Healthcare professionals' views of the use of oral morphine and transmucosal diamorphine in the management of paediatric breakthrough pain and the feasibility of a randomised controlled trial: A focus group study (DIPPER)

Intranasal Therapy in Palliative Care

In recent years, the use of the intranasal route has been actively explored as a possible drug delivery method in the palliative patient population. There are reports demonstrating the effectiveness of nasally administered medications that are routinely used in patients at the end of life. The subject of this study is the intranasal drug administration among palliative patients. The aim is to summarize currently used intranasal therapies among palliative patients, determine the benefits and difficulties, and identify potential areas for future research. A review of available medical literature published between 2013 and 2023 was performed using online scientific databases. The following descriptors were used when searching for articles: "palliative", "intranasal", "nasal", "end-of-life care", "intranasal drug delivery" and "nasal drug delivery". Out of 774 articles, 55 directly related to the topic were finally selected and thoroughly analyzed. Based on the bibliographic analysis, it was shown that drugs administered intranasally may be a good, effective, and convenient form of treatment for patients receiving palliative care, in both children and adults. This topic requires further, high-quality clinical research.

Diamorphine pharmacokinetics and conversion factor estimates for intranasal diamorphine in paediatric breakthrough pain:systematic review

BACKGROUND

Intranasal diamorphine is a potential treatment for breakthrough pain but few paediatric data are available to assist dose estimation.

AIM

To determine an intranasal diamorphine dose in children through an understanding of pharmacokinetics.

DESIGN

A systematic review of the literature was undertaken to seek diamorphine pharmacokinetic parameters in neonates, children and adults. Parenteral and enteral diamorphine bioavailability were reviewed with respect to formation of the major metabolite, morphine. Clinical data quantifying equianalgesic effects of diamorphine and morphine were reviewed.

REVIEW SOURCES

PubMed (1960-2020); EMBASE (1980-2020); IPA (1973-2020) and original human research studies that reported diacetylmorphine and metabolite after any dose or route of administration.

RESULTS

The systematic review identified 19 studies: 16 in adults and 1 in children and 2 neonatal reports. Details of study participants were extracted. Age ranged from premature neonates to 67 years and weight 1.4-88 kg. Intranasal diamorphine bioavailability was predicted as 50%. The equianalgesic intravenous conversion ratio of morphine:diamorphine was 2:1. There was heterogeneity between pharmacokinetic parameter estimates attributed to routes of administration, lack of size standardisation, methodology and pharmacokinetic analysis. Estimates of the pharmacokinetic parameters clearance and volume of distribution were reduced in neonates. There were insufficient paediatric data to characterise clearance or volume maturation of either diamorphine or its metabolites.

CONCLUSIONS

We estimate equianalgesic ratios of intravenous morphine:diamorphine 2:1, intravenous morphine:intranasal diamorphine 1:1 and oral morphine:intranasal diamorphine of 1:3. These ratios are based on adult literature, but are reasonable for deciding on an initial dose of 0.1 mg/kg in children 4-13 years.

Oral morphine versus transmucosal diamorphine for breakthrough pain in children: methods and outcomes: UK (DIPPER study) consensus

OBJECTIVES

No randomised controlled trials have been conducted for breakthrough pain in paediatric palliative care and there are currently no standardised outcome measures. The DIPPER study aims to establish the feasibility of conducting a prospective randomised controlled trial comparing oral and transmucosal administration of opioids for breakthrough pain. The aim of the current study was to achieve consensus on design aspects for a small-scale prospective study to inform a future randomised controlled trial of oral morphine, the current first-line treatment, versus transmucosal diamorphine.

METHODS

The nominal group technique was used to achieve consensus on best practice for mode of administration, dose regimen and a range of suitable pain intensity outcome measures for transmucosal diamorphine in children and young people with breakthrough pain. An expert panel of ten clinicians in paediatric palliative care and three parent representatives participated. Consensus was achieved when agreement was reached and no further comments from participants were forthcoming.

RESULTS

The panel favoured the buccal route of administration, with dosing according to the recommendations in the Association for Paediatric Palliative Medicine formulary (fifth Edition, 2020). The verbal Numerical Rating Scale was selected to measure pain in children 8 years old and older, the Faces Pain Scale-Revised for children between 4 and 8 years old, and Face, Legs, Activity, Cry and Consolability (FLACC)/FLACC-Revised as the observational tools.

CONCLUSIONS

The nominal group technique allowed consensus to be reached for a small-scale, prospective, cohort study and provided information to inform the design of a randomised controlled trial.

Carer preferences of route of administration of transmucosal diamorphine and willingness to take part in a randomised controlled trial: an interview study (DIPPER)

Background

Children and young people are usually given liquid morphine by mouth for breakthrough pain, which can take thirty minutes to work. A faster-acting, quickly absorbed, needle-free pain medicine, that is easy to administer is needed such as transmucosal (sublingual, buccal, intranasal) diamorphine. Research evidence relating to the administration of medication for breakthrough pain in children and young people is limited. This study aims to describe the experiences and preferences of parents and/or children and young people regarding the route of administration of diamorphine, barriers and facilitators comparative to oral morphine, and participation in a randomised controlled trial.

Methods

In-depth, semi-structured interviews with parents and/or children and young people at home or hospital/hospice.

Results

Thirteen interviews with: nine mothers, one father, and three sets of parents jointly. No interviews took place with a child/young person. Most families had experience of the buccal route which was effective in ease of administration and time to control pain. The intranasal route was preferred by parents irrespective of experience. Parents’ willingness for their child to take part in a trial depended on the time commitment, their child’s pain trajectory and the stability of analgesic requirements.

Conclusion

A randomised controlled trial of oral morphine versus transmucosal diamorphine would need to consider trial logistics, especially time commitment. Parents felt that the trial should be introduced initially by the clinical team, with written information from the research team, and sufficient time to ask questions. Patients who had discontinued oral morphine because of side effects, or those with gastrointestinal failure, should be excluded. Maintaining stability in pain management was essential to families, so the timing of the trial is a potential issue.