Uremic lung lesions as a form of chronic edema.

Biochemical uremia lasting two weeks was developed in five dogs. It appeared light and electron microscopically that the uremic pulmonary lesions consisted in atelectasis and edema and were more advanced in the inferior paravertebral and parahilar parts of the lung. On the basis of electron microscopic findings it could be assumed that the peripheral respiratory segments (alveolar saccules) are the first to be involved in the process. In partially aerated alveolar ducts condensed edema fluid was found on the surface of recently produced edema fluid of low electron density. This condensed layer seems to originate from more peripheral segments and to be pushed passively upwards. Such processes can be interpreted as a preliminary stage of hyaline membrane formation in experimental uremia.