PATHOPHYSIOLOGY OF OBSTRUCTIVE AIRWAYS DISEASE

Chronic obstructive pulmonary disease is a group of disorders that hav e in common abnormal airway structure that results in obstruction to a ir-flow. In emphysema, obstruction is thought to be due to the loss of normal elastic tension in the lung parenchyma. Cigarette smoke is the most important cause of emphysema. Injurious agents, either in the ga s or particulate phase, incite a proteolytic reaction in the lung. The type of emphysema and its topographic distribution in the lung stem f rom normal physiologic processes that concentrate the cigarette puff b oth within the lung and within the secondary pulmonary lobule.