P.057 A case of cerebral fat embolism in the absence of right-to-left shunt

Abstract

Background: A 64-year-old man underwent an elective right total hip arthroplasty. Post-operatively, his GCS was 6, despite reversal of anesthetic agents. His toes were upgoing bilaterally. He did not have other focal neurologic deficits. He was intubated for airway protection. His only vascular risk factor was hypertension. Methods: [Case Report]Results: A CT/CTA/CTP head was unremarkable. A 1.5T MRI showed a few tiny, bihemispheric, embolic infarcts. These were not significant enough to account for his decreased level of consciousness. His blood work did not show evidence of coagulopathy. A subsequent 3T MRI demonstrated widespread, tiny embolic infarcts in a starfield pattern, consistent with cerebral fat embolism. A transesophageal echocardiogram with bubble study failed to demonstrate a right-to-left shunt. By post-operative day 11, he returned to his neurological baseline. Conclusions: A high degree of suspicion is required to diagnose cerebral fat embolism. There are reports of cerebral fat embolism in the absence of right-to-left shunt. The proposed mechanism is physiologic stress leading to systemic release of free fatty acids and inflammatory mediators, which damage capillary beds and disrupt the blood-brain barrier. This diagnosis has important prognostic implications as fat vacuoles deform easily and deficits are typically more reversible than those occurring with other embolic events.