasting protocol on decreasing postoperative pain, nausea and vomiting, and initiation of oral feeding after adenotonsillectomy.

Patients and Methods:

120 children aged 4 to 14 years candidates for adenotonsillectomy were randomly divided into intervention and control groups (n = 120, 60 in each group). Each patient of the intervention group was given oral dextrose 10% as much volume as he could consume at 3 and 6 hours prior to the operation. All the data including pain severity, nausea and vomiting of the patients, the time of oral feeding initiation etc. were gathered in checklists after the operation. Statistical analyses were then performed using Statistical Package for the Social Sciences (SPSS) software version 16. Descriptive statistical methods and mean difference test for independent groups and chi square test or Fisher exact test, and if regression needed model test were applied. A P value of 0.05 or less was considered statistically significant.

Results:

The amount of Acetaminophen administered for the intervention group was significantly lower than the control group, and also the time of oral feeding initiation was significantly shorter in the intervention group than the control group (P < 0.005). Pain severity at all occasions following surgery was significantly lower in the intervention group than the control group (P < 0.001). Although frequency of nausea at recovery time was significantly lower in the intervention group than the control group (P < 0.002), there were no significant differences in frequency of nausea between the two groups at other postoperative occasions. Postoperative vomiting frequency was not significant between the two groups at any occasions.

Conclusions:

The findings of this survey showed that shortening the duration of pre-adenotonsillectomy fasting period and hydration of patients several hours prior to the operation might be effective in decreasing postoperative pain and facilitating postoperative oral feeding initiation. Nevertheless this method does not seem to prevent postoperative nausea and vomiting.

Prevention of sevoflurane related emergence agitation in children undergoing adenotonsillectomy: A comparison of dexmedetomidine and propofol

Background:

Emergence agitation (EA) in children is increased after sevoflurane anesthesia. Propofol and dexmedetomidine have been used for prophylactic treatment with controversial results. The aim of the present study was to compare the effect of a single dose of propofol or dexmedetomidine prior to termination of sevoflurane-based anesthesia on the incidence and severity of EA in children.

Methods:

One hundred and twenty children, American Society of Anesthesiologists I-II, 2-6 years old undergoing adenotonsillectomy under sevoflurane based anesthesia were enrolled in the study. Children were randomly allocated to one of the three equal groups: (Group C) received 10 ml saline 0.9%, (Group P) received propofol 1 mg/kg or (group D) received dexmedetomidine 0.3 ug/kg^-1. The study drugs were administered 5 min before the end of surgery. In post anesthesia care unit (PACU), the incidence of EA was assessed with Aonos four point scale and the severity of EA was assessed with pediatric anesthesia emergence delirium scale upon admission (T0), after 5 min (T5), 15 min (T15) and 30 min (T30). Extubation time, emergence time, duration of PACU stay and pain were assessed.

Results:

The incidence and severity of EA were lower in group P and group D compared to group C at T0, T5 and T15. The incidence and severity of EA in group P were significantly higher than group D at the same times. The incidence and severity of EA decreased significantly over time in all groups. The modified Children's Hospital of Eastern Ontario Pain Scale was significantly lower in group D compared to group C and group P.

Conclusions:

Dexmedetomidine 0.3 ug/kg¹ was more effective than propofol 1 mg/kg in decreasing the incidence and severity of EA, when administered 5 min before the end of surgery in children undergoing adenotonsillectomy under sevoflurane anesthesia.

Effect of systemic steroids on post-tonsillectomy bleeding and reinterventions: systematic review and meta-analysis of randomised controlled trials

OBJECTIVE

To evaluate the risk of postoperative bleeding and reintervention with the use of systemic steroids in patients undergoing tonsillectomy.

DESIGN

Systematic review and meta-analysis of randomised controlled trials.

DATA SOURCES

Medline, Embase, Cochrane Library, Scopus, Web of Science, Intute, Biosis, OpenSIGLE, National Technical Information Service, and Google Scholar were searched. References from reviews identified in the search and from included studies were scanned.

REVIEW METHODS

Randomised controlled trials comparing the administration of systemic steroids during tonsillectomy with any other comparator were eligible. Primary outcome was postoperative bleeding. Secondary outcomes were the rate of admission for a bleeding episode, reintervention for a bleeding episode, blood transfusion, and mortality.

RESULTS

Of 1387 citations identified, 29 randomised controlled trials (n=2674) met all eligibility criteria. Seven studies presented a low risk of bias, but none was specifically designed to systematically identify postoperative bleeding. Administration of systemic steroids did not significantly increase the incidence of post-tonsillectomy bleeding (29 studies, n=2674 patients, odds ratio 0.96 (95% confidence interval 0.66 to 1.40), I&sup2;=0%). We observed a significant increase in the incidence of operative reinterventions for bleeding episodes in patients who received systemic steroids (12, n=1178, 2.27 (1.03 to 4.99), I&sup2;=0%). No deaths were reported. Sensitivity analyses were consistent with the findings.

CONCLUSIONS

Although systemic steroids do not appear to increase bleeding events after tonsillectomy, their use is associated with a raised incidence of operative reinterventions for bleeding episodes, which may be related to increased severity of bleeding events. Systemic steroids should be used with caution, and the risks and benefits weighed, for the prevention of postoperative nausea and vomiting after tonsillectomy before further research is performed to clarify their condition of use.

Use of intravenous steroids at induction of anesthesia for septoplasty to reduce post-operative nausea and vomiting and pain: a double-blind randomized controlled trial

To determine the effectiveness of dexamethasone to reduce pain, nausea and vomiting after septoplasty. Study is a prospective double-blind randomized controlled trial. A total of 90 patients were enrolled and received an either of dexamethasone or placebo in the induction of anesthesia. The patients were asked to note the level of pain on the visual analogue scale in the first 24 h after surgery. They also had to record their severity of nausea and number of vomiting attacks. There were statistically significant differences between the two groups for the level of pain noted on the visual analogue scale. The severity of nausea was lower after treatment with dexamethasone but the difference between two groups was not significant. There was also a significant decrease in the number of vomiting attacks in patients treated with dexamethasone. A single dose of 8 mg of dexamethasone, given intravenously, at induction of anesthesia for septoplasty significantly decreased the pain, post-operative nausea and vomiting for the day of operation.

Ondansetron does not Modify Emergence Agitation in Children

In this prospective, placebo-controlled study, we evaluated the effect of prophylactic ondansetron therapy on emergence agitation of children who underwent minor surgery below the umbilicus. Seventy children aged one to six years and American Society of Anesthesiologists physical status I were studied. Children were premedicated with midazolam rectally and were randomly assigned to receive either ondansetron (Group O) or placebo (Group P) in combination with caudal anaesthesia. Children in Group O received intravenous ondansetron (0.1 mg/kg for children weighing <40 kg, 4 mg for children weighing >40 kg) and Group P (n=35) received normal saline 2 ml following anaesthesia induction with sevoflurane. Airway management was provided with LMA-Proseal without muscle relaxation and anaesthesia maintenance was provided with a 60:40 N2O:O2 mixture and sevoflurane. Emergence agitation was evaluated with a ten point scale and pain level was assessed every 10 minutes for the first 30 minutes after admission to the recovery room.

There were no significant differences between the placebo and ondansetron groups with respect to demographic, anaesthetic and surgical details. Incidences of emergence agitation in ondansetron and placebo groups were similar (32.4% and 30.3% at 10 minutes respectively). Mean modified Children's Hospital of Eastern Ontario pain scale scores and mean ten-point scale scores and emergence agitation incidences decreased similarly after 10 minutes in both groups. Ready time for discharge was similar between the groups. Agitated patients had significantly increased ready time for discharge compared to non-agitated patients (P=0.001).

Prophylactic intravenous ondansetron administration does not reduce emergence agitation comparing to placebo after sevoflurane anaesthesia.

Reinforced laryngeal mask airway compared with endotracheal tube for adenotonsillectomies

BACKGROUND

The endotracheal tube (ETT) has traditionally been considered the best airway device during adenotonsillectomy because a well protected and secured airway is provided. This has been challenged by the introduction of the reinforced laryngeal mask airway (RLMA). It does not kink, is less traumatic during insertion and better tolerated during emergence. The purpose of this study was to compare the use of the RLMA with ETT with regards to postoperative pain, nausea, vomiting and perioperative efficacy in a series of children due for adenotonsillectomy.

METHODS

One hundred and thirty-four children, aged 3-16 years and scheduled for ambulatory adenotonsillectomies, were randomly assigned to two groups where the airways were secured with either the ETT (n = 62) or the RLMA (n = 69). We registered the incidence of peroperative and postoperative anaesthesiological complications and time consume, in addition to postoperative pain, nausea and overall satisfaction.

RESULTS

The Group RLMA scored significantly lower for maximal pain during the first 4 h postoperatively (P = 0.015). There were no significant differences in pain scores at 24 h or rescue pain medication postoperatively. The Group RLMA spent mean 4.2 min less in the operating room after surgery (P = 0.001). There were no significant differences in postoperative nausea. In those patients finally treated with ETT, including five conversions from RLMA, significantly more patients (10 vs. 2) had airway irritations (P < 0.02).

CONCLUSION

The RLMA, when feasible, is a well tolerated and effective alternative to the ETT for use during adenotonsillectomies in children, with beneficial effects on airway irritations, operating room efficiency and early postoperative pain.

Nausea and vomiting after ENT surgeries: A comparison between ondansetron, metoclopramide and small dose of propofol

AIMS

To evaluate the antiemetic efficacy of ondansetron, metoclopramide or small dose of propofol following ear, nose and throat (ENT) surgery.

MATERIALS AND METHODS

A prospective randomized study involving 60 patients, both children and adults undergoing elective ENT surgery under standard general anesthesia. At the completion of surgery the patients received either 0.1 mg/kg of ondansetron or 0.2 mg/kg of metoclopramide or 0.5 mg/kg of propofol intravenously. The patients were observed for 24 hrs after operation for any occurrence of nausea and vomiting.

RESULTS

The incidence of postoperative nausea and vomiting (PONV) during first 24 hrs was recorded in 20%, 70%, 50% of patients who had received ondansetron, metoclopr-amide or propofol respectively (p < 0.05). Fewer patients given ondansetron needed rescue antiemetic. The incidence of PONV was higher following middle year surgery.

CONCLUSION

It was concluded that ondansetron was most effective in preventing occurrence of PONV while metoclopramide was least effective. Propofol was effective only in 50% of patients, thus not recommended for routine use.

Randomized, double-blind study comparing the efficacy of moderate-dose metoclopramide and ondansetron for the prophylactic control of postoperative vomiting in children after tonsillectomy

BACKGROUND

Postoperative vomiting (POV) is a major cause of morbidity after tonsillectomy in children. It has been well established that anti-serotinergic agents are effective for the prophylactic control of POV in this patient group. It has been suggested that at moderate doses (0.5 mg kg(-1)), metoclopramide is also an effective agent. No study has been performed comparing the efficacy of an anti-serotinergic agent and moderate-dose metoclopramide.

METHODS

A total of 557 children undergoing tonsillectomy with or without adenoidectomy were randomly allocated to receive either ondansetron 0.1 mg kg(-1) or metoclopramide 0.5 mg kg(-1). All received a standardized muscle-relaxant anaesthetic and dexamethasone 0.1 mg kg(-1). The primary outcome was any vomit in the immediate postoperative period. Comparisons were made of the proportion in each group reaching the primary outcome and the time until their first vomit. The study was designed to detect equivalence.

RESULTS

The incidence of vomiting in the group receiving ondansetron (25.3%) was 12% lower (95% CI 4.4-19.7) than those in metoclopramide (37.3%). The time until first vomit was significantly longer in the group receiving ondansetron (hazard ratio 0.61, 95% CI 0.45-0.82).

CONCLUSIONS

Although the incidence of vomiting was similar, when these results are compared with a pre-specified zone of equivalence of 0-15%, it cannot be concluded that the effect of metoclopramide is equivalent to ondansetron. Survival analysis indicated that those in the metoclopramide group vomited substantially earlier. It is concluded, therefore, that ondansetron 0.1 mg kg(-1) is a superior drug to metoclopramide 0.5 mg kg(-1) for the prophylactic control of POV in children undergoing tonsillectomy.

Prevention of postoperative nausea and vomiting in children following adenotonsillectomy, using tropisetron with or without low-dose dexamethasone

PURPOSE

Postoperative nausea and vomiting (PONV) after adenotonsillectomy in children is, in spite of the prophylactic administration of tropisetron, still a frequent event. The aim of this study was to evaluate the benefit of the additional systemic administration of low-dose dexamethasone (0.15 mg x kg(-1)) for the prevention of PONV.

METHODS

With hospital ethics committee approval, we investigated children undergoing adenotonsillectomy receiving tropisetron (0.1 mg x kg(-1); maximum dose, 2 mg) or tropisetron (0.1 mg x kg(-1); maximum dose, 2 mg) plus dexamethasone (0.15 mg x kg(-1); maximum dose, 6 mg) intraoperatively. The incidence of vomiting episodes and the need for postoperative analgesics were recorded. Patient data were analyzed using the t-test and the chi(2) test (significance level of P = 0.05). Data values are means +/- SD.

RESULTS

Ninety children (39 girls and 51 boys), aged 5.6 +/- 2.8 years and weighing 21.9 +/- 8.8 kg, were enrolled in the study. The overall incidence of vomiting was 38.9% within the first 24 h (67 vomiting events) and 44.4% within 48 h postoperatively (87 vomiting events). The incidence of vomiting in the tropisetron-only group was 53.3% (24/45) at 24 h and 60% (27/45) at 48 h (24 h: P < 0.001 and 48 h: P = 0.04) and 24.4% (11/45) at 24 h and 28.9% (13/45) at 48 h in the tropisetron-dexamethasone group. The need for postoperative nalbuphine was double in patients treated with tropisetron-dexamethasone (0.61 mg +/- 0.36 mg x kg(-1) x 48 h(-1)) compared to that in patients receiving only tropisetron (0.31 mg +/- 0.28 mg x kg(-1) x 48 h(-1); P < 0.0001).

CONCLUSION

A low-dose bolus of dexamethasone (0.15 mg x kg(-1)) in combination with tropisetron, compared to tropisetron alone, considerably reduced the incidence of vomiting in children following pediatric adenotonsillectomy.

Management of postoperative nausea and vomiting in children

Postoperative nausea and vomiting (PONV) continues to be a frequent and important cause of morbidity in children. Postoperative vomiting (POV) is more commonly studied in children than postoperative nausea because of a child's inability to effectively express distress after experiencing nausea. POV is problematic in children and is one of the leading postoperative complaints from parents and the leading cause of readmission to the hospital. POV occurs twice as frequently in children as in adults, increasing until puberty and then decreasing to adult incidence rates. Gender differences are not seen before puberty. POV remains a main cause of morbidity in children because severe vomiting can be associated with dehydration, postoperative bleeding, pulmonary aspiration, and wound dehiscence. While children have an increased potential for dehydration and the resulting physiologic impairments, other associated results such as a delay in hospital discharge or an overnight or longer hospital admission also must be considered. The two most common emetogenic surgical procedures evaluated in children are strabismus repair and adenotonsillectomy. The approach to the management of PONV and POV in children is similar to that in adults. However, as the rate of POV is more frequent in children than in adults, more children are candidates for antiemetic prophylaxis. The management approach is multifactorial and involves proper preoperative preparation, risk stratification, rational selection of antiemetic prophylaxis, choice of anesthesia technique, and a plan for postoperative antiemetic therapy. It is important to identify children at moderate-to-high risk for POV as prophylactic antiemetic therapy is useful in these children. Antiemetics of choice for POV in children include dexamethasone, dimenhydrinate, perphenazine, ondansetron, dolasetron, granisetron, and tropisetron. The serotonin (5-hydroxytryptamine; 5-HT(3)) antagonists are the antiemetic drugs of first choice for POV prophylaxis in children because as a group they have greater efficacy for preventing vomiting than nausea. The 5-HT(3) antagonists can be effectively combined with dexamethasone with an increase in efficacy. If possible, regional anesthesia should be considered. For those undergoing general anesthesia, the baseline POV risk should be reduced. Children at moderate-to-high PONV risk should receive combination therapy with two or three prophylactic antiemetics from different antiemetic drug classes. Reference to and the use of PONV guidelines and management algorithms help improve cost-effective postoperative care.

Intravenous droperidol: a review of its use in the management of postoperative nausea and vomiting

Droperidol (Dehydrobenzperidol, Dehidrobenzoperidol, Dridol, Droleptan, Inapsine) is a dopamine D(2) receptor antagonist that has been widely used in adults and children for the prevention and treatment of postoperative nausea and vomiting (PONV) over several decades and, more recently, for the prevention of opioid-induced PONV during patient-controlled analgesia (PCA) in adults. In well controlled clinical trials of patients undergoing surgery, the efficacy of single-dose intravenous (IV) droperidol in preventing PONV was similar to that of ondansetron and dexamethasone. Droperidol significantly reduced opioid-induced PONV in adults during PCA and had a morphine-sparing effect. Droperidol is generally well tolerated and the incidence of adverse effects is similar to that observed with placebo and the serotonin 5-HT(3) receptor antagonists (setrons). Guidelines recommend that, in adults, droperidol monotherapy be considered for those at moderate risk of PONV, and droperidol in combination with a setron and/or dexamethasone be considered for patients at moderate or high risk of PONV. In children with moderate or high risk of PONV, droperidol is recommended for first-line use in some countries, and second-line use in others.

A factorial study of ondansetron, metoclopramide, and dexamethasone for emesis prophylaxis after adenotonsillectomy in children

BACKGROUND

We conducted a factorial study of emesis prophylaxis with ondansetron (OND), metoclopramide (MET), and dexamethasone (DEX).

METHODS

After informed parental consent, 240 children having adenotonsillectomy were randomized to one of 15 combinations of OND (0-60 microg.kg(-1)), MET (0-400 microg.kg(-1)), and/or DEX (0-500 microg.kg(-1)). Using multivariable logistic regression, models were generated for the probability of emesis before discharge, after discharge and overall for 24 h.

RESULTS

Odds of emesis increased by a factor of three to four for children older than 7 years. Before discharge, odds of emesis decreased by factors of 0.29 for each 15 microg.kg(-1) of OND and 0.37 for each 100 microg.kg(-1) of MET. After discharge, odds of emesis decreased by a factor of 0.67 for each 125 microg.kg(-1) of DEX and increased by a factor of 3.5 for emesis before discharge. Over 24 h, odds of emesis decreased with OND, MET, and DEX (ORs as above). A negative interaction between OND and MET was seen before discharge and over 24 h, reducing the efficacy of their combination.

CONCLUSIONS

We present novel study design and methods of analysis which are uniquely suited to studies of multiple interventions. Factorial design was a powerful tool, allowing simultaneous determination of dose-response relationships for three drugs and identifying a previously unreported negative interaction between OND and MET.

Prophylaxis of postoperative vomiting in children undergoing tonsillectomy: a systematic review and meta-analysis

Postoperative vomiting (POV) remains one of the commonest causes of significant morbidity after tonsillectomy in children. A variety of prophylactic anti-emetic interventions have been reported, but there has only been a limited systematic review in this patient group. A systematic search was performed by using Cochrane Controlled Trials Register, MEDLINE and EMBASE to identify double-blind, randomized, placebo-controlled trials of prophylactic anti-emetic interventions in children undergoing tonsillectomy, with or without adenoidectomy. The outcome of interest was POV in the first 24 h. Summary estimates of the effect of each prophylactic anti-emetic strategy were derived using fixed effect meta-analysis. Where appropriate, dose-response effects were estimated using logistic regression and 22 articles were identified. Good evidence was found for the prophylactic anti-emetic effect of dexamethasone [odds ratio (OR) 0.23, 95% CI 0.16-0.33], and the serotinergic antagonists ondansetron (OR 0.36, 95% CI 0.29-0.46), granisetron (OR 0.11, 95% CI 0.06-0.19), tropisetron (OR 0.15, 95% CI 0.06-0.35) and dolasetron (OR 0.25, 95% CI 0.1-0.59). Metoclopramide was also found to be efficacious (OR 0.51, 95% CI 0.34-0.77). There is not sufficient evidence to suggest that dimenhydrinate, perphenazine or droperidol, in the doses studied, are efficacious, nor were gastric aspiration or acupuncture. In conclusion, dexamethasone and the anti-serotinergic agents appear to be the most effective agents for the prophylaxis for POV in children undergoing tonsillectomy.

Drugs for preventing postoperative nausea and vomiting

BACKGROUND

Drugs can prevent postoperative nausea and vomiting, but their relative efficacies and side effects have not been compared within one systematic review.

OBJECTIVES

The objective of this review was to assess the prevention of postoperative nausea and vomiting by drugs and the development of any side effects.

SEARCH STRATEGY

We searched The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2, 2004), MEDLINE (January 1966 to May 2004), EMBASE (January 1985 to May 2004), CINAHL (1982 to May 2004), AMED (1985 to May 2004), SIGLE (to May 2004), ISI WOS (to May 2004), LILAC (to May 2004) and INGENTA bibliographies.

SELECTION CRITERIA

We included randomized controlled trials that compared a drug with placebo or another drug, or compared doses or timing of administration, that reported postoperative nausea or vomiting as an outcome.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed trial quality and extracted outcome data.

MAIN RESULTS

We included 737 studies involving 103,237 people. Compared to placebo, eight drugs prevented postoperative nausea and vomiting: droperidol, metoclopramide, ondansetron, tropisetron, dolasetron, dexamethasone, cyclizine and granisetron. Publication bias makes evidence for differences among these drugs unreliable. The relative risks (RR) versus placebo varied between 0.60 and 0.80, depending upon the drug and outcome. Evidence for side effects was sparse: droperidol was sedative (RR 1.32) and headache was more common after ondansetron (RR 1.16).

AUTHORS' CONCLUSIONS

Either nausea or vomiting is reported to affect, at most, 80 out of 100 people after surgery. If all 100 of these people are given one of the listed drugs, about 28 would benefit and 72 would not. Nausea and vomiting are usually less common and, therefore, drugs are less useful. For 100 people, of whom 30 would vomit or feel sick after surgery if given placebo, 10 people would benefit from a drug and 90 would not. Between one to five patients out of every 100 people may experience a mild side effect, such as sedation or headache, when given an antiemetic drug. Collaborative research should focus on determining whether antiemetic drugs cause more severe, probably rare, side effects. Further comparison of the antiemetic effect of one drug versus another is not a research priority.

The effect of preoperative dexamethasone on early oral intake, vomiting and pain after tonsillectomy

OBJECTIVE

Postoperative morbidity in patients undergoing tonsillectomy with or without adenoidectomy includes inadequate oral intake, pain, nausea, vomiting and bleeding. The purpose of this study is to evaluate the effect of preoperative 0.5 mg/kg i.v. dexamethasone on postoperative early oral intake, pain, vomiting in patients undergoing adenotonsillectomy while performing standard anesthesia technique and sharp dissection tonsillectomy.

METHODS

In this prospective, double-blinded, placebo-controlled study 62 children, aged 4-12 years, who underwent tonsillectomy with or without adenoidectomy were randomly assigned to receive single dose of 0.5 mg/kg i.v. dexamethasone preoperatively. Patients started to receive 100 ml of clear fluids 2 h postoperatively, then were offered every hour. When pain score was 3 or above, paracetamol was given for pain control. Tolerating 400 ml of clear fluids, no bleeding and no vomiting were accepted as discharge criteria. The discharge time was also recorded. The incidence of early vomiting, pain scores, amount of oral intake were recorded until the discharge time.

RESULTS

Compared with placebo, the patients who received preoperative dexamethasone had significantly less pain score during the first 6 h postoperatively (p<0.05), adequate amount of oral intake time was shorter (p<0.05) and the discharge time was earlier (p<0.05). No difference was found in vomiting incidence in both groups.

CONCLUSION

Preoperative dexamethasone use significantly reduces early posttonsillectomy pain, improves oral intake and facilitates meeting the discharge criteria while using standard anesthesia technique and sharp dissection tonsillectomy without any significant side effects.

Single-dose dexmedetomidine reduces agitation and provides smooth extubation after pediatric adenotonsillectomy

BACKGROUND

Dexmedetomidine has shown sedative, analgesic, and anxiolytic effects after intravenous (IV) administration. Sevoflurane is associated with a high incidence of emergence agitation in preschool children. In this placebo-controlled study, we examined the effect of single dose dexmedetomidine on emergence agitation in children undergoing adenotonsillectomy.

METHODS

In a double-blinded trial, 60 children (age 3-7 years) were randomly assigned to receive dexmedetomidine 0.5 microg.kg(-1) IV or placebo, 5 min before the end of surgery. All patients received a standardized anesthetic regimen. For induction and maintenance of anesthesia we used sevoflurane. After surgery, the incidence and severity of agitation was measured 2 h postoperatively. The incidence of untoward airway events after extubation, such as breath holding, severe coughing, or straining were recorded. After surgery, the children's behavior and pain were assessed with a 5-point scale.

RESULTS

The agitation and pain scores in the dexmedetomidine group were better than those in the placebo group (P < 0.05). The incidence of severe agitation (a score of 4 or more), and severe pain (a score of 3 or more) were significantly less in the dexmedetomidine group (P < 0.05). The number of severe coughs per patient in the dexmedetomidine group was significantly decreased compared with the control group (P < 0.05). Postoperative vomiting was similar in both groups. Times to emergence and extubation were significantly longer in the dexmedetomidine group (P < 0.05).

CONCLUSIONS

We conclude that 0.5 microg.kg(-1) dexmedetomidine reduces agitation after sevoflurane anesthesia in children undergoing adenotonsillectomy.

An evaluation of pain and postoperative nausea and vomiting following the introduction of guidelines for tonsillectomy

BACKGROUND

Tonsillectomy and adenotonsillectomy have a high incidence of postoperative pain, and postoperative nausea and vomiting (PONV). Pain is traditionally controlled with morphine but this increases the risk of PONV and may cause respiratory depression. Antiemetics reduce PONV but their routine use has been questioned on safety grounds.

METHOD

After determining the current anesthetic management of elective tonsillectomy and adenotonsillectomy patients in our hospital, guidelines were developed to avoid the routine use of morphine and antiemetics. The effect on pain and PONV was then evaluated over a 3 month period. Postoperative pain was scored using the Oucher visual analog scale and nausea scored using a five point scale.

RESULTS

We analysed 34 cases to determine our current practice and 37 cases to evaluate the effect of introducing guidelines. Postguidelines, the median Oucher pain score at 4 h was 10, and at 8, 12, 16 h was zero. Despite receiving no antiemetics, only two children vomited (5%) after introduction of guidelines.

CONCLUSION

Guidelines which use a combination of paracetamol, nonsteroidal anti-inflammatory drugs and fentanyl, provide excellent analgesia with minimal PONV after elective tonsillectomy and adenotonsillectomy. As a result the routine use of morphine and antiemetics can be avoided.

Ondansetron Oral Disintegrating Tablets: Acceptability and Efficacy in Children Undergoing Adenotonsillectomy

Postoperative nausea and vomiting (PONV), a major complication in children, is responsive to IV and oral ondansetron. Because these routes are not always available, we studied the acceptability and efficacy of ondansetron oral disintegrating tablets (ODT). In this double-blind, randomized, placebo-controlled study, 62 patients undergoing adenotonsillectomy, aged 5 to 11 years, preoperatively received ODT (4 mg) or placebo. Patients assessed the medication for taste and sensation. Anesthesia was induced with sevoflurane, maintained with desflurane, and supplemented with fentanyl 2.5 microg/kg and dexamethasone 0.5 mg/kg (maximum dose, 12 mg). An observer blinded to treatment evaluated patients for pain, agitation, and PONV. Postoperative treatment consisted of fentanyl 1 microg/kg for pain and agitation and metoclopramide 0.15 mg/kg (maximum dose, 10 mg) for PONV. There were no significant differences between study groups with regard to age, weight, recovery time, agitation, or pain. Approximately 90% of the subjects found the ODT to taste good. No subject rejected the study medication, but the ondansetron-containing tablets were found to be less palatable than the placebo. The incidence of vomiting was significantly less in the ondansetron-medicated group.

RETRACTED: Results of a prospective, randomized, double-blind, placebo-controlled, dose-ranging trial to determine the effective dose of ramosetron for the prevention of vomiting after tonsillectomy in children

BACKGROUND

Postoperative vomiting (POV) is an important adverse effect of anesthesia and surgery, and children undergoing tonsillectomy may be particularly at risk.

OBJECTIVE

The aim of this study was to determine the effective dose of ramosetron, a 5-hydroxytryptamine type 3 receptor antagonist, for prophylaxis of severe POV (> or =2 episodes) in children undergoing general anesthesia for tonsillectomy.

METHODS

Standard general anesthetic technique and postoperative analgesia were used in this prospective, randomized, double-blind, placebo-controlled, dose-ranging trial of pediatric patients. Patients who had experienced POV, had taken an antiemetic medication within 24 hours before surgery of had a history of motion sickness were excluded. Only patients aged 4 to 10 years were included, because of their ability to answer questions. Patients received a single administration of either i.v. placebo or i.v. ramosetron at 3, 6, or 12 microg/kg immediately after the end of surgery. During the first 48 hours after anesthesia, episodes of retching, vomiting, and adverse events were recorded by nursing staff blinded to treatment assignment.

RESULTS

Eighty children (20 in each group)--42 girls and 38 boys--were enrolled. There were no differences in patient demographic characteristics among the treatment groups. The rates of complete response (no vomiting, retching, or need for another antiemetic medication) from 0 to 24 hours after anesthesia were 35% (7/20) with ramosetron 3 microg/kg, 90% (18/20) with ramosetron 6 micro/kg, and 90% (18/20) with ramosetron 12 microg/kg compared with placebo (30% [620], P=NS, P=0.001, and P=0.001 vs placebo, respectively); the corresponding rates from 24 to 48 hours after anesthesia were 35% (7/20), 90% (18/20), and 95% (19/20) compared with placebo (35% [7/20]; P=NS, P=0.001, and P=0.001 vs placebo, respectively). No difference in antiemetic efficacy was observed between ramosetron 6 and 12 microg/kg. No clinically serious adverse events attributable to the study drug were observed in any group.

CONCLUSIONS

In the pediatric population studied, ramosetron 6 microg/kg was effective for the prevention of vomiting after tonsillectomy from 0 to 48 hours after anesthesia. Increasing the dose to 12 microg/kg did not appear to provide further benefit.

Benefits and risks of newer treatments for chemotherapy-induced and postoperative nausea and vomiting

Nausea and vomiting are common adverse effects of chemotherapy, radiation therapy, anaesthesia and surgery. The incidence of chemotherapy-induced nausea and vomiting (CINV) is estimated to vary from 30 to 90%, depending on the type of chemotherapeutic agent used. Radiation-induced emesis varies with anatomical site radiated but is estimated to have an overall incidence of approximately 40%. The incidence of postoperative nausea and vomiting (PONV) depends on the type of anaesthesia and surgery, but overall is estimated to be 20-30%. Evidence-based medicine and meta-analysis have been used to direct medical therapy to help determine equivalence, optimal dose, timing, safety and efficacy of antiemetic medications. Concepts such as the number needed to treat and number needed to harm are helpful to guide the clinician regarding the benefits and risks of a particular treatment. The serotonin 5-HT(3) receptor antagonists ondansetron, granisetron, tropisetron and dolasetron have been important additions to the antiemetic armamentarium. The 5-HT(3) receptor antagonists are similar in chemical structure, efficacy and adverse effect profile. They appear to have no important differences among themselves in clinical outcomes for CINV and PONV. Headache, dizziness, constipation and diarrhoea are their most common adverse effects, and when they occur they are usually mild and easily managed. Haemodynamic changes and extrapyramidal adverse effects are uncommon. ECG changes such as prolonged corrected QT (QTc) interval are infrequent, dose-related and overall judged to be clinically insignificant. As most studies with the 5-HT(3) antagonists have been conducted on relatively healthy patients, caution should be exercised when these drugs are used in susceptible patients with co-morbidities. The clinician must weigh the benefit of administering an antiemetic for CINV or PONV against the risk of occurrence of an adverse event.

Management of postoperative nausea and vomiting in children

In spite of improvements in anesthesia techniques, the 'big little problem' of postoperative nausea and vomiting (PONV) still exists. PONV can prolong recovery room stay and hospitalization, and is one of the most common causes of hospital readmission after day surgery. While there is little evidence to support prophylactic administration of antiemetics in patients at low risk of PONV, the higher risk population could benefit from the use of adequate antiemetic drugs. A wide variety of pharmacological approaches have been reported to be effective, as well as some nonpharmacological approaches. Antiemetic drugs available to treat or prevent PONV include phenothiazines, antihistamines, anticholinergics, benzamides, butyrophenones and 5-HT(3) antagonists. Since available drugs still present undesired adverse effects and are not completely able to control PONV, clinical investigations are ongoing for more effective and better tolerated agents; indeed, the ideal antiemetic drug might be cost-effective for routine use.

Dexamethasone reduces postoperative vomiting and pain after pediatric tonsillectomy

PURPOSE

Previous studies on dexamethasone's antiemetic and analgesic potential in children undergoing tonsillectomy have produced conflicting results. The aim of this study was to evaluate the effects of a single dose of dexamethasone on the incidence and severity of postoperative vomiting and pain in children undergoing electrocautery tonsillectomy under standardized general anesthesia.

METHODS

In a double-blinded study, 120 patients were randomly allocated to receive either dexamethasone 0.5 mg.kg(-1) (maximum dose 8 mg) iv or an equivalent volume of saline preoperatively. The incidence of early and late vomiting, need for rescue antiemetics, time to first oral intake, time to first demand of analgesia and analgesic consumption were compared in both groups. Pain scores used included Children's Hospital Eastern Ontario Pain Scale, "faces", and a 0-10 visual analogue pain scale.

RESULTS

Compared with placebo, dexamethasone significantly decreased the incidence of early and late vomiting (P < 0.05, P < 0.001 respectively). Fewer patients in the dexamethasone group needed antiemetic rescue (P < 0.01). The time to first oral intake was shorter, and the time to first dose of analgesic was longer in the dexamethasone group (P < 0.01). Pain scores 30 min after extubation were lower (P < 0.05) in the dexamethasone group. At 12 and 24 hr postoperative swallowing was still significantly less painful in the dexamethasone group than in the control group (P < 0.01).

CONCLUSION

Preoperative dexamethasone 0.5 mg.kg(-1) iv reduced both postoperative vomiting and pain in children after electrocautery tonsillectomy.

Ondansetron for the prevention and treatment of nausea and vomiting following pediatric strabismus surgery

BACKGROUND

Neither droperidol nor ondansetron has been proven completely effective, and there are conflicting data comparing the efficacy of the two agents. The purpose of this study was to compare the efficacy, safety and cost of a combination of ondansetron administered intravenously in the operating room followed by oral ondansetron treatment at home with the more commonly used treatment of intravenous droperidol therapy and oral dimenhydrinate therapy, for the prevention and treatment of postoperative nausea and vomiting in children undergoing strabismus surgery.

METHODS

Double-blind randomized clinical trial with parallel comparison groups. All patients aged 6 months to 18 years who underwent strabismus surgery at a pediatric hospital in Montreal between Nov. 13, 2000, and June 12, 2001, were included. The exclusion criteria were nausea or vomiting, or use of antiemetics or narcotics in the 24 hours preceding surgery, and past history of hepatic, gastric or renal disease. The outcome measures were frequency of nausea and vomiting, severity of nausea and adverse effects in hospital, during transportation home and during the first 24 hours at home. Data were obtained through nursing notes and through a telephone interview conducted 24 to 48 hours after discharge.

RESULTS

Of the 208 eligible patients, 172 were randomly assigned to the study groups (88 to the ondansetron group and 84 to the droperidol/dimenhydrinate group). We found no statistically significant difference in the incidence of nausea and vomiting in hospital or at home between the two groups (25.3% vs. 31.6%, p = 0.371). There was a significant difference between the two groups in the rate of vomiting during transportation home (3.6% vs. 12.6%, p = 0.044). The incidence of severe nausea was 14.4% with ondansetron and 15.4% with droperidol, a nonsignificant difference (p = 1.00). No significant difference was observed between the two groups in the incidence of any nausea (p = 0.434) or adverse effects (p = 0.220). We calculated that the combination of droperidol and dimenhydrinate was seven times less costly than the ondansetron regimen.

INTERPRETATION

In this study, the efficacy and safety of intravenous administration of droperidol followed by oral use of dimenhydrinate did not differ from that of intravenous followed by oral use of ondansetron in children undergoing strabismus surgery. Since treatment with ondansetron is much more costly than the combination of droperidol and dimenhydrinate, at this time the use of ondansetron in the prevention and treatment of vomiting and nausea in this population may not be beneficial on a cost basis if all other variables are considered.

Ondansetron and dolasetron provide equivalent postoperative vomiting control after ambulatory tonsillectomy in dexamethasone-pretreated children

In this prospective, randomized, double-blinded, placebo-controlled study, we compared the incidence of emesis and 48-h recovery profiles after a single dose of preoperative ondansetron versus dolasetron in dexamethasone-pretreated children undergoing ambulatory tonsillectomy. One-hundred-forty-nine children, 2-12 yr old, ASA physical status I and II, completed the study. All children received standardized perioperative care, including premedication, surgical and anesthetic techniques, IV fluids, analgesics, and rescue antiemetic medications. Patients were randomized to receive ondansetron 0.15 mg/kg, maximum 4 mg (Group 1); dolasetron 0.5 mg/kg, maximum 25 mg (Group 2); or saline placebo (Group 3) IV before the initiation of surgery. In addition, all patients received dexamethasone 1 mg/kg (maximum 25 mg). Rescue antiemetics were administered for two or more episodes of retching/vomiting. The incidence of retching/vomiting before home discharge did not differ between the ondansetron and dolasetron groups and was significantly less frequent compared with the placebo group (10%, Group 1; 8%, Group 2; 30%, Group 3). Similar results were obtained at 24-48 h after discharge (6%, Groups 1 and 2; 18%, Group 3). The need for rescue antiemetics administered after the second retching/vomiting episode was significantly less in Groups 1 (4%) and 2 (6%) compared with Group 3 (22%) before home discharge. The complete response rate, defined as no retching/vomiting and no antiemetic for 48 h, was significantly increased in Groups 1 (76%) and 2 (74%) compared with Group 3 (44%). The antiemetic efficacy of prophylactic ondansetron and dolasetron was comparable in dexamethasone-pretreated children undergoing ambulatory tonsillectomy.

IMPLICATIONS

The efficacy of a single dose of prophylactic ondansetron versus dolasetron in conjunction with dexamethasone was studied on posttonsillectomy retching/vomiting and 48-h recovery in children 2-12 yr old. Compared with placebo, ondansetron and dolasetron produced comparable reductions in the incidence of retching/vomiting and the need for rescue antiemetics.

The addition of antiemetics to the morphine solution in patient controlled analgesia syringes used by children after an appendicectomy does not reduce the incidence of postoperative nausea and vomiting

BACKGROUND

We studied the effect of intraoperative ondansetron 0.1 mg x kg(-1) or droperidol 0.01 mg.kg-1, followed by the same dose of the antiemetic agent added to the morphine solution during patient controlled analgesia (PCA) on the incidence of nausea and vomiting in children following an appendicectomy.

METHODS

Sixty children, aged 5-13 years, were recruited and randomly allocated to receive no prophylactic antiemetic, the control group (group C), ondansetron (group O) or droperidol (group D). The PCA pump was programmed to deliver a bolus dose of 20 microg x kg(-1) of morphine.with a 5-min lockout period and a background infusion of 4 microg x kg(-1) x h(-1).

RESULTS

Postoperatively, the three groups were compared for nausea, vomiting and sedation scores for 24 h. The incidence of postoperative nausea and vomiting was 33% for group C, 44% for group O and 41% for group D. There was no increase in sedation scores in the droperidol group.

CONCLUSIONS

We were unable to show any significant benefit from the prophylactic administration of ondansetron or droperidol to children using morphine PCA devices following appendicectomy in the doses we employed.

Ondansetron: a review of its use as an antiemetic in children

Ondansetron, a selective serotonin (5-hydroxytryptamine; 5-HT) 5-HT3 receptor antagonist, is an antiemetic agent available for use in adults and children. In children receiving ondansetron (multiple 5 mg/m2 or 0.15 mg/kg intravenous and/or oral doses) in addition to chemotherapy in 2 large (n > 100) non-comparative analyses, < or =2 emetic episodes were observed in 33 and 40% of cisplatin recipients, 48 and 68% of ifosfamide recipients, and 70 and 72% of patients receiving other chemotherapeutic regimens. In comparative trials, ondansetron was significantly more effective at reducing nausea and vomiting than metoclopramide or chlorpromazine (both combined with dexamethasone), although the incidence of delayed symptoms were similar between children receiving ondansetron and metoclopramide. In addition, dexamethasone significantly improved the antiemetic efficacy of ondansetron in 1 randomised trial. When used in children undergoing conditioning therapy (including total body irradiation) prior to bone marrow transplantation, ondansetron was significantly better at controlling nausea and vomiting than combined perphenazine and diphenhydramine therapy. In dose-ranging and large placebo-controlled trials, intravenous (0.075 to 0.15 mg/kg) or oral (0.1 mg/kg) ondansetron was significantly more effective than placebo in preventing emesis in children undergoing surgery associated with a high risk of postoperative nausea and vomiting (PONV) including tonsillectomy or strabismus repair. In comparative studies, intravenous administration of ondansetron 0.1 to 0.15 mg/kg was significantly superior to droperidol 0.02 to 0.075 mg/kg or metoclopramide 0.2 to 0.25 mg/kg in preventing emesis in children undergoing various surgical procedures. In comparison with other antiemetics, including prochlorperazine and dimenhydrinate, ondansetron generally showed greater prophylactic antiemetic efficacy. Ondansetron combined with dexamethasone was significantly more effective than ondansetron or dexamethasone alone, as was the combination of ondansetron with a propofol-based anaesthetic compared with either agent alone. Ondansetron is generally well tolerated in children, rarely necessitating treatment withdrawal. The most frequently reported adverse events were mild to moderate headache, constipation and diarrhoea in patients receiving chemotherapy. Wound problems, anxiety, headache, drowsiness and pyrexia were reported most frequently in patients postsurgery.

CONCLUSIONS

Ondansetron has shown good efficacy in the prevention of acute nausea and vomiting in children receiving moderately or highly emetogenic chemotherapy and/or irradiation, particularly when combined with dexamethasone. In the chemotherapy setting, ondansetron is significantly better than metoclopramide and chlorpromazine and has a more favourable tolerability profile. In children undergoing surgery, ondansetron demonstrated superior prophylactic antiemetic efficacy compared with placebo, droperidol and metoclopramide, and was relatively free of adverse events. Ondansetron is thus an effective first-line antiemetic in children undergoing chemotherapy, radiotherapy and surgery.

Adenotonsillectomy in children: a comparison of morphine and fentanyl for peri-operative analgesia

This study compared the effectiveness and side-effects of intra-operative fentanyl with fentanyl and morphine for elective adenotonsillectomy in a double-blind study, in 60 children randomly allocated to receive either intravenous fentanyl 1 microg x kg(-1) intra-operatively or intramuscular morphine 100 microg x kg(-1) at induction. All children received a standard anaesthetic induction with intravenous fentanyl 1 microg x kg(-1) and propofol 4-5 mg x kg(-1) and maintenance with oxygen, nitrous oxide and isoflurane. Pain scores, emetic episodes and supplemental morphine requirements were recorded for 24 h postoperatively. The overall incidence of postoperative vomiting was high in both groups: 70% in the fentanyl group and 78% in the morphine group. The incidence of postoperative vomiting was lower in the fentanyl group (p < 0.03) in the first 4 h, but similar by 24 h. Children who received morphine at any time in the first 24 h had more median (range) episodes of vomiting [2 (0-7)] than children receiving fentanyl only [l (0-3); p < 0.03]. Administration of rescue anti-emetics, pain scores in recovery and pain scores over the next 24 h were similar between the two groups.

Acupuncture versus ondansetron in the prevention of postoperative vomiting. A study of children undergoing dental surgery

This study compares the anti-emetic effect of acupuncture with that of ondansetron and a placebo. Ninety children undergoing dental treatment under general anaesthesia were randomly allocated to one of the three equal groups, to receive acupuncture needle insertion, intravenous ondansetron 0.15 mg x kg(-1) or a placebo. Parental satisfaction scores and the incidence of emetic episodes were recorded. A significant difference was found in the number of patients who vomited and the total number of the emetic episodes when comparing the two treatment groups with the placebo group (p < 0.0001). A significant difference was also found between the treatment groups and the placebo group with respect to parental satisfaction score (p < 0.03). We conclude that traditional Chinese acupuncture is a valid non-pharmacological alternative anti-emetic treatment that can be recommended as a prophylactic technique in children undergoing dental surgery under general anaesthesia.