肺气肿是由于终本细支气管远端的气道弹性减退、充气过度并伴有气道损害的病理状态。按其形成原因和病变部位分主要有以下几种类型。l阻塞性问气肿：是发生率较高、危害性最大的一种肺气肿。多因支气管的慢性炎症，使支气管粘膜充血、水肿、管腔变窄，造成不完全性活瓣样阻塞， Emphysema is due to the end of the bronchiole distal end of the airway elasticity decline, over-inflated and accompanied by airway damage pathological state. According to the formation of the reasons and the main part of the following types of lesions. l obstructive asked emphysema: is a higher incidence of the most harmful kind of emphysema. More due to chronic bronchitis, bronchial mucosa congestion, edema, narrowing of the lumen, resulting in incomplete valve-like obstruction,