The Pre-brief
Trauma remains the leading cause of death and disability in the United States in patients under 44 years old. Imagine, however, providing excellent care to your multi-trauma patient, only for them to suffer debilitating disability like a stroke from a missed pathology.
Blunt cerebrovascular injury (BCVI) is such a pathology.
What is it?
Remember the anatomy of the brain’s cerebrovascular system? There are two parts – anterior (supplied by the carotid arteries) and posterior (supplied by the vertebral arteries), and they are connected through the Circle of Willis. Around the area of the cervical spine and base of the skull, these vessels are at particular risk of damage from various injury mechanisms. The internal carotid and vertebral arteries are the most prone to damage. This injury is termed BCVI.
How common is BCVI, and what’s at stake?
Overall, BCVI is less common, accounting for about 1-3% of all blunt trauma admitted to trauma centers. It was notoriously under-diagnosed and still requires active decision making on the part of the clinician to find it. A missed BCVI is associated with an overall mortality of 23-28%, with anywhere from 48-58% of those who survive having some form of permanent neurologic disability.
Early suspicion is critical – remember that the average time from injury to stroke ranges from 12-75 hours.
Here are the outcomes:
Vessel affected | Stroke risk | Mortality | Severity dependent on grade? |
Internal carotid artery | 26-41% | 13-21% | Yes |
Vertebral artery | 14-24% | 4-8% | No |
When should you suspect this?
A variety of clinical findings and injury mechanisms put your trauma patient at risk of BCVI. Note that a cervical spine fracture has the highest association with BCVI (odds ratio of 5.45, 95% CI 2.24-13.27). 63% of people will have no clinical signs of stroke on presentation.
| Injury Patterns Signifying High Risk | Clinical Findings Signifying High Risk |
Complex facial fractures (LeFort II and III) Basilar skull fracture (especially if involving the carotid canal) Complex skull fracture Diffuse axonal injury/TBI with GCS <6 Mandibular fracture Cervical hyperextension/rotation/flexion injury Any level of cervical spinal injury (fracture/subluxation/ligamentous) – in particular at levels C1-C3 Near-hanging with anoxic brain injury Neck soft tissue injury, e.g. the seatbelt sign Upper rib fractures or significant thoracic injury | Arterial bleeding or expanding hematoma from the head and neck Focal neurologic deficits e.g. limb weakness Cervical bruit (especially if age <50 years) Neurologic exam not consistent with CT findings Horner’s syndrome (miosis, ptosis, and anhidrosis) Stroke on follow-up neuroimaging |
How do I grade BCVI?
| Grade | Injury | Carotid Artery Stroke Risk | Vertebral Artery Stroke Risk |
| I | Intimal irregularity or dissection <25% luminal narrowing | 3% | 6% |
| II | Dissection or intraluminal hematoma with ≥25% luminal narrowing, intraluminal thrombus, or visible intimal flap | 14% | 38% |
| III | Pseudoaneurysm | 26% | 27% |
| IV | Vessel occlusion | 50% | 28% |
| V | Vessel transection with free extravasation | 100% | 100% |
I suspected it, and I found it – now what?
Treatment options vary depending on grade and site of injury, ranging from initiation of anti-platelet agents such as aspirin to stent placement, or operative intervention. The associated injuries need to be considered before deciding on a therapy. Close consultation should occur with trauma and neurosurgical services.
The Debrief
- Suspect BCVI in your blunt multi-trauma patients, as missing this injury carries significant risk of stroke and/or mortality
- Complex head, neck, and thoracic injuries should raise your suspicion for this injury
- Add a CTA of the neck to screen for BCVI in addition to other indicated imaging
- Early consultation with trauma and neurosurgical services allows tailored treatment
References
Biffl WL, Moore EE, Ryu RK, et al. The unrecognized epidemic of blunt carotid arterial injuries: early diagnosis improves neurologic outcome. Ann Surg 1998;228(4):462-470 PMID: 9790336
Burlew CC, Biffl WL, Moore EE et al. Blunt cerebrovascular injuries: redefining screening criteria in the era of noninvasive diagnosis. J Trauma Acute Care Surg 2012;72(2):330-335 PMID: 22327974
Grigorian A, Kabutey N-K, Schubl S, et al. Blunt cerebrovascular injury incidence, stroke-rate, and mortality with the expanded Denver criteria. Surgery 2018;164(3):494-499 PMID: 29884478
