A 25-year-old man sustains a closed femoral shaft fracture. Forty-eight hours after intramedullary nailing he develops tachypnoea, confusion, hypoxia with PaO2 of 55 mmHg, and a petechial rash over the chest and axillae. The most likely diagnosis is:
- A Pulmonary thromboembolism
- B Fat embolism syndrome ✓
- C Transfusion-related acute lung injury
- D Hospital-acquired pneumonia
Correct answer: B. Fat embolism syndrome
Explanation
Fat embolism syndrome typically appears 24 to 72 hours after a long bone fracture or its instrumentation, with the classic triad of respiratory distress, cerebral involvement, and a petechial rash in a non-dependent distribution such as the chest and axillae. Thromboembolism usually occurs later and does not produce petechiae, which distinguishes it from this presentation.
Reference: Apley's System of Orthopaedics and Fractures, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.