Analgesic interaction between ondansetron and acetaminophen after tonsillectomy in children: The Paratron randomized, controlled trial

A scoping review of randomized clinical trials for pain management in pediatric tonsillectomy and adenotonsillectomy

Objectives

To examine the volume, topics, and reporting trends in the published literature of randomized clinical trials for pharmacologic pain management of pediatric tonsillectomy and adenotonsillectomy and to identify areas requiring further research.

Data Sources

PubMed (National Library of Medicine and National Institutes of Health), Scopus (Elsevier), CINAHL (EBSCO), and Cochrane Library (Wiley).

Methods

A systematic search of four databases was conducted. Only randomized controlled or comparison trials examining pain improvement with a pharmacologic intervention in pediatric tonsillectomy or adenotonsillectomy were included. Data collected included demographics, pain-related outcomes, sedation scores, nausea/vomiting, postoperative bleeding, types of drug comparisons, modes of administration, timing of administration, and identities of the investigated drugs.

Results

One hundred and eighty-nine studies were included for analysis. Most studies included validated pain scales, with the majority using visual-assisted scales (49.21%). Fewer studies examined pain beyond 24 h postoperation (24.87%), and few studies included a validated sedation scale (12.17%). Studies have compared several different dimensions of pharmacologic treatment, including different drugs, timing of administration, modes of administration, and dosages. Only 23 (12.17%) studies examined medications administered postoperatively, and only 29 (15.34%) studies examined oral medications. Acetaminophen only had four self-comparisons.

Conclusion

Our work provides the first scoping review of pain and pediatric tonsillectomy. With drug safety profiles considered, the literature does not have enough data to determine which treatment regimen provides superior pain control in pediatric tonsillectomy. Even common drugs like acetaminophen and ibuprofen require further research for optimizing the treatment of posttonsillectomy pain. The heterogeneity in study design and comparisons weakens the conclusions of potential systematic reviews and meta-analyses. Future directions include more noninferiority studies of unique comparisons and more studies examining oral medications given postoperatively.

The Effects of Ondansetron on the Analgesic Action of Intravenous Acetaminophen after Tonsillectomy in Children: A Triple-Blind Randomized Controlled Trial

Introduction

Severe pain, nausea, and vomiting after tonsillectomy surgery are among the issues that not only affect patient satisfaction but also may result in complications and delay patient discharge. This study was conducted to assess the effect of intravenous administration of ondansetron on the analgesic action of intravenous acetaminophen after tonsillectomy in children. Materials and methods. This randomized controlled trial was conducted on 53 children between the age of 3 and 12 years old who were referred to Besat Hospital Hamadan, Iran, for tonsillectomy. Patients were randomly assigned to two groups. The intervention group (I) received intravenous acetaminophen plus 0.1 mg/kg ondansetron intravenously while the control group (C) received intravenous acetaminophen plus 2 ml of normal saline intravenously. Postoperative pain severity was assessed using the Children's Hospital Eastern Ontario Pain Scale (CHEOPS). Frequency of nausea, vomiting, and need for analgesic was assessed and recorded four times, at recovery unit, after 6, 12, and 24 hours postsurgery. Data analysis was performed at 95% confidence level using the statistical package for social sciences (SPSS) software version 21.

Results

The number of patients in groups I and C was 27 and 26 patients, respectively. Mean pain score in I and C groups was 4.48 and 2.88 at recovery unit, 2.74 and 2.04 after 6 hours, 1.67 and 0.81 after 12 hours, and 0.67 and 0.20 after 24 hours postsurgery, respectively. Frequency of nausea at recovery unit was 23.1% in I group and 0.0% in group C (p = 0.010) while the mean number of analgesic requirements in I and C groups was 1.07 and 0.56 times, respectively (p = 0.027).

Conclusions

Intravenous administration of 0.1 mg/kg ondansetron reduces the analgesic action of intravenous acetaminophen after tonsillectomy in 3 to 12-year-old children.

Postoperative Nausea and Vomiting in Pediatric Patients

Postoperative nausea and vomiting (PONV), postoperative vomiting (POV), post-discharge nausea and vomiting (PDNV), and opioid-induced nausea and vomiting (OINV) continue to be causes of pediatric morbidity, delay in discharge, and unplanned hospital admission. Research on the pathophysiology, risk assessment, and therapy for PDNV, OINV and pain therapy options in children has received increased attention. Multimodal pain management with the use of perioperative regional and opioid-sparing analgesia has helped decrease nausea and vomiting. Two common emetogenic surgical procedures in children are adenotonsillectomy and strabismus repair. Although PONV risk factors differ between adults and children, the approach to decrease baseline risk is similar. As PONV and POV are frequent in children, antiemetic prophylaxis should be considered for those at risk. A multimodal approach for antiemetic and pain therapy involves preoperative risk evaluation and stratification, antiemetic prophylaxis, and pain management with opioid-sparing medications and regional anesthesia. Useful antiemetics include dexamethasone and serotonin 5-hydroxytryptamine-3 (5-HT3) receptor antagonists such as ondansetron. Multimodal combination prophylactic therapy using two or three antiemetics from different drug classes and propofol total intravenous anesthesia should be considered for children at high PONV risk. "Enhanced recovery after surgery" protocols include a multimodal approach with preoperative preparation, adequate intravenous fluid hydration, opioid-sparing analgesia, and prophylactic antiemetics. PONV guidelines and management algorithms help provide effective postoperative care for pediatric patients.

The effect of ondansetron on analgesic efficacy of acetaminophen after hysterectomy: A randomized double blinded placebo controlled trial

OBJECTIVES

To determine that perioperative ondansetron reduces the analgesic efficacy of acetaminophen.

DESIGN

Randomized, double-blinded study.

PATIENTS

120 patients ASA I-II who underwent abdominal hysterectomy.

INTERVENTIONS

All the patients were given 1g acetaminophen at skin closure. Patients were divided into two groups; ondansetron HCl (8mg, 2ml IV) (Group I, N=60) and saline (2ml IV) (Group II, N=60) at the skin closure.

MEASUREMENT

Postoperative pain scores (VAS) while resting in bed and sitting, total opioid consumption were noted.

MAIN RESULTS

Patients randomized to ondansetron had significantly worse pain scores upon arrival to the recovery unit [by 1.7 (99.7% CI: 0.75, 2.59) cm] and at 1h [by 1.3 (0.5, 2.1) cm] while resting in bed. Pain scores while sitting were also significantly greater in ondansetron group at arrival in PACU by 0.6 (99.7% CI: 0.1, 1.0) cm. Thereafter, pain scores did not differ significantly. Median total opioid (tramadol) consumption was 441 [Q1, Q3: 280, 578] mg in the ondansetron group and 412 [309, 574] mg in the placebo group, P=0.95.

CONCLUSIONS

Ondansetron significantly decreased the analgesic effect of acetaminophen during the initial postoperative period. Our results thus confirm that acetaminophen analgesia is partially mediated by serotonin receptors. However, the reduction was of marginal clinical importance and short-lived.

Endogenous Opiates and Behavior: 2015

This paper is the thirty-eighth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2015 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia, stress and social status, tolerance and dependence, learning and memory, eating and drinking, drug abuse and alcohol, sexual activity and hormones, pregnancy, development and endocrinology, mental illness and mood, seizures and neurologic disorders, electrical-related activity and neurophysiology, general activity and locomotion, gastrointestinal, renal and hepatic functions, cardiovascular responses, respiration and thermoregulation, and immunological responses.