Airways disease: evolution, pathology, and recognition.

Obstruction to airflow in the lung was studied in 150 patients who presented with coin lesions necessitating surgical resection of the lung. Pulmonary function tests were performed before surgery, and the structure of the lung or lobe was analysed by means of morphometric techniques. The evolution of obstructive airways disease appeared to be based on a progressive chronic inflammatory reaction in the respiratory and membranous bronchioles. This led to progressive airway obstruction and was associated with destruction of the lung surface. The early pulmonary vascular problems appeared to be related to progressive airways obstruction that may have increased pulmonary artery pressure by causing alveolar pressure to increase more than pleural pressure during the hyperventilation of exercise.