Segmental collapse in therapeutic pneumothorax.

Abstract

The basic rationale of collapse therapy in pulmonary tuberculosis is the clinical observation that a massive pleural effusion which is superimposed on a severe pulmonary lesion generally brings about general improvement. Although tried by others, pneumothorax was first systematically applied by Forlanini. He and his co-workers, as well as subsequent investigators, believed that a diseased lung immobilized by maintaining a pneumothorax with markedly positive pressure would heal because of functional rest. In the development of pneumothorax treatment, there was one further important step, namely, the recognition by Ascoli (1) in 1912, that partial pulmonary collapse by subatmospheric intrapleural pressures, “hypotensive pneumothorax,” produced better results. At approximately the same time Parry Morgan (2) reported some experimental work' on the pathogenesis of selective collapse and probably was the first to start the controversy regarding “elastic recoil of the lung.” Some years later Barlow and Kramer (3) coined the phrase “selective collapse,” describing their technic for achieving collapse of the diseased lobe. Further studies indicated that selective collapse was achieved without any special attempt on the part of the therapist other than maintaining a relatively negative pressure in the intrapleural space. The mechanism by which selective collapse was achieved, received and continues to merit some discussion. Of all the investigations reported in the literature, the most noteworthy have been those of Coryllos (4), whose critical studies on the role of bronchial obstruction have been quite generally accepted. Working especially in an investigation of the localization of lung abscess, Kramer and Glass (5) were the first to describe the bronchopulmonary segment and to project its anatomical unit to the chest wall. Further studies, especially for the purpose of resection, have been recorded by Brock (6), Foster-Carter (7), and others. It is our belief that tuberculosis is essentially a segmental and sub-segmental pathological process. It has been amply demonstrated by Meissner (8), Silverman (9), and others interested in tracheobronchial tuberculosis that the most frequent lesion occurs in the finer bronchial ramifications. If a tuberculous lesion is present in a segment or sub-segment, the branch bronchus is usually involved in the same process. At the very least these bronchi are edematous, have little or no ciliary movement, and are partially filled with caseous material, desquamated mucosal epithelium, and other detritus. With the institution of pneumothorax, the normal lengthenin.g and shortening and dilatation and contraction of the bronchial tree are reduced, again tending to collapse of the segment or a division thereof. If then the damage in the branch bronchus or bronchi is accepted as an inevitable concomitant of the disease, it is but a short step to understand the mechanics of segmental or lobular collapse.