The management of dyspnea in cancer patients: a systematic review.
The goal of the study is to evaluate the effectiveness of four drug classes (opioids, phenothiazines, benzodiazepines, and systemic corticosteroids) for relieving dyspnea experienced by advanced cancer patients. A systematic literature review was conducted to July 2006. Search sources included MEDLINE, EMBASE, HealthSTAR, CINAHL, and the Cochrane Library. Four reviewers selected evidence using predefined criteria: controlled trials not limited to cancer and involving the specified drug classes for dyspnea treatment. Three systematic reviews, one with meta-analysis, two practice guidelines, and 28 controlled trials were identified. Most examined the effect of opioids, generally morphine, on dyspnea. Although the results of individual trials were mixed, the systematic review with meta-analysis detected a significant benefit for dyspnea with systemic opioids; two small placebo-controlled trials in cancer patients found systemic morphine reduced dyspnea, and dihydrocodeine also significantly reduced dyspnea in four placebo-controlled trials. Nebulized morphine was not effective in controlling dyspnea in any study or the meta-analysis. No controlled trials examined systemic corticosteroids in the treatment of cancer patients, and of the other non-opioid drugs examined, only oral promethazine, a phenothiazine, showed some benefit in the relief of dyspnea. Studies varied in methodological quality. Systemic opioids, administered orally or parenterally, can be used to manage dyspnea in cancer patients. Oral promethazine may also be used, as a second-line agent if systemic opioids cannot be used or in addition to systemic opioids. Nebulized morphine, prochlorperazine, and benzodiazepines are not recommended for the treatment of dyspnea, and promethazine must not be used parenterally.