This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: FMGE 2019, Subject name: Surgery
40 years old patient with femur fracture with pulmonary infiltration and respiratory distress 
Select and explain. 
A. Fat embolism, B. Pulmonary embolism, C. Air embolism, D. Obstruction
A: Fat embolism
Answer: A: Fat embolism 
Explanation: Fat embolism Patient presenting long bone fractures + respiratory distress +petechiae / hemorrhage in brain suggests: fat embolism syndrome Generally associated with displaced long bone fractures of lower extremities Fat embolism will reach in the brain through a right to left cardiac shunt or through an intact pulmonary circulation in the patient without the shunt Major clinical characteristics: respiratory insufficiency, neurologic symptoms, and petechial skin rash