Two days after conservative treatment of a closed fracture of the femoral shaft, a young man becomes acutely breathless and confused. He has tachypnoea, hypoxia and a petechial rash over the anterior chest wall and axillae. The most likely diagnosis is:
- A Pulmonary thromboembolism from deep vein thrombosis
- B Anaphylactic reaction to analgesics
- C Fat embolism syndrome ✓
- D Aspiration pneumonitis
Correct answer: C. Fat embolism syndrome
Explanation
Fat embolism syndrome complicates long bone fractures, typically 24 to 72 hours after injury, with the classic triad of respiratory distress, neurological disturbance and a petechial rash over the chest, axillae and conjunctivae. Fat globules from the marrow enter torn veins and lodge in pulmonary and systemic capillaries. Thromboembolism usually occurs later than 72 hours and does not cause petechiae, which makes option A the key distractor to reject.
Reference: Bailey and Love's Short Practice of Surgery, 27th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.