A trauma evaluation requires a complete and thorough examination beyond the ABCs of resuscitation. Secondary assessment includes careful examination of distal pulses. Absent lower extremity pulses could indicate aortic injury, vascular trauma from an adjacent fracture, or extremity compartment syndrome.

Patients with blunt aortic injury may show signs such as upper extremity hypertension, diminished femoral pulses (“pseudocoarctation”), and an intrascapular murmur. The presence of all three are distinctly uncommon, and diminished femoral pulses in a patient with history of blunt chest trauma or motor vehicle accident should always alert one to think of hidden aortic injury. Dissection should be suspected in any patient with a widened mediastinum on chest radiograph although a normal x-ray does not rule out an injury. Further imaging for dissection includes computed tomography scan or transesophageal echocardiogram.

Blunt aortic injury as part of blunt chest trauma, is responsible for 10% to 15% of motor vehicle-related deaths. It is a lethal injury that provides the surgeon with a small window of opportunity for effective surgical intervention. This window is often missed because the injury may be asymptomatic initially, followed later by catastrophic bleeding or other complications. In more than half the cases, the involved aortic segment is the proximal descending aorta just distal to the origin of the left subclavian artery. Less common is involvement of the aortic arch, the distal thoracic aorta at the diaphragm, or multiple sites.