慢性阻塞性肺病(COPD)是呼吸系统常见疾病，国内外均占较大比例。COPD是一组以最大呼气流量降低，肺用力排空速度减慢为特点且这些特点在几月内不发生显著变化的疾病。大部分气流受限进展缓慢且不可逆。部分患者进展为肺心病、呼吸衰竭。一般病人每年有1～4次的急性加重或急 Chronic obstructive pulmonary disease (COPD) is a common respiratory disease, both at home and abroad account for a large proportion. COPD is a group of diseases characterized by a reduction in maximum expiratory flow and slowing of forced lung emptying, and these characteristics do not change significantly within a few months. Most airflow limitations are slow and irreversible. Some patients progress to pulmonary heart disease, respiratory failure. The general patient every 1 to 4 times a year of acute exacerbations or urgency