[From understanding the pathophysiological mechanisms of dyspnea to the correct symptomatic treatment].

Breathing discomfort is one of the most common and distressing symptoms experienced by patients. Various pathophysiologic mechanisms underlie the symptom of dyspnea, and multiple mechanisms may be present in a given patient. The evaluation of the dyspneic patient must begin with a thorough history examining the key characteristics of the symptom, including quality, intensity, duration, frequency, and distress. The words utilized by patients to describe their breathing discomfort may provide insights into the underlying pathophysiology of their disease. Treatment for dyspnea should be selected based on the pathophysiologic mechanisms involved and not only according to the specific disease. Attempts are made to reduce mechanical impedance (by reducing lung hyperinflation by bronchodilators or surgical volume reduction), to reduce ventilatory demand (by exercise training), to improve inspiratory muscle function (by inspiratory muscle training), to alter breathing patterns, to begin supplemental oxygen therapy and to reduce central perception. It is often necessary to combine several treatment modalities in order to achieve a significant reduction in dyspnea.