[Fat embolism of the lungs as the cause of death. Etiology, pathogenesis and reasoning (author's transl)].

A comprehensive survey is given of the most important theories of etiology, pathogenesis and pathophysiology of pulmonary fat embolism. Autopsy and microscopic examinations were performed on 26 corpses with different causes of death. The total contents of fat of the lungs was analyzed by chloroform extraction. Death due to pulmonary fat embolism was diagnosed in three cases. In those with whole fat contents of about 20 g or more the histological degree was equivalent to occlusion of half of all vessels. The histological feature resembled that of shock; hemorrhage and microthrombosis were regular findings. The functional and morphological relationships with shock are discussed. It is concluded that, at least in the initial stage, fat embolism is due to mechanical injury. This mechanism is possibly altered or enhanced by biochemical changes in later phases. Pulmonary fat embolism is a disease which may cause death if mechanical, toxic and shock-inducing effects lead to insufficiency of the cardio-respiratory system. In forensic cases death due to fat embolism should be diagnosed only after exclusion of other lethal factors. Posttraumatic cases often show competition with shock due to hemorrhage. It is important to relate the degree of fat embolism to preexisting diseases.