Pulmonary Emphysema

Abstract

A review of the recent literature on pulmonary emphysema seems appro priate at the present time, at which there has been an increasing interest in this disease. In part this is a reflection of the general emphasis on diseases affecting the older age groups and in part it is a result of the recent surge of interest in pulmonary physiology on the part of clinicians. The pathology of pulmonary emphysema is uninspiring and the roentgenologic appearance of the lungs is not dramatic. The disease does produce many alterations in the physiology of the lungs and for this reason investigation of this aspect of the disease has been most fruitful.The description of pulmonary emphysema by Laennec (1), which still stands as a model of writing on clinical subjects, should be read by anyone interested in the disease. Excellent reviews have been written by Kountz & Alexander (2) and by Christie (3). PATHOLOGYThere have been relatively few recent contributions to the pathology of pulmonary emphysema. Hartcroft (4) has made a major contribution to the understanding of the microscopic anatomy of the disease. He points out the need for the fixation of the lungs in an inflated state and for the consideration of the alveoli as three-dimensional structures. The alveoli are arranged about the alveolar duct as open stalls are related to the central passage of a barn. In emphysema the alveoli are increased in diameter and decreased in depth. The alveolar duct is increased in size. The appearance of rupture of the alveolar walls is an artifact resulting from the plane of the section passing through the mouths of the alveoli.There have also been studies of the bronchioles and vascular tree in pulmonary emphysema. One of the characteristic features of emphysema is increased resistance to air flow in the bronchial tree. Spain & Kaufman (5) made a careful study of the bronchioles in pulmonary emphysema. They found the walls of the terminal bronchioles to be thickened. The walls showed fibrosis and often inflammatory cell infiltration. The authors believe that these changes in the bronchioles are primary and that the changes in the alveoli are secondary to bronchiolar obstruction. Cudkowicz & Armstrong (6) described narrowing and obliteration of the intrapulmonary bronchial arteries in pulmonary emphysema. This resulted from medial hyperplasia and intimal thickening. Anastomoses between the bronchial and pulmonary 1 The survey of the literature pertaining to this review was completed in March, 1955. 123 Annu. Rev. Med. 1956.7:123-140. Downloaded from www.annualreviews.org Access provided by Lancaster University -UK on 02/05/15. For personal use only. Quick links to online content Further ANNUAL REVIEWS

Respiratory System

“…Special mention should therefore be made of a new publication from the Rochester group (164), which aims at presenting accumtilated knowledge and new data on the complexities of gas exchange in the body in a fashion serving to bring closer the extremes. Rossier, Biihlmann & Wiesinger have written a comprehensive book on the physiology and pathophysiology of respiration (173), while interest was concentrated on the changes involved in pulmonary emphysema in a review by Ebert (66). An introduc tion into the study of respiratory function is given by Cara (31), while clinical aspects of the respiratory system and various functional tests are reviewed by Christie & Bates (38).…”