Broncho-pneumologie最新文献

The thickness and composition of the walls of nonrespiratory bronchioles were quantitatively assessed in groups of normal and emphysematous lungs. In both the groups there was a gradual increase in the thickness of the walls of nonrespiratory bronchiles with increasing caliber, but this change was not proportionate. Smaller bronchioles possessed thicker walls in both the groups. Bronchioles of comparable internal diameter were also found to be slightly thicker than normal in emphysematous specimens at all levels of caliber. Through a system of schematic models, it was shown that the relatively thicker walls of smaller bronchiles in normal and emphysematous lungs would enhance airflow in the proper direction both during expiration and inspiration. The slightly thicker walls of bronchioles in emphysema would result in their closure at substantially higher lung volumes than would occur with the somewhat thinner walled bronchioles of corresponding diameters in normal lungs. Although such thickening might only be focal in emphysema, this would interfere with expiratory airflow and result in air-trapping. This investigation failed to demonstrate differences in the composition in the walls of nonrespiratory bronchioles of normal and emphysematous lungs.

Postmortem studies of the total lung airways resistance (Rt), the central airways resistance (Rc), and the peripheral airways resistance (Rp) had been performed on normal lungs, on lungs with emphysema and lungs from patients with chronic obstructive pulmonary disease (COPD). In the normal lung a significant relationship between age and Rt was found. A decrease between 20 and 40 yr of age resulted from a decrease of Rp whereas an increase of Rt above the age of 40 was related to an increase in Rp. In the lungs with emphysema and obstruction Rp was increased especially. By variations of the breathing frequency and the lung volume (% of vital capacity) it could be detected that a remarkable effect upon Rt was caused by Rp. In general we found that even in normal lungs Rp is much higher than previously thought.

Small non-respiratory bronchi of lungs of patients suffering from slight and severe centrilobular emphysema of city dwellers and from focal dust emphysema, has been studied, by means of serial sections assessing the importance of the connective tissue proliferation in relation to the cross-sectional morphology of the bronchus, its diameter and longitudinal profile. Camera lucida drawings of parietal muscle and reconstructions of the bronchial wall and lumen were done. A positive relationship between the amount of the connective tissue proliferation, the severity of emphysema and the changes in the parameters indicated was found. The repercussion of fibrosis in the small airways disease of centrilobular emphysema, can be summarized as follows: the production of areas of localized stenosis, the contribution to the development of bronchiolar deformities, the obliteration of some airways and the alteration of bronchial muscle. It can be concluded, therefore, that the fibrosis, as second main cause of small airways obstruction, has a more wide repercussion on the bronchiolar structure than that of alveolar loss, and that it can probably affects not only the "static" characteristics of the bronchial wall, but also their "dynamic" behaviour by means of disorganization of the muscle.