From Tramadol to Methadone: Opioids in the Treatment of Pain and Dyspnea in Pediatric Palliative Care

What we know and what we don't know about the perioperative use of methadone in children and adolescents

Postoperative pain control is essential to optimizing patient outcomes, improving satisfaction, and allowing patients to resume their baseline functional activities. Methadone, a synthetic mu-opioid agonist, has multiple pharmacologic properties that may be optimal for perioperative use. Compared to other opioids, methadone has a longer duration of action, rapid onset, extended dosing intervals, high oral bioavailability, low cost, lack of active metabolites, and action on multiple receptors. The current literature examining the use of methadone in the perioperative care of children and adolescents is limited and most often reported within the context of spine or cardiothoracic surgery. Overall, these studies support the hypothesis that perioperative methadone in pediatric patients may decrease postoperative pain, opioid consumption, length-of-stay, and the incidence of some opioid-related side effects, like constipation and urinary retention. A variety of protocols for the perioperative use of methadone have been described, including a single intraoperative dose as well as multiple small doses within multimodal pain protocols. The superiority of these protocols has not been established. Like all opioids, methadone has a side effect profile which includes nausea, vomiting, reduced GI motility, sedation, and respiratory depression at high doses. There is also a concern that it can cause QTc prolongation in patients. The primary aim of this educational review is to examine the pharmacologic data, published perioperative protocols, dosing considerations, and risks and benefits associated with inclusion of methadone in analgesic regimens for surgical patients. A secondary aim is to introduce opportunities for research around the perioperative use of methadone in children and adolescents. Based on our review, we would prioritize establishing optimal procedure-specific methadone protocols, determining generalizability for use in routine pediatric surgeries, and investigating methadone safety and efficacy prospectively as the primary opioid for pain management in the postanesthesia care unit or postsurgical floors.

Tramadol Use in Pediatric Surgery: Trends After the Food and Drug Administration Black-Box Warning

INTRODUCTION

The U.S. Food and Drug Administration (FDA) issued a black-box warning in 2017 contraindicating tramadol in children <12 y. Longitudinal trends and factors associated with perioperative tramadol use in children remain unclear.

METHODS

A retrospective, multi-institutional cohort study utilizing the Pediatric Health Information System database was performed for children 2-18 y who underwent one of ten common surgeries from 1/2009-2/2020. Temporal trends correlated with the FDA tramadol contraindication were evaluated. Hierarchical multivariable logistic regression analysis identified factors associated with tramadol use.

RESULTS

Of 477,153 children undergoing surgery, 5857(1.2%) received tramadol during hospitalization. Tramadol use occurred in 942 (16.1%) children after the black-box warning, 390 of whom were <12 y. For children <12 y, annual tramadol use peaked at 1.87% (2016) and decreased to 0.66% (2019). Female sex (odds ratio OR 1.32; 95% confidence interval CI:1.24,1.40), age ≥12 y (OR 2.79; 95%CI: 2.62,2.97), and Midwest location (OR 4.07; 95% CI:1.64,10.11) increased likelihood of receiving tramadol. Tramadol use was more likely after cholecystectomy (OR 1.17; 95% CI:1.04,1.32) and in children with gastrointestinal (OR 2.39; 95% CI: 2.19,2.60), metabolic (OR 1.39; 95% CI:1.26,1.53) or transplant-related (OR 1.82; 95% CI: 1.57,2.10) comorbidities. Children of Hispanic/Latino ethnicity and those with public insurance had decreased likelihood of receiving tramadol. Adjusting for patient and hospital characteristics, children <12 y were less likely to receive tramadol following the black-box warning (OR 0.65; 95% CI: 0.59,0.70).

CONCLUSIONS

Despite the FDA contraindication, tramadol prescribing continues among children <12 y undergoing surgery, with use varying by patient and institutional factors. Interventions are required to reduce perioperative tramadol use in children.

Old Drug, New Pain. Roles and Challenges of Methadone Therapy in Pediatric Palliative Care: A Systematic Review

BACKGROUND

Pediatric palliative care (PPC) is defined as the prevention and relief from suffering of families and children with life-limiting (LLDs) or life-threatening diseases (LTDs). These patients often experience pain, with morphine being the most widely used drug to treat it. Few studies investigated the role of methadone in PPC patients, although it is considered among the most effective and underutilized drugs in PPC.

OBJECTIVES

Our aim was to evaluate the efficacy, safety, and dosage of methadone in PPC.

METHODS

Between August and October 2021 PubMed, Scopus and the Cochrane Library were searched for studies on the use of methadone in children with LLDs and LTDs. Articles were included if they met the following criteria: published in the last 10 years, English language, patients aged 0-23 years; children enrolled in a PPC center or receiving declared support from a PPC service; reporting of specific data on methadone in interventional trials, observational studies, or case series on >10 patients. The reporting of the article was guided by the PRISMA guidelines, and a critical appraisal of the included studies was performed using the JBI-tool.

RESULTS

After duplicates removal and full-text assessment, four studies were included and another one was added after checking the references of the retrieved papers. All were retrospective, and the literature is concordant in documenting the lack of evidence. A total of 116 children received methadone in PPC. From our review emerges the poor quality of data collection: in only one study pain was assessed with standardized scales. All studies documented the effectiveness of methadone in treating complex pain, either nociceptive or neuropathic. No serious adverse events were reported, with no cases of cardiac arrhythmias.

CONCLUSION

Our results suggest that methadone could represent a suitable strategy for treating pain in PPC. However, the evidence base is insufficient, and further research is warranted.

[Pediatric pain treatment and prevention for hospitalized children]

INTRODUCTION

Prevention and treatment of pain in pediatric patients compared with adults is often not only inadequate but also less often implemented the younger the children are. Children 0 to 17 years are a vulnerable population.

OBJECTIVES

To address the prevention and treatment of acute and chronic pain in children, including pain caused by needles, with recommended analgesic starting doses.

METHODS

This Clinical Update elaborates on the 2019 IASP Global Year Against Pain in the Vulnerable "Factsheet Pain in Children: Management" and reviews best evidence and practice.

RESULTS

Multimodal analgesia may include pharmacology (eg, basic analgesics, opioids, and adjuvant analgesia), regional anesthesia, rehabilitation, psychological approaches, spirituality, and integrative modalities, which act synergistically for more effective acute pediatric pain control with fewer side effects than any single analgesic or modality. For chronic pain, an interdisciplinary rehabilitative approach, including physical therapy, psychological treatment, integrative mind-body techniques, and normalizing life, has been shown most effective. For elective needle procedures, such as blood draws, intravenous access, injections, or vaccination, overwhelming evidence now mandates that a bundle of 4 modalities to eliminate or decrease pain should be offered to every child every time: (1) topical anesthesia, eg, lidocaine 4% cream, (2) comfort positioning, eg, skin-to-skin contact for infants, not restraining children, (3) sucrose or breastfeeding for infants, and (4) age-appropriate distraction. A deferral process (Plan B) may include nitrous gas analgesia and sedation.

CONCLUSION

Failure to implement evidence-based pain prevention and treatment for children in medical facilities is now considered inadmissible and poor standard of care.

Pediatric pain treatment and prevention for hospitalized children

Introduction:

Prevention and treatment of pain in pediatric patients compared with adults is often not only inadequate but also less often implemented the younger the children are. Children 0 to 17 years are a vulnerable population.

Objectives:

To address the prevention and treatment of acute and chronic pain in children, including pain caused by needles, with recommended analgesic starting doses.

Methods:

This Clinical Update elaborates on the 2019 IASP Global Year Against Pain in the Vulnerable “Factsheet Pain in Children: Management” and reviews best evidence and practice.

Results:

Multimodal analgesia may include pharmacology (eg, basic analgesics, opioids, and adjuvant analgesia), regional anesthesia, rehabilitation, psychological approaches, spirituality, and integrative modalities, which act synergistically for more effective acute pediatric pain control with fewer side effects than any single analgesic or modality. For chronic pain, an interdisciplinary rehabilitative approach, including physical therapy, psychological treatment, integrative mind–body techniques, and normalizing life, has been shown most effective. For elective needle procedures, such as blood draws, intravenous access, injections, or vaccination, overwhelming evidence now mandates that a bundle of 4 modalities to eliminate or decrease pain should be offered to every child every time: (1) topical anesthesia, eg, lidocaine 4% cream, (2) comfort positioning, eg, skin-to-skin contact for infants, not restraining children, (3) sucrose or breastfeeding for infants, and (4) age-appropriate distraction. A deferral process (Plan B) may include nitrous gas analgesia and sedation.

Conclusion:

Failure to implement evidence-based pain prevention and treatment for children in medical facilities is now considered inadmissible and poor standard of care.

Emerging Challenges to the Safe and Effective Use of Methadone for Cancer-Related Pain in Paediatric and Adult Patient Populations

Methadone continues to be an important medication for the treatment of paediatric and adult cancer-related pain. Appropriate patient selection to ensure safe and effective treatment by a team of clinicians who appreciate and are familiar with methadone and its unique pharmacology is crucial. Unlike morphine and other more common opioids, methadone is purported to have involvement with delta-opioid receptor and higher affinity as an N-methyl-D-aspartate-receptor antagonist. Clinically this gives it the advantage of being effective for both nociceptive and neuropathic pain, but also may be useful in the setting of tolerance to other opioids. Methadone also comes in multiple available formulations that can be administrated through a variety of routes beyond the oral route. Challenges with methadone in treating cancer-related pain include drug interactions specifically as it relates to new targeted cancer therapies. Recent guidelines recommend electrocardiogram monitoring with methadone and there is potential for additive cardiac toxicity in the oncology setting. Appropriate dosing of methadone for pain management given age, organ dysfunction, and patients who are on methadone maintenance therapy are also key factors. This article aims to provide clinicians with evidence and clinical practice guidelines for safe and appropriate use of methadone including indication, initiation, and monitoring given its complexity for management of pain in the dynamic oncology setting.

Recent advances in pain treatment for children with serious illness

Pain is a common distressing symptom in children receiving pediatric palliative care. Both in children with cancer, but especially in children with progressive neurodegenerative and chromosomal conditions with CNS impairment pain is common, and often under-recognized and undertreated. Multimodal analgesia for children with serious illness acts synergistically for more effective pediatric pain and symptom control with fewer side effects than a single analgesic or modality. Successful pain treatment and prevention usually include integrative 'nonpharmacological' therapies, rehabilitation, psychology and spirituality in addition to pharmacology and regional anesthesia. This review article will address these effective components of multimodal pediatric analgesia and present starting doses of basic analgesia, opioids and adjuvants analgesia in infants, children and adolescents with serious illness.

Buccal opioids for breakthrough pain in children with life-limiting conditions receiving end-of-life care

BACKGROUND

Many palliative care health settings that care for children and young people (CYP) at the end of life use the buccal mucosa as a route of drug administration to manage the sudden onset of symptoms, such as seizures, agitation and dyspnoea, and for breakthrough pain management. The buccal route is a minimally invasive method that delivers fast symptom relief and is useful for those with swallowing impairment or reduced enteral absorption.

AIM

This paper reports on a small retrospective study involving 26 CYP who received end-of-life care between January and December 2017 to review the advantages and disadvantages of using buccal opioids for breakthrough pain relief with a focus on diamorphine as the preferred opioid.

METHOD

A retrospective case note review.

FINDINGS

This paper shares the clinical practice experiences from one UK organisation of care for CYP at the end of their lives and contributes to the growing body of pharmacological evidence.

CONCLUSION

Buccal opioids, specifically buccal diamorphine, are an effective strategy to treat breakthrough pain or dyspnoea in CYP.