The etiology and management of intractable breathlessness in patients with advanced cancer: a systematic review of pharmacological therapy.

Intractable breathlessness is a common, devastating symptom of advanced cancer causing distress and isolation for patients and families. In advanced cancer, breathlessness is complex and usually multifactorial and its severity unrelated to measurable pulmonary function or disease status. Therapeutic advances in the clinical management of dyspnea are limited and it remains difficult to treat successfully. There is growing interest in the palliation of breathlessness, and recent work has shown that a systematic, evidence-based approach by a committed multidisciplinary team can improve lives considerably. Where such care is lacking it may be owing to therapeutic nihilism in clinicians untrained in the management of chronic breathlessness and unaware that there are options other than endurance. Optimum management involves pharmacological treatment (principally opioids, occasionally oxygen and anxiolytics) and nonpharmacological interventions (including use of a fan, a tailor-made exercise program, and psychoeducational support for patient and family) with the use of parenteral opioids and sedation at the end of life when appropriate. Effective care centers on the patient's needs and goals. Priorities in breathlessness research include studies on: neuroimaging, the effectiveness of new interventions, the efficacy, safety, and dosing regimens of opioids, the contribution of deconditioning, and the effect of preventing or reversing breathlessness.