The three syndromes of fat embolism: pulmonary manifestations.

The clinical course and radiographs of 30 patients with fat embolism syndrome were reviewed. In all cases the classic triad of neurologic dysfunction, respiratory insufficiency, and petechiae were present. Three responses to embolized fat were noted. The hyperacute response was seen in two patients with paradoxical embolization of fat to the systemic circulation. A "classic response" was noted in 18 patients with transient respiratory compromise and variable radiographic findings. The two deaths in the group responding in the classical manner were attributed to massive pulmonary emboli. The third response, noted in ten patients, consisted of a chest radiograph compatible with pulmonary edema in the clinical setting of the adult respiratory distress syndrome. In this group the degree of respiratory dysfunction and pulmonary damage correlated with the development of disseminated intravascular coagulation. Pathologic correlations are presented and the mechanisms by which embolic fat produces tissue damage are discussed.