Intravenous Fentanyl for Dyspnea at the End of Life: Lessons for Future Research in Dyspnea

Objectives: To determine the efficacy of intravenous (IV) Fentanyl in dyspnoeic patients with advanced cancer. Methods: Dyspnoeic patients with advanced cancer satisfying the selection criteria received (IV) Fentanyl and were evaluated for response 24 hours post-administration in a prospective observational study. Results: Altogether 36 patients were enrolled into the study. However, data from only 16 patients could be analysed as 20 patients had died or were too sick to self-report scores. Seven out of 16 patients responded to IV Fentanyl although the result was not statistically significant (non-responders versus responders: 56.3% vs 43.8%, p = 0.33). The strongest correlations for variables predictive of responder status were the absence of anxiety and lung metastases. Conclusions: This exploratory study shows that IV Fentanyl can alleviate dyspnea in some patients but is an example of the difficulties conducting dyspnea research. Future studies would benefit from novel developments in the areas of measuring dyspnea in dying patients and statistical analysis of small sample sizes.