Platypnea-orthodeoxia syndrome associated with a thoracic vertebral fracture following a car accident.

Platypnea-orthodeoxia syndrome (POS) is a rare clinical condition defined by the presence of dyspnea and deoxygenation accompanying changing from a supine to an upright position. We experienced the case of a 75-year-old woman who developed severe acute dyspnea after a car accident. Detailed history taking and a physical examination offered important clues that helped to make an accurate diagnosis of POS. The mechanism of onset is unique and rare; however, it is important for clinical cardiologists to keep this possibility in mind when making a differential diagnosis.