[Experimental study of the effect of membrane oxygenators on the pulmonary structure of the dog and monkey (author's transl)].

Six dogs and 5 monkeys were subject to extracorporeal circulations with membrane oxygenators for various time periods (from 4 to 57 hours). The pulmonary samples, examined with electron microscopy, enabled us to control the appearance of lesions (similar for the two animal species) and to follow their evolution. From the second hour, abnormalities of the capillary endothelium were observed; but at the 6th hour, the lesions had already deeply affected the whole pulmonary structure and became more and more serious. This intrinsic toxicity of membrane oxygenators on the pulmonary structure should incite extreme caution in the use of this method in man.