Fat embolism syndrome
Fat embolism syndrome is a clinical triad of hypoxemia, neurologic dysfunction, and petechial rash occurring 24 to 72 hours after long-bone or pelvic fracture, treated with supportive oxygen/ventilation and prevented above all by early fracture fixation within 24 hours.
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What this article covers
- Overview
A clinical triad after long-bone trauma: fat embolism syndrome is respiratory insufficiency, neurologic dysfunction, and a petechial rash arising 24 to 72 hours after fracture of a long bone or the…
- Epidemiology
Long-bone and pelvic fracture is the dominant setting: most cases follow femoral shaft or pelvic fracture, particularly comminuted fractures (more than two bone segments) or multiple fractures from…
- Risk factors
Femoral shaft fracture: the single most classic precipitant, particularly comminuted fracture.
- Pathophysiology
Fracture liberates marrow fat and hematopoietic debris: disruption of the bone marrow at the fracture site releases free fatty acids and marrow cellular contents directly into the venous circulation.
- Clinical features
The diagnosis rests on the presence of the triad after a qualifying fracture: respiratory distress, neurologic dysfunction, and a petechial rash occurring 24 to 72 hours after closed or multiple…
- Differential diagnosis
Pulmonary embolism: pleuritic chest pain and hypoxemia after immobilization or surgery, but without the neurologic dysfunction or petechial rash of fat embolism syndrome; CT pulmonary angiography…
- Diagnosis
Fat embolism syndrome is a clinical diagnosis: it is confirmed by the presence of the triad, respiratory distress, neurologic dysfunction, and petechial rash, arising 24 to 72 hours after closed or…
- Management
First, provide supplemental oxygen titrated to maintain adequate saturation: escalate to high-flow nasal cannula or noninvasive ventilation if hypoxemia worsens.
- Complications
Acute respiratory distress syndrome and respiratory failure: the most immediately life-threatening complication, occasionally requiring prolonged mechanical ventilation.
- Prognosis
Most patients recover spontaneously and completely with supportive care: the syndrome is typically self-limited once the source fracture is stabilized.
- Prevention
Early surgical fixation of long-bone and pelvic fractures, ideally within 24 hours of injury: open reduction and internal fixation reduces the incidence of fat embolism syndrome compared with delayed stabilization.
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