Chronic obstructive pulmonary disease (COPD)
COPD is a functional category of pulmonary disorders that are indicative of persistent obstruction of airflow through the bronchi. Bronchitis and emphysema are often referred to as COPD. The first is characterized by chronic or recurrent excessive mucus production and the latter is a condition of the lung characterized by permanent, abnormal enlargement of airspaces. Both disorders are indicated by tests of abnormal expiratory flow (reduced maximal expiratory flow and low FEV 1 ).