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Aortic injury should be suspected when there are severe deceleration
forces; classic physical examination findings may not be present.
Chest radiography is sensitive for the presence of aortic injury and
should be followed by CT angiography when concerning.
Aggressive resuscitation and immediate surgical intervention are
necessary for patients with aortic or great vessel injuries and signs of
circulatory compromise such as tachycardia, poor perfusion, or
hypotension.

Current Evidence
Life-threatening injuries to the great vessels of the thorax carry a high mortality
rate but are fortunately rare. The aorta is the vessel most commonly involved in
both blunt and penetrating trauma. Rupture of the aorta occurs in approximately
10% to 30% of adults sustaining severe blunt trauma but is much less common in
the pediatric population, affecting less than 1% of all children with blunt thoracic
trauma. Early detection of such injuries is vital for survival, as overall mortality
rate of aortic rupture in children is 75% to 95%, with most deaths occurring at the
scene.

Clinical Considerations
Clinical Recognition
Aortic injuries are most frequently associated with high-energy deceleration
forces, commonly from automobile collisions, causing a shearing stress. The
descending aorta is fixed and the arch is mobile. With deceleration, shearing takes
place at the level of the ligamentum arteriosum, the most superior fixation point
and the most common site of aortic tears in adults and children.
When a great vessel ruptures, massive blood loss may ensue. The body’s
compensatory mechanisms for the blood loss include an increase in both heart
rate and total peripheral vascular resistance. Relying solely on a decrease in
systemic blood pressure to detect hemorrhage in children may be deceiving
because children may lose 25% or more of their total blood volume before their

systemic blood pressure is affected. Children with significant bleeding may have
a normal systolic blood pressure but be tachycardic and poorly perfused with a
prolonged capillary refill time. These findings should trigger aggressive
resuscitation and urgent investigation of the source of hemorrhage prior to the
onset of hypotension.