Carotid artery dissection and motor vehicle trauma: patient demographics, associated injuries and impact of treatment on cost and length of stay.
Jared E. Kray, Viktor Y. Dombrovskiy, Todd R. Vogel
BMC Emergency Medicine 2016;16:23 DOI 10.1186/s12873-016-0088-z
JACO Editorial Reviewer: Steven G. Yeomans, DC, FACO
Published: March 2017
Journal of the Academy of Chiropractic Orthopedists
March 2017, Volume 14, Issue 1
The original article copyright belongs to the original publisher. This review is available from: http://www.dcorthoacademy.com © 2017 Yeomans and the Academy of Chiropractic Orthopedists. This is an Open Access article which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Background: Blunt carotid arterial injury (BCI) is a rare injury associated with motor vehicle collision (MVC). There are few population based analyses evaluating carotid injury associated with blunt trauma and their associated injuries as well as outcomes.
Methods: The Nationwide Inpatient Sample (NIS) 2003–2010 data was queried to identify patients after MVC who had documented BCI during their hospitalizations utilizing ICD-9-CM codes. Demographics, associated injuries, interventions performed, length of stay, and cost were evaluated.
Results: 1,686,867 patients were estimated having sustained MVC; 1,168 BCI were estimated. No patients with BCI had open repair, 4.24% had a carotid artery stent (CAS), and 95.76% of patients had no operative intervention. Age groups associated with BCI were: 18–24 (27.8%), 47–60 (22.3%), 35–46 (20.6%), 25–34 (19.1%), >61 (10.2%). Associated injuries included long bone fractures (28.5%), stroke and intracranial hemorrhage (28.5%), cranial injuries (25.6%), thoracic injuries (23.6%), cervical fractures (21.8%), facial fractures (19.9%), skull fractures (18.8%), pelvic fractures (18.5%), hepatic (13.3%) and splenic (9.2%) injuries. Complications included respiratory (44.2%), bleeding (16.1%), urinary tract infections (8.9%), and sepsis (4.9%). Overall mortality was 14.1% without differences with regard to intervention (18.5% vs. 13.9%; P = 0.36). Stroke and intracranial hemorrhage was associated with a 2.7 times greater risk of mortality. Mean length of stay for patients with BCI undergoing stenting compared to no intervention were similar (13.1 days vs. 15.9 days) but had a greater mean cost ($83,030 vs. $63,200, p = 0.3).
Conclusions: BCI is a rare injury associated with MVC, most frequently reported in younger patients. Frequently associated injuries were long bone fractures, stroke and intracranial hemorrhage, thoracic injuries, and pelvic fractures which are likely associated with the force/mechanism of injury. The majority of patients were treated without intervention, but when CAS was utilized, it did not impact mortality and trended toward increased costs.
Clinical Relevance: This large population study suggests that BCI is rare and appears to require significant trauma in MVC to occur. When BCI is present, other significant trauma is likely to occur simultaneously. The majority of BCI (95.76%) did not require surgery, none required open repair while 4.24% required CAS, and intracranial hemorrhage and stroke was associated with a 2.7 times greater risk of mortality.
JACO Editorial Summary:
- The article was written by authors from the Division of Vascular Surgery, University of Missouri, School of Medicine, Columbia, MO.
- The purpose of the study was to investigate the rare condition of blunt carotid arterial injury (BCI) associated with blunt trauma with MVC using a population based approach considering the associated injuries and outcomes.
- The authors reviewed records between 2003-2010 using ICD-9-CM codes and identified 1, 686,867 MVC patients of which 1,168 patients had documented BCI. These patients were evaluated for demographics, associated injuries, interventions performed, length of stay, and costs.
- Few population based analyses exist for blunt trauma to the carotid artery resulting in dissection. Given the large disproportionate difference between occurrence rates of ischemic strokes comparing the general population (20% in patients <45 years old) vs. those from blunt trauma in MVC (<2%), this study is important.
- Results showed the age group of 18-24 had the highest frequency of BCI.
- Associated injuries included long bone fractures (28.5%), stroke and intracranial hemorrhage (28.5%), cranial injuries (25.6%), thoracic injuries (23.6%), cervical fractures (21.8%), facial fractures (19.9%), skull fractures (18.8%), pelvic fractures (18.5%), hepatic injuries (13.3%), and splenic injuries (0.2%).
- BCI associated complications included respiratory (44.2%), bleeding (16.1%), urinary tract infections (8.9%), and sepsis (4.9%). Overall mortality following BCI was 14.1% with no significant difference in mortality between those with versus those without intervention (stenting).
- Stroke and intracranial hemorrhage was independently associated with a 2.7 times greater risk of mortality. The mean length of stay for patients with BCI was similar comparing those undergoing stenting compared to those with no carotid artery intervention.
- This study points out that BCI occurred more frequently in younger patients, was associated with long bone fractures, thoracic injuries, and pelvic fractures. This suggests that the mechanism of injury is more important than the anatomic location of injury. Also, the study points out that carotid artery stenting was not associated with improved mortality and, it carried an increase in total costs.
- Appropriate early identification of BCI and appropriate treatment were reported as important to reduce the risk of stroke. Utilizing the Denver or Memphis screening criteria, those meeting the criteria were further evaluated with CT angiography in order to identify BCI early which was previously reported to reduce the risk of complications.
- BCI typically starts with an initial tear of the intima and when subendothelial collagen is exposed, it acts as a thrombogenic agent which starts the cascade of platelet aggregation resulting in a thrombus formation.
- Because it is well known that there is a latent period ranging between hours and days during which neurological deficits may manifest, most patients initially have no overt neurological deficits.
- The mechanism of injury (rapid deceleration, hyperextension and/or severe flexion with rotation of the neck) and the presence of long bone fractures, thoracic injuries, pelvic fractures, cervical fractures, facial fractures and skull fractures should raise suspicion of BCI.
- While there is currently no standard treatment algorithm, it is generally accepted that interventional carotid artery stenting is not initiated until dissection has progressed to pseudoaneurysm or in the event of a rapid progression of the disease resulting in hemodynamic instability increasing risk for arterial occlusion or transection.
- Utilizing the Denver grading scale, most recent evidence suggests only grade II and III injuries be considered for endovascular stenting. Routine stenting is believed to add risk of stroke without any added benefit and this study reported an obvious increase in cost without improved outcomes.
- Optimal treatment for BCI remains unclear. Antithrombotic therapy either with systemic heparinization or with antiplatelet agents has been associated with improved neurologic outcomes. Care must be taken however given the high rate of numerous co-existing injuries as noted in the study where therapeutic anticoagulation may be contraindicated and have been reported to lead to longer hospital stays and increased morbidity/mortality.
The results of this study should raise the awareness for those that manage patients injured in MVC that although BCI is rare, early detection and anti-thrombotic therapy is appropriate to obtain optimal outcomes and reduce the likelihood of unnecessary morbidity and mortality. Multi-system trauma, especially long bone fracture, thoracic spine injury, cranio-fascial and pelvic fracture in MVC should raise the suspicion of BCI. Noteworthy, the authors made a point to comment in the introduction about the disparity between the incidence rates of ischemic stroke in the general population (20%) vs. those with BCI reported in this study (2%), but did not further address this in the discussion section, which is unfortunate.