COPD is a major cause of increased morbidity, hospital readmission, mortality, and health-care use. In 2010, the direct cost of COPD in the United States was estimated to be in excess of $49 billion per year. Data from the United States inpatient nationwide sample from 2001 to 2012 revealed that hospitalization rates for common cardiovascular disorders, pneumonia, and lung cancer were reduced significantly, whereas for COPD the rehospitalization rate increased during the same period. The primary cause of hospitalization and emergency health-care admissions in patients with COPD is severe acute exacerbation, defined by increased dyspnea, increased cough, and purulent sputum present for at least 48 h. Readmission to short-term care for this group of patients is common and costly and is associated with impaired quality of life and increased burden to the caregiver. Furthermore, severe exacerbations that trigger hospital readmission may represent a life-threatening event and use of the ICU.