Effect of nebulized morphine in cancer patients with dyspnea: a pilot study

Nebulized opioids for the palliation of dyspnea in terminally ill patients

PURPOSE

The use of nebulized opioids for the palliation of dyspnea in terminally ill patients is reviewed.

SUMMARY

More than 50% of patients with advanced diseases experience dyspnea during their final stages of life. Systemically administered opioids are recommended for the management of dyspnea in these patients, but adverse effects may limit their use. Nebulization offers an alternative route for administering opioids, providing relief of dyspnea while minimizing adverse events. An extensive literature search was conducted to identify publications evaluating nebulized opioids for the palliation of dyspnea in patients at end-of-life. Ten studies that evaluated nebulized morphine, fentanyl, hydromorphone, and morphine-6-glucuronide were reviewed; 1 of these studies evaluated 4 different opioids. Of these 10 studies, 2 had double-blind, placebo-controlled, randomized crossover designs; 1 was retrospective, and the remaining 7 were prospective studies. A total of 181 patients, all adults, were evaluated. Subjective improvement in dyspnea from baseline was observed in 9 of the 10 studies. Nebulized morphine 20 mg every 4 hours was the most common opioid studied. Other doses of nebulized opioids included fentanyl 25 and 100 μg and hydromorphone 5 mg. Nine studies reported subjective improvement of dyspnea from baseline after administering nebulized opioids. Six studies evaluated objective outcomes and showed decreased respiratory rate (morphine, fentanyl, and hydromorphone) and heart rate (hydromorphone) and increased oxygen saturation (fentanyl). Mild-to-moderate adverse effects such as claustrophobia due to nebulizer mask, drowsiness, cough, and bitter taste were described.

CONCLUSION

Nebulized opioids may provide subjective relief of dyspnea in terminally ill patients with mild-to-moderate adverse effects.

Dosimetrically administered nebulized morphine for breathlessness in very severe chronic obstructive pulmonary disease: a randomized, controlled trial

BACKGROUND

Systemic morphine has evidence to support its use for reducing breathlessness in patients with severe chronic obstructive pulmonary disease (COPD). The effectiveness of the nebulized route, however, has not yet been confirmed. Recent studies have shown that opioid receptors are localized within epithelium of human trachea and large bronchi, a target site for a dosimetric nebulizer. The aim of this study was to compare any clinical or statistical differences in breathlessness intensity between nebulized 2.0% morphine and 0,9% NaCl in patients with very severe COPD.

METHODS

The study was a double-blind, controlled, cross-over trial. Participants received morphine or NaCl during two 4-day periods. Sequence of periods was randomized. The primary outcome measure was reduction of breathlessness intensity now by ≥20 mm using a 100 mm visual analogue scale (VAS) at baseline, 15, 30, 60, 120, 180 and 240 min after daily administration, during normal activities.

RESULTS

Ten of 11 patients included completed the study protocol. All patients experienced clinically and statistically significant (p < 0.0001) breathlessness reduction during morphine nebulization. Mean VAS changes for morphine and 0.9% NaCl periods were 25.4 mm (standard deviation (SD): 9.0; median: 23,0; range: 14.0 to 41,5; confidence interval (CI): 95%) and 6.3 mm (SD: 7.8; median: 6.8; range: -11,5 to 19,5; CI: 95%), respectively. No treatment emergent adverse effects were noted.

DISCUSSION

Our study showed superiority of dosimetrically administered nebulized morphine compared to NaCl in reducing breathlessness. This may have been achieved through morphine's direct action on receptors in large airways, although a systemic effect from absorption through the lungs cannot be excluded.

TRIAL REGISTRATION

Retrospectively registered (07.03.2017), ISRCTN14865597.

Respiratory adverse effects of opioids for breathlessness: a systematic review and meta-analysis

Previous studies have shown that opioids can reduce chronic breathlessness in advanced disease. However, physicians remain reluctant to prescribe opioids for these patients, commonly due to fear of respiratory adverse effects. The aim of this study was to systematically review reported respiratory adverse effects of opioids in patients with advanced disease and chronic breathlessness.PubMed, Embase, the Cochrane Central Register of Controlled Trials, CINAHL, ClinicalTrials.gov and the reference lists of relevant systematic reviews were searched. Two independent researchers screened against predefined inclusion criteria and extracted data. Meta-analysis was conducted where possible.We included 63 out of 1990 articles, describing 67 studies. Meta-analysis showed an increase in carbon dioxide tension (0.27 kPa, 95% CI 0.08-0.45 kPa,) and no significant change in oxygen tension and oxygen saturation (both p>0.05). Nonserious respiratory depression (definition variable/not stated) was described in four out of 1064 patients. One cancer patient pretreated with morphine for pain needed temporary respiratory support following nebulised morphine for breathlessness (single case study).We found no evidence of significant or clinically relevant respiratory adverse effects of opioids for chronic breathlessness. Heterogeneity of design and study population, and low study quality are limitations. Larger studies designed to detect respiratory adverse effects are needed.

Nebulized Morphine for Relief of Dyspnea Due to Chronic Lung Disease

OBJECTIVE:

To evaluate the efficacy and safety of nebulized morphine for the management of dyspnea in chronic pulmonary diseases.

DATA SOURCES:

MEDLINE (1966–May 2004), EMBASE (1980–May 2004), and International Pharmaceutical Abstracts (1970–May 2004) searches were performed. Key search terms included morphine, dyspnea, and inhalation.

DATA SYNTHESIS:

Nine studies have evaluated the efficacy of nebulized morphine in relieving dyspnea. Three trials had positive resuts, but the rest failed to show improvement after treatment with doses ranging from 1 to 40 mg nebulized morphine. The small number of subjects, variety of disease states, and different outcome measures limit interpretation of the studies.

CONCLUSIONS:

Results from several small studies do not support the use of nebulized morphine for treatment of dyspnea; however, several positive case reports have been published.

Opioids for the Management of Dyspnea in Cancer Patients: Evidence of the Last 15 Years--A Systematic Review

The objective of this study was to review the evidence on the use of opioids for treatment of the dyspnea in adult cancer patients. A systematic literature review was conducted in the databases MEDLINE, CINAHL (EBSCO), ScienceDirect, and Cochrane Library of trials testing the effect of opioids in relieving dyspnea in cancer patients. Fourteen trials met the criteria for inclusion in the review. Eight randomized trials and six nonrandomized trials. All randomized clinical trials analyzed present risks of bias. Morphine has been the most studied strong opioid showing efficacy in alleviating dyspnea when administered, either orally or subcutaneously, in cancer patients. The potential benefit of the strong opioids in the alleviation of dyspnea in cancer patients is modest and limited to some opioids. More studies are needed to sufficiently support the role of opioids in dyspnea at rest, at exertion, and for breakthrough dyspnea and to clarify the safety issues.

Effect of nebulized morphine on dyspnea of mustard gas-exposed patients: a double-blind randomized clinical trial study

Background. Dyspnea is one of the main complaints in a group of COPD patients due to exposure to sulfur mustard (SM) and is refractory to conventional therapies. We designed this study to evaluate effectiveness of nebulized morphine in such patients. Materials and Methods. In a double-blind clinical trial study, 40 patients with documented history of exposure to SM were allocated to two groups: group 1 who received 1 mg morphine sulfate diluted by 4 cc normal saline 0.5% using nebulizer once daily for 5 days and group 2 serving as control who received normal saline as placebo. They were visited by pulmonologist 7 times per day to check symptoms and signs and adverse events. Different parameters including patient-scored peak expiratory flow using pick flow meter, visual analogue scale (VAS) for dyspnea, global quality of life and cough, and number of respiratory rate, night time awaking for dyspnea and cough have been assessed. Results. The scores of VAS for dyspnea, cough and quality of life and also respiratory rate, heart rate, and night time awaking due to dyspnea and night time awaking due to cough improved significantly after morphine nebulization without any major adverse events. Also pick expiratory flow has been improved significantly after nebulization in each day. Conclusion. Our results showed the clinical benefit of nebulized morphine on respiratory complaints of patients due to exposure to SM without significant side effects.

Relief of incident dyspnea in palliative cancer patients: a pilot, randomized, controlled trial comparing nebulized hydromorphone, systemic hydromorphone, and nebulized saline

Acute episodic breathlessness in patients receiving palliative care is a distressing symptom with little evidence-base to inform management. This pilot, double-blind, controlled, crossover study compared the effects of nebulized hydromorphone, systemic hydromorphone and nebulized saline for the relief of episodic breathlessness in advanced cancer patients. On three occasions of acute breathlessness, patients randomly received either nebulized hydromorphone, a systemic breakthrough dose of hydromorphone or nebulized saline together with a blinding agent. Breathlessness was scored before and 10, 20, 30, and 60 minutes post-treatment completion using a 100 mm visual analog scale. Twenty patients completed the trial. Ratings did not differ significantly across pretest treatments. Change in ratings from pretest to 10 minutes after completion of nebulization (about 20 minutes after administration of systemic hydromorphone) indicated that each of the treatments resulted in statistically significant improvements in breathlessness, with no significant differences between treatments. Over time, breathlessness decreased significantly for all treatments, with no significant differences between treatments. Only nebulized hydromorphone produced a rapid improvement in breathlessness that reached a magnitude considered to be clinically important. Interpretation of these results is considered in relation to our definition of clinical significance, the dose of hydromorphone used and the possibility of a placebo effect. This study can serve to inform the design of future trials to investigate the management of incident breathlessness.

Dyspnea Management in Lung Cancer: Applying the Evidence From Chronic Obstructive Pulmonary Disease

PURPOSE/OBJECTIVES

To provide an overview of mechanisms of dyspnea and causes of dyspnea in chronic obstructive pulmonary disease (COPD) and lung cancer and to critically review current pharmacologic and nonpharmacologic management of dyspnea for COPD and lung cancer.

DATA SOURCES

Published articles, abstracts, textbooks, and the authors' personal experiences with dyspnea management in COPD and lung cancer.

DATA SYNTHESIS

The causes of dyspnea in cancer are more varied than the causes of dyspnea in COPD; however, many are similar, thus providing the justification for recommending best practice from COPD research to be used in lung cancer. Dyspnea in both diseases is treated by corticosteroids, bronchodilators, antianxiety drugs, local anesthetics, and oxygen. However, when dyspnea is severe, morphine is the first choice. Using specific breathing techniques, positioning, energy conservation, exercise, and some dietary modifications and nutrient supplements can help with dyspnea management.

CONCLUSIONS

Pharmacologic and nonpharmacologic management of dyspnea in COPD can be applied to dyspnea related to lung cancer. Further research in the management of dyspnea in lung cancer is required, particularly controlled studies with larger sample sizes, to determine the effectiveness of the application of COPD dyspnea management in lung cancer.

IMPLICATIONS FOR NURSING

Previous studies provide a guideline for applying dyspnea management for COPD to cancer. The theoretical frameworks used in previous studies can be modified for conducting further study.

The Use of Nebulized Opioids in the Management of Dyspnea: Evidence Synthesis

PURPOSE/OBJECTIVES

To analyze the evidence about the use of nebulized opioids to treat dyspnea using the Priority Symptom Management (PRISM) level-of-evidence framework and to make a practice recommendation.

DATA SOURCES

Computerized database and manual search for articles and abstracts that included experimental trials, chart reviews, and case studies.

DATA SYNTHESIS

20 articles with evaluable evidence were identified. Analysis was complex because of heterogeneous variables and outcome measures. A major limitation is small sample sizes. The majority of PRISM level I and II studies indicated unfavorable evidence.

CONCLUSIONS

Scientific data supporting the use of nebulized opioids to treat dyspnea in patients with chronic pulmonary disease, including malignancy, are lacking.

IMPLICATIONS FOR NURSING

Insufficient data identify a need for further research with random crossover designs involving larger samples that are stratified according to prior opioid use. Consistency of study variables should be emphasized.

Dyspnea

Dyspnea, defined as uncomfortable or labored breathing, is a common and often devastating cause of distress for patients and their caregivers with advanced cancer and other life-threatening illnesses. The mechanism by which dyspnea develops is not fully understood, but it involves integration of the central respiratory complex with the sensory (perceptual) cortex. The gold standard of diagnosis is patient self-report. Careful assessment should be undertaken to identify reversible existing causes. Systemic opioids are the first-line therapy for symptomatic management, along with other general comfort measures (positioning, cool air, calming environment). Medical or surgical management can be directed toward underlying causes. Advanced care planning should include discussions concerning the burdens and benefits of medical/surgical management of underlying causes of dyspnea to more effectively direct goals of care. This article reviews current literature on dyspnea, with a focus on items published since 2000.

Opioids, respiratory function, and dyspnea

Dyspnea, the sensation of difficult breathing, is a common debilitating symptom in advanced cancer and chronic progressive cardiopulmonary disease. Primary treatment is correction of the underlying etiology. In incurable illness wherein the cause is irreversible and the goal is palliation, opioids are the drugs of choice for symptomatic relief. This article reviews current knowledge in the pathophysiology of dyspnea, proposed opioid mechanism of action, and evidence of efficacy.

Nebulized morphine as a treatment for dyspnea in a child with cystic fibrosis

OBJECTIVE

To shed light on nebulized morphine, a new treatment for dyspnea in children with terminal lung disease.

METHODS

A clinical case study was conducted on a patient in a tertiary care medical center.

RESULTS

Nebulized morphine was administered in incremental doses ranging from 2.5 mg to 12.5 mg in a 10-year-old, 20-kg boy with end-stage cystic fibrosis. Before the nebulized morphine treatments were started, a dose of nebulized lidocaine failed to provide the patient with any relief. After each dose of morphine, the following parameters were recorded: visual analog "dyspnea" scores, vital signs, venous blood gases, and blood levels of morphine. The nebulized morphine was found to have a modest effect on the patient's dyspnea, with no significant differences found between the varying doses. Venous carbon dioxide tension levels increased <4 mm Hg for all doses except 12.5 mg, for which there was a 9-mm Hg increase. Systemic blood levels of morphine were <10 ng/mL at all doses. The nebulized morphine did not cause any significant changes in blood pressure or heart rate for doses <12.5 mg.

CONCLUSIONS

Inhaled morphine was associated with a mild, beneficial effect on dyspnea, with minimal differences found between the lowest and highest doses. This "ceiling" effect may be the result of saturation of opioid receptors in the lung, the variable bioavailability of inhaled morphine, or a placebo response. More studies are needed to determine what, if any, the optimum dose of nebulized morphine is for children.

Development of inhalational agents for oncologic use

Because regional chemotherapy has been useful in treatment and palliation of many cancer types, the concept of delivering drugs by inhalation for the treatment of cancers in the lung is attractive. Much higher local drug exposure can be achieved with total doses considerably lower than those required for systemic administration, resulting in lower exposure of nonrespiratory tract tissues to potentially toxic drugs. Regional delivery of chemotherapy to the respiratory tract has been shown to have activity in preclinical and clinical studies. Technical improvements in delivery methods have now made it possible to conduct trials of inhalational agents, both to treat cancers affecting the respiratory tract and to deliver other drugs used in cancer patients. This review discusses the rationale of drug delivery by the inhalational route, its technical challenges, preclinical and clinical experiences, limitations, and promise.