Fat Embolus Syndrome

Snapshot

• A 60-year-old man presents to the emergency room after a motor vehicle accident. He is found to have a femur fracture on the right. He is admitted into the hospital to correct the fracture and observation. Two days after hospitalization, he develops sudden shortness of breath, followed by confusion, which is far from baseline according to his family. A petechial rash is noted on his chest.

Introduction

• Fat embolism syndrome results from fat emboli often associated with long bone fractures
• Occurs around 1-3 days after instigating event
• Pathogenesis – not completely elucidated 
  • globules of fat escape bone marrow-rich areas (long bones, pelvis) after trauma 
  • clogs up vessels
• Associated conditions/risk factors
  • trauma
  • long bone fracture
  • pelvic fractures
  • liposuction
  • CPR
• Classic triad
  • hypoxemia
  • neurological abnormalities
• petechial rash

Presentation

• Symptoms
  • acute shortness of breath
    • occlusion of pulmonary vessels
  • petechiae in neck, chest, and axilla
    • occlusion of dermal capillaries by fat emboli
  • altered mental status
    • occlusion of neurological vessels
    • confusion
    • seizures
    • focal deficits
• typically fully reversible

Evaluation

• Diagnosis by clinical history and exam
• Biopsy if clinical diagnosis is unclear 

Differential Diagnosis

• ARDS 
• Acute lung injury

Treatment

• Supportive care
• Corticosteroids may be beneficial in life-threatening cases
• limited evidence

Prognosis, Prevention, and Complications

• Prognosis
  • most patients recover without any sequelae