Re: Relief of Incident Dyspnea in Palliative Cancer Patients

Abstract

I have read with great interest the excellent study carried out by Charles et al.,1Charles M. Reymond L. Israel F. Relief of incident dyspnea in palliative cancer patients: a pilot, randomized, controlled trial comparing nebulized hydromorphone, systemic hydromorphone, and nebulized saline.J Pain Symptom Manage. 2008; 36: 29-38Abstract Full Text Full Text PDF PubMed Scopus (66) Google Scholar which contributes greatly to attempts to alleviate breathlessness toward the end of life. There are very few randomized studies on this topic, and even fewer on the management of incidental dyspnea in patients with advanced cancer. I do, however, wish to make a few comments. It is striking that one arm of the study did not include nebulized morphine. Although the systematic reviews carried out by Jennings et al.2Jennings A. Davies A. Higgins J. Gibbs J. Broadley K. A systematic review of the use of opioids in the management of dyspnoea.Thorax. 2002; 57: 939-944Crossref PubMed Scopus (500) Google Scholar and Viola et al.3Viola R. Kiteley C.S. Lloyd N. et al.The management of dyspnea in cancer patients: a systematic review.Support Care Cancer. 2008; 16: 329-337Crossref PubMed Scopus (93) Google Scholar show that there are insufficient data to conclude whether nebulized opioids are effective, recent studies indicate that nebulized morphine may be equally as effective as subcutaneous morphine.4Bruera E. Sala R. Spruyt O. et al.Nebulized versus subcutaneous morphine for patients with câncer dyspnea: a preliminary study.J Pain Symptom Manage. 2005; 29: 613-618Abstract Full Text Full Text PDF PubMed Scopus (71) Google Scholar Although scarce, the largest studies are conducted with morphine. It is unclear whether a decrease of one cm on the dyspnea visual analog scale represents a significant improvement (as with the other symptoms on the Edmonton Symptom Assessment Scale); the authors rely on the work of Jennings et al.2Jennings A. Davies A. Higgins J. Gibbs J. Broadley K. A systematic review of the use of opioids in the management of dyspnoea.Thorax. 2002; 57: 939-944Crossref PubMed Scopus (500) Google Scholar and Abernethy,5Abernethy A. Currow D. Frith P. et al.Randomised, double blind, placebo controlled crossover trial of sustained release morphine for the management of refractory dyspnoea.BMJ. 2003; 327: 523-528Crossref PubMed Google Scholar which, however, do not explicitly reflect this assertion. Although the study was done in cancer patients, two patients with chronic obstructive pulmonary disease were not excluded. It is not clear whether the breathlessness in these cases (2 out of 20) is related to cancer or chronic obstructive pulmonary disease. We know of no studies that support the assertion that an analgesic dose of hydromorphone provides significant improvement for incidental dyspnea; however, in the discussion section, the authors assume this as a fact, without citing articles in this regard.