Fat embolism syndrome and elective knee arthroplasty

To report a case of fat embolism syndrome (FES) following elective left knee arthroplasty and review the diagnosis, investigation, prevention and perioperative management of this condition. A 76-yr-old lady presented for left total knee arthroplasty under general anesthesia. After an uneventful anesthetic and initial recovery, she developed respiratory and neurological complications six hours postoperatively necessitating supportive care in the intensive care unit. Following extensive investigation, a clinical diagnosis of FES was made 48 hr postoperatively supported by the development of diffuse encephalopathy, thrombocytopenia, hypoxemia, chest petechiae and chest x-ray changes. A magnetic resonance imaging scan five days postoperatively confirmed this diagnosis. Her postoperative course showed gradual improvement consistent with a slowly resolving encephalopathy. Previous published cases of FES associated with knee arthroplasty present either with intraoperative cardiorespiratory collapse or, as with this patient, in the postoperative period with respiratory, cardiovascular and/or cerebral dysfunction. The clinical diagnosis of FES is essentially one of exclusion, supported by laboratory and radiological investigations. Preoperative identification of at-risk patients, use of appropriate invasive perioperative monitoring and modified surgical techniques may minimize the development of the syndrome. Treatment is supportive.