Antonio Anzueto, M.D. N Engl J Med 2010; 363:1280-1281September 23, 2010
Chronic obstructive pulmonary disease (COPD) is characterized by progressive limitation of airflow that results in air trapping and hyperinflation. Some patients with this disease also have irreversible pulmonary emphysema due to the destruction of alveolar septa in the lung.1
These abnormalities are manifested as breathlessness, limited activity, and impaired quality of life.1 Hyperinflation itself makes the respiratory muscles inefficient both at rest and during exertion. The diaphragm and intercostal muscles in these patients have important structural muscle-fiber abnormalities, as well as alterations in signaling pathways and increased expression of inflammatory cytokines.2 , 3 On the basis of these observations, reducing pulmonary . . .
