Blunt cerebrovascular injuries: does treatment always matter?

Background: Blunt cerebrovascular injuries (BCVI) have become an increasingly recognized entity. Stroke as a result of these injuries can have devastating consequences. Optimal screening criteria, diagnostic imaging, and therapy for BCVIs have not been elucidated. Our institution began to apply liberal screening criteria using a whole-body scanning protocol with multidetector computed tomographic (WB-MDCT) scans to diagnose these injuries. The purpose of this study is to describe a single institution's large experience in patients with BCVI in an effort to provide insight into the diagnosis and management of these injuries.

Methods: All patients with a BCVI admitted to the R Adams Cowley Shock Trauma Center during a 30-month period were included in this study. Choice of diagnostic evaluation and treatment regimens were at the discretion of the treating attending physician. Review of medical records and all relevant radiographic studies were retrospectively performed for the purposes of this study.

Results: During the study period, there were 12,667 patients admitted to the R Adams Cowley Shock Trauma Center. There were 147 patients identified with 200 carotid or vertebral artery injuries. The incidence of BVCI was 1.2%. Mortality was 13%. Anatomic injury risk factors for BCVI (major facial fractures, skull base fractures, cervical spine fractures or spinal cord injury, or traumatic brain injury) were found in only 78%. Major thoracic injury was found in 63% of patients with carotid artery injuries and cervical spine fractures or spinal cord injury was found in 74% of patients with vertebral artery injuries. The initial screening test employed was a WB-MDCT in 96% of patients of which 84% detected a BCVI. Treatments included endovascular therapy (22%), antiplatelet medications (36%), anticoagulation (10%), and combination therapy with antiplatelet agents and anticoagulation (18%). Thirty percent received no therapy, primarily due to contraindications from concomitant injuries. There were 18 (12%) patients who had a stroke. Of these patients, 8 (44%) had evidence of infarction at admission, 6 were diagnosed within 72 hours, and 4 were diagnosed after 1 week. Stroke-related mortality was 50%, whereas clinical follow-up after hospital discharge demonstrated only one patient with disability as a result of infarction. Of 10 patients who did not have stroke at admission, 3 were fully treated, 5 had specific contraindications to therapy, and 2 had no or false-negative imaging before infarction. Stroke rates for untreated patients were 25.8% and patients treated with any therapy had a stroke rate of 3.9% (p = 0.0003). Radiographic follow-up >1 month after injury demonstrated improvement in over 50% of patients.

Conclusions: BCVIs are not infrequent after blunt trauma. These injuries occur even in the absence of classically described risk factors. Liberal screening with WB-MDCT incorporates detection of these injuries into the initial diagnostic evaluation. Stroke occurs in a substantial number of patients and carries a very high mortality. However, nearly one third of patients with BCVI are not candidates for therapy. Treatment does reduce the risk of infarction in patients with BCVI, but strokes, when they occur, are not preventable.