Nebulized Fentanyl for Dyspnea in a Hospice Patient with True Allergy to Morphine and Hydromorphone

Cancer-related breathlessness: opioids other than morphine - comprehensive literature review

INTRODUCTION

Although there is low-quality evidence, there has been an increase in publications on the experience of evaluating and managing cancer-related breathlessness using opioids other than morphine.

METHODS

The author conducted a non-systematic literature review in the PubMed/Medline and Embase until 4 October 2022. Eligible studies have evaluated the efficacy of opioids other than morphine for cancer-related breathlessness. Studies focused on sedation, anaesthesia, paediatric patients, opioid toxicity or basic research were excluded. Reviews/meta-analyses and non-English language publications were also excluded.

RESULTS

A total of 1556 records were identified, of which 23 studies including 469 patients who were treated with fentanyl (n=223), oxycodone (n=171) and hydromorphone (n=75) were considered eligible. Six phase II randomised clinical trials (RCTs), four observational studies and four case reports of fentanyl were found. For breathlessness on exertion, fentanyl yielded promising results, but no RCT showed significant superiority of fentanyl to placebo or morphine. For terminal breathlessness, three RCTs, five non-randomised or observational studies and one case report on oxycodone or hydromorphone were found. Although the results of the observational studies suggested that oxycodone and hydromorphone might be effective alternatives to morphine, the superiority over placebo or non-inferiority to morphine had not been demonstrated in the RCTs.

CONCLUSION

As an alternative to morphine, the author recommends fentanyl for breathless crisis or breathlessness on exertion, and oxycodone or hydromorphone for terminal breathlessness in advanced cancer. Larger and well-designed studies based on firm research policies are needed to confirm this current knowledge.

Opioid Management of Dyspnea at End of Life: A Systematic Review

Objective: The objective of this systematic review is to consolidate the existing evidence on opioid use, including administration, dosing, and efficacy, for the relief of dyspnea at end of life. The overarching goal is to optimize clinical management of dyspnea by identifying patterns in opioid use, improving opioid management of dyspnea, and to prioritize future research. Background: Opioids are commonly used in the management of dyspnea at end of life, yet specific administration guidelines are limited. A greater understanding of the effectiveness of opioids in relieving end-of-life dyspnea with consideration of study design, patients, and opioids, including dyspnea evaluation tools and outcomes, will leverage development of standardized administration and dosing. Methods: A PRISMA-guided systematic review using six databases identified quality studies of opioid management for patients with dyspnea at end of life. Results: Twenty-three references met review inclusion criteria, which included terminally ill cancer and noncancer patients with various diagnoses. Studies included two randomized controlled trials, and three nonrandomized experimental, three prospective observational, one cross-sectional, and one case series. Thirteen retrospective chart reviews were also included due to the limited rigorous studies rendered by the search. Thirteen studies evaluated morphine, followed by fentanyl (6), oxycodone (5), general opioid use (4), and hydromorphone (2). Routes of administration were parenteral, oral, combination, and nebulization. Dyspnea was evaluated using self-reporting and non-self-reporting evaluation tools. Sedation was the most reported opioid-related adverse effect. Discussion: Challenges persist in conducting end-of-life research, preventing consensus on standardization of opioid treatment for dyspnea within this specific palliative time frame. Future robust prospective trials using specific, accurate assessment with reassessment of dyspnea/respiratory distress, and consideration of opioid tolerance, polypharmacy, and comorbidities are required.

Inspiratory neural drive and dyspnea in interstitial lung disease: Effect of inhaled fentanyl

BACKGROUND

Exertional dyspnea in interstitial lung disease (ILD) remains difficult to manage despite advances in disease-targeted therapies. Pulmonary opioid receptors present a potential therapeutic target for nebulized fentanyl to provide dyspnea relief.

METHODS

ILD patients were characterized with reference to healthy volunteers. A randomized, double-blind, placebo-controlled crossover comparison of 100 mcg nebulized fentanyl vs placebo on dyspnea intensity and inspiratory neural drive (IND) during constant work rate (CWR) cycle exercise was performed in 21 ILD patients.

RESULTS

Dyspnea intensity in ILD increased in association with an increase in IND (diaphragm activation) from a high resting value of 16.66 ± 6.52 %-60.04 ± 12.52 % of maximum (r = 0.798, p < 0.001). At isotime during CWR exercise, Borg dyspnea intensity ratings with fentanyl vs placebo were 4.1 ± 1.2 vs 3.8 ± 1.2, respectively (p = 0.174), and IND responses were also similar.

CONCLUSION

IND rose sharply during constant work rate exercise in association with dyspnea intensity in mild to moderate ILD but was not different after nebulized fentanyl compared with placebo.

Nebulized Fentanyl for Dyspnea: A Retrospective Chart Review

Nebulized fentanyl is well established for analgesia but its use for dyspnea requires further investigation. The aim of our study was to determine the effectiveness of nebulized fentanyl in treating patients with dyspnea and to determine if there were harmful side effects described by patients or their providers. We used a convenience sample of patients from July 1 2014 to July 1 2018 and performed a retrospective chart review. We found that 360 doses of nebulized fentanyl were given to 73 patients during that time period. Of the 73 patients evaluated, 32 patients (43.8%) were female and forty-one were male (56.1%). The median age was 67 and the median length of stay was 9 days. There were no documented findings of bronchospasm, hypotension, or allergic reaction in any of the medical records reviewed. Patients treated with nebulized fentanyl for dyspnea showed a mean decreased respiratory rate of 4.3 breaths/min and a mean increased oxygen saturation of 2.3%. Also, 71% of patients with documented responses experienced an improvement in their dyspnea. Our preliminary data suggest that nebulized fentanyl has limited side effects and may have a role in the treatment of dyspnea. Further research is necessary to determine its efficacy.

Relationship between MRGPRX2 and pethidine hydrochloride- or fentanyl citrate-induced LAD2 cell degranulation

OBJECTIVES

Pethidine hydrochloride (PH) and fentanyl citrate (FC) are opioid receptor agonists commonly used to treat pain clinically. PH and FC have been reported to have a high potential for pseudoallergic effects, but the underlying mechanism has not been well studied. MRGPRX2 is a novel atypical opioid receptor that is mainly expressed in human mast cells and considered to mediate drug-induced pseudoallergic reactions. This study aimed to investigate the allergy effect of these two opioid receptor agonists and the possible association of MRGPRX2 with this response.

METHODS

HEK293-MRGPRX2/CMC assay, molecular docking assay, calcium mobilization assay, the test of β-hexosaminidase, histamine and cytokine release assay were performed in this article.

KEY FINDINGS

PH but not FC induced LAD2 cell activation and degranulation dose-dependently. Histamine, tumour necrosis factor (TNF)-α, interleukin (IL)-8, monocyte chemotactic protein 1 (MCP-1) and macrophage inflammatory protein (MIP-1β) levels were upregulated by PH, but not FC. The PH-induced activation of mast cell was MRGPRX2-dependent.

CONCLUSIONS

PH but not FC activated mast cells, leading to degranulation mediated via MRGPRX2 receptors, which could be greatly significant in future clinical applications of opioid receptor drugs.