The Cognitive Effects of Fat Embolus Syndrome Following an Isolated Femoral Shaft Fracture

Abstract

Documented neurological features of fat embolus syndrome and acute respiratory distress syndrome following trauma include acute confusion, headache, lethargy, irritability, seizure, stroke, and coma. These are thought to result from cerebral embolization and secondary hypoxemia1,2. The long-term cognitive effects in patients who recover from fat embolus syndrome are unclear. We present the case of a patient who recovered after the development of fat embolus syndrome following an isolated femoral diaphyseal fracture. Comprehensive neuropsychological testing revealed appreciable and persistent cognitive dysfunction eighteen months after the initial insult. Our patient was informed that data concerning the case would be submitted for publication. Atwenty-three-year-old female analytical chemist, educated to a degree level (Bachelor of Science), with no previous medical complaints, sustained an isolated transverse fracture of the right femoral diaphysis with no associated chest injury after a soccer tackle. At the time of admission, the oxygen saturation level on room air was normal at 98%. Longitudinal skin traction was applied in the emergency department to stabilize the fracture in preparation for intramedullary fixation. Six hours after admission, acute dyspnea and tachycardia developed, and the patient became transiently unresponsive. Oxygen saturation fell to 84% on maximum oxygen therapy. She was transferred to the intensive care unit, where the partial tension of arterial oxygen (PaO2) was measured at 8.3 kPa with an inspired oxygen fraction (FiO2) of 0.6, resulting in a PaO2/FiO2 ratio of 13.8. The diagnostic criteria for both acute respiratory distress syndrome and fat embolus syndrome were fulfilled3. The patient was intubated and required positive airway pressure ventilation to maintain an appropriate level of arterial oxygen saturation. The patient's respiratory status appeared to be well controlled with this ventilatory support, and the arterial oxygen concentration was >10 kPa. Eighteen hours after admission, …