The natural history of clinically occult arterial injuries: a prospective evaluation.

Nineteen patients with 20 clinically occult arterial injuries were prospectively followed without surgery in order to define the natural history of these lesions. The patients were predominantly male (74%), with a mean age of 31 years. The mechanism of injury was penetrating in 13 cases and blunt in seven cases. The arterial injuries were located in the lower extremity (45%), upper extremity (35%), neck (15%), and abdominal aorta (5%). Neurologic trauma (55%) and musculoskeletal trauma (40%) were the most common associated injuries. There was no clinical manifestation of vascular injury in any case. All lesions were identified by arteriography, which was performed for high-risk blunt trauma and proximity of penetrating wounds to major vessels. Intimal flap was the most commonly demonstrated form of injury (65%), followed by focal narrowing (30%) and false aneurysm (5%). Followup of 19 injuries (95%) was obtained for periods ranging from 3 days to 19 months (mean, 3.8 months). Arteriographic followup was obtained in 15 cases (79%). One injury (5%), a false aneurysm, enlarged after 10 weeks and was surgically repaired without clinical sequelae. All other lesions either resolved (53%), improved (16%), or remained unchanged (26%). These results suggest that nonoperative observation may be a safe and feasible method of managing clinically occult arterial injuries.