[Animal experiments on particulars of the time factor in the development and solving of pulmonary atelectasis caused...

In literature are only older publications about the temporal beginning of the acute atelectasis after obstructive foreign body occlusion of the bronchial system which are operated at the open thorax. For this reason experiments on animals were made to find out the earliest beginning of an atelectasis by a simple bronchial occlusion as an imitation of a natural process of a foreign body aspiration. The alterations in each single phase of development showed regularly based on serial radiographies and by the autopsy macroscopic and microscopic that about 2 or 3 h after aspiration of an obstructive foreign body it will be reckoned with a complete atelectasis. Only now correlate the clinical result, the X-ray and the pathological-anatomical alterations. The histological picture of the complete atelectasis follows the macroscopic result only in longer temporal distance. Atelectasis occuring before the mentioned moment cannot be explained by an absorption of air from the alveolar tissue, but they depend on foreign body independent reflexes (= reflex contraction atelectasis). In other series of experiments the retroplasia of an atelectasis showed no regularity after the release of the bronchial occlusion, as the time of development, but it is possible to say that it takes more time of retroplasia the longer the atelectasis lasts. Dependent on that the respiratory exchange was jerky into the atelectatic lung after a resting period without prefering any lobes of lungs where localised atelectatic foci remain a longer time.