Nebulized opioids for the palliation of dyspnea in terminally ill patients

Abstract

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.

Keywords: dyspnea; end of life; nebulized; opioids; palliative care.