summary Fat Embolism Syndrome is an acute respiratory disorder caused by an inflammatory response to embolized fat globules that may enter the bloodstream as a result of acute long bone fractures or intramedullary instrumentation. Patients present with hypoxia, changes in mental status, and petechial rash. Diagnosis is made clinically with presence of hypoxemia (PaO2 < 60), CNS depression, petechial rash, and pulmonary edema. Treatment is focused on prevention with early stabilization of long bone fractures. Mechanical ventilation with high levels of PEEP is the recommended treatment for acute presentation. Epidemiology Incidence 3-4% with isolated long bone trauma 10-15% with polytrauma Etiology Pathophysiology fat and marrow elements are embolized into the bloodstream during acute long bone fractures intramedullary instrumentation login to view 2 more bullets pathophysiology two theories regarding the causes of fat embolism include login to view 4 more bullets Diagnosis Criteria Major (1) hypoxemia (PaO2 < 60) CNS depression (changes in mental status) petechial rash pulmonary edema Minor (4) tachycardia pyrexia retinal emboli fat in urine or sputum thrombocytopenia decreased HCT Additional PCO2 > 55 pH < 7.3 RR > 35 dyspnea anxiety Presentation History symptoms usually present within 24 hours of inciting event Symptoms patient complains of feeling "short of breath" patient appears confused Physical exam tachycardia tachypnea petechiae axillary region conjunctivae oral mucosa Studies ABG hypoxemia (PaO2 < 60 mmHg) Treatment Nonoperative mechanical ventilation with high levels of PEEP (positive end expiratory pressure) indications login to view 1 more bullet Prevention early fracture stabilization indications login to view 1 more bullet techniques to reduce the risk of fat emboli login to view 3 more bullets Prognosis Fatal in up to 15% of patients