A Systematic Review of Measures of Breakthrough Pain and Their Psychometric Properties

A rapid systematic review of breakthrough pain definitions and descriptions

Background

Breakthrough pain is common in life-limiting conditions and at end-of-life. Despite over 30 years of study, there is little consensus regarding the definition and characteristics of breakthrough pain.

Objective

This study aims to update and expand a 2010 systematic review by Haugen and colleagues to identify (1) all definitions of breakthrough pain and (2) all descriptions and classifications of breakthrough pain reported by patients, caregivers, clinicians, and experts.

Design

This rapid systematic review followed the Cochrane Rapid Review Methods Group guidelines. A protocol is published on PROSPERO (CRD42019155583).

Data sources

CINAHL, MEDLINE, PsycINFO, and the Web of Science were searched for breakthrough pain terms from the inception dates of each database to 26th August 2022.

Results

We identified 65 studies that included data on breakthrough pain definitions, descriptions, or classifications from patients (n = 30), clinicians (n = 6), and experts (n = 29), but none with data from caregivers. Most experts proposed that breakthrough pain was a sudden, severe, brief pain occurring in patients with adequately controlled mild-moderate background pain. However, definitions varied and there was no consensus. Pain characteristics were broadly similar across studies though temporal factors varied widely. Experts classified breakthrough pain into nociceptive, neuropathic, visceral, somatic, or mixed types. Patients with breakthrough pain commonly experienced depression, anxiety, and interference with daily life.

Conclusions

Despite ongoing efforts, there is still no consensus on the definition of breakthrough pain. A compromise is needed on breakthrough pain nomenclature to collect reliable incidence and prevalence data and to inform further refinement of the construct.

Definition and Assessment of Paediatric Breakthrough Pain: A Qualitative Interview Study

Infants, children and young people with life-limiting or life-threatening conditions often experience acute, transient pain episodes known as breakthrough pain. There is currently no established way to assess breakthrough pain in paediatric palliative care. Anecdotal evidence suggests that it is frequently underdiagnosed and undertreated, resulting in reduced quality of life. The development of a standardised paediatric breakthrough pain assessment, based on healthcare professionals' insights, could improve patient outcomes. This study aimed to explore how healthcare professionals define and assess breakthrough pain in paediatric palliative care and their attitudes towards a validated paediatric breakthrough pain assessment. This was a descriptive qualitative interview study. Semi-structured interviews were conducted with 29 healthcare professionals working in paediatric palliative care across the UK. An inductive thematic analysis was conducted on the data. Five themes were generated: 'the elusive nature of breakthrough pain', 'breakthrough pain assessment', 'positive attitudes towards', 'reservations towards' and 'features to include in' a paediatric breakthrough pain assessment. The definition and assessment of breakthrough pain is inconsistent in paediatric palliative care. There is a clear need for a validated assessment questionnaire to improve assessment, diagnosis and management of breakthrough pain followed by increased healthcare professional education on the concept.

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.

Effects of esketamine on postoperative rebound pain in patients undergoing unilateral total knee arthroplasty: a single-center, randomized, double-blind, placebo-controlled trial protocol

Introduction

Rebound pain, transient and acute postoperative pain after the disappearance of regional block anesthesia, has been a concern in recent years. Insufficient preemptive analgesia and hyperalgesia induced by regional block are the main mechanisms. At present, the evidence for the treatment of rebound pain is limited. The esketamine, as an antagonist of the N-methyl-D-aspartate receptor, has been proven to prevent hyperalgesia. Therefore, this trial aims to evaluate the impact of esketamine on postoperative rebound pain in patients undergoing total knee arthroplasty.

Methods/design

This study is a single-center, prospective, double-blind, randomized, placebo-controlled trial. Participants who plan to undergo total knee arthroplasty will be randomly assigned to the esketamine group (N = 178) and placebo group (N = 178) in a ratio of 1:1. This trial aims to evaluate the impact of esketamine on postoperative rebound pain in patients undergoing total knee arthroplasty. The primary outcome of this trial is the incidence of rebound pain within 12 h after the operation in the esketamine group and the placebo group. The secondary outcome will be to compare (1) the incidence of rebound pain 24 h after the operation; (2) the time to enter the pain cycle for the first time within 24 h after the procedure; (3) the first time of rebound pain occurred within 24 h after surgery; (4) the modified rebound pain score; (5) NRS score under rest and exercise at different time points; (6) the cumulative opioid consumption at different time points; (7) patient's prognosis and knee joint function evaluation; (8) blood glucose and cortisol concentration; (9) patient's satisfaction score; (10) adverse reactions and adverse events.

Discussion

The effect of ketamine on preventing postoperative rebound pain is contradictory and uncertain. The affinity of esketamine to the N-methyl-D-aspartate receptor is about four times higher than levo-ketamine, the analgesic effect is 3 times higher than levo-ketamine, and there are fewer adverse mental reactions. To our knowledge, there is no randomized controlled trial to verify the impact of esketamine on postoperative rebound pain in patients undergoing total knee arthroplasty. Therefore, this trial is expected to fill an important gap in relevant fields and provide novel evidence for individualized pain management.

Clinical Trial Registration

http://www.chictr.org.cn, identifier ChiCTR2300069044.

Retrospective Observational Study on the Characteristics of Pain and Associated Factors of Breakthrough Pain in Advanced Cancer Patients

Objective

This study aimed to conduct a retrospective observational study to understand the status of characteristics of pain and identify potential variables influencing the clinical presentation of breakthrough cancer pain (BTP) in advanced cancer patients.

Methods

Advanced cancer patients over 18 years of age; diagnosed with cancer of any type and stage III or IV in the palliative care ward with available data were enrolled between 2018 and 2020. Demographic data and pain-related information were collected by using structured electronic extraction form from Hospital Information System (HIS). Patients who had well-controlled background pain with an intensity ≤4 on a 0–10 numerical scale for >12 hours/day, the presence of transient exacerbations of pain with moderate-severe intensity (≧5), and clearly distinguish from background pain were regarded to have suffered BTP. Spearman correlation was conducted to explore the relationship between pain score and demographics characteristics. Factors significant in univariate analysis were included in the multiple regression model to explore independent predictive factors associated with the BTP.

Results

Of 798 advanced cancer patients, the mean age was 56.7 (SD = 11.84) years. Lung cancer (29.95%) was the most common cancer, and pain (93%) was the most common symptom. More than half (n = 428, 53.6%) of the patients experienced BTP. The median number of BTP episodes was 4 (IQR = 2, 7, range: 1–42). The median intensity of BTP was 6 (IQR = 6, 7, range 5–10). Patients with severe background pain or BTP had longer hospital stay and more symptoms. Besides, more severe background pain was related to higher activity of daily living. Intramuscular injection of hydromorphone hydrochloride was the main medication for BTP onset. Younger age, background pain, anorexia, and constipation were independently associated with the presentation of BTP. BTP pain intensity was independently associated with bloating. Symptom numbers were an independent factor and positively associated with BTP episodes.

Conclusions

BTP resulted in poor prognosis, which has a variable presentation depending on interdependent relationships among different characteristics. Good controlling of background pain and assessment of pain-related symptoms are essential for BTP management. BTP should be managed individually, especially the invisible pain among aged patients. Furthermore, BTP-related education and training were still needed.

Healthcare Professionals' Experiences of the Barriers and Facilitators to Pediatric Pain Management in the Community at End-of-Life: A Qualitative Interview Study

CONTEXTS

Inadequate pain management in community pediatric palliative care is common. Evidence to inform improved pain management in this population is limited.

OBJECTIVES

To explore the barriers and facilitators to pediatric community-based pain management for infants, children and young people at end-of-life as perceived by healthcare professionals.

METHODS

A qualitative interview study was conducted. Semi-structured interviews were undertaken with 29 healthcare professionals; 12 nurses, five GPs, five consultants and registrar doctors, two pharmacists and five support therapists working in primary, secondary or tertiary care in the United Kingdom and involved in community end-of life care of 0 to 18-year-olds.

RESULTS

The data corpus was analyzed using an inductive thematic analysis and seven themes emerged: parents' abilities, beliefs and wellbeing; working relationships between families and healthcare professionals, and between healthcare teams; healthcare professionals' knowledge, education and experience; health services delivery; nature of pain treatment; and pediatric-specific factors. Across themes, the concepts of partnership working between families and healthcare professionals, and within healthcare teams, and sharing expertise were prevalent.

CONCLUSION

Partnership working and trust between healthcare professionals and parents, and within healthcare teams, is needed for effective at-home pediatric palliative pain management. Community healthcare professionals require more education from experienced multidisciplinary teams to effectively manage pediatric pain at end-of-life and prevent emergency hospice or hospital admissions, particularly during the COVID-19 pandemic.