Management of Extracranial Blunt Cerebrovascular Injuries: Experience with an Aspirin-Based Approach

Antiplatelets versus anticoagulants in the treatment of blunt cerebrovascular injury (BCVI) - A systematic review and meta-analysis

INTRODUCTION

Blunt cerebrovascular injury (BCVI) occurs in 1-3% of blunt traumas and is associated with stroke, disability, and mortality if unrecognized and untreated. Early detection and treatment are imperative to reduce the risk of stroke, however, there is significant variation amongst centers and trauma care providers in the specific medical management strategy used. This study compares antiplatelets vs. anticoagulants to determine BCVI-related stroke risk and bleeding complications to better understand the efficacy and safety of various treatment strategies.

METHODS

A systematic review of MEDLINE, Embase, and Cochrane CENTRAL databases was conducted with the assistance of a medical librarian. The search was supplemented with manual review of the literature. Included studies reported treatment-stratified risk of stroke following BCVI. All studies were screened independently by two reviewers, and data was extracted in duplicate. Meta-analysis was conducted using pooled estimates of odds ratios (OR) with a random-effects model using Mantel-Haenszel methods.

RESULTS

A total of 3315 studies screened yielded 39 studies for inclusion, evaluating 6552 patients (range 8 - 920 per study) with a total of 7643 BCVI. Stroke rates ranged from 0% to 32.8%. Amongst studies included in the meta-analysis, there were a total of 405 strokes, with 144 (35.5%) occurring on therapy, for a total stroke rate of 4.5 %. Meta-analysis showed that stroke rate after BCVI was lower for patients treated with antiplatelets vs. anticoagulants (OR 0.57; 95% CI 0.33-0.96, p = 0.04); when evaluating only the 9 studies specifically comparing ASA to heparin, the stroke rate was similar between groups (OR 0.43; 95% CI 0.15-1.20, p = 0.11). Eleven studies evaluated bleeding complications and demonstrated lower risk of bleeding with antiplatelets vs. anticoagulants (OR 0.29; 95% CI 0.13-0.63, p = 0.002); 5 studies evaluating risk of bleeding complications with ASA vs. heparin showed lower rates of bleeding complications with ASA (OR 0.16; 95% CI 0.04-0.58, p = 0.005).

CONCLUSIONS

Treatment of patients with BCVI with antiplatelets is associated with lower risks of stroke and bleeding complications compared to treatment with anticoagulants. Use of ASA vs. heparin specifically was not associated with differences in stroke risk, however, patients treated with ASA had fewer bleeding complications. Based on this evidence, antiplatelets should be the preferred treatment strategy for patients with BCVI.

Stroke Prevention in Blunt Cerebrovascular Injury: Role of Aspirin 81 mg

BACKGROUND

The stroke rate in blunt cerebrovascular injury (BCVI) varies from 25% without treatment to less than 8% with antithrombotic therapy. There is no consensus on the optimal management to prevent stroke BCVI. We investigated the efficacy and safety of oral Aspirin (ASA) 81 mg to prevent BCVI-related stroke compared to historically reported stroke rates with ASA 325 mg and heparin.

METHODS

A single-center retrospective study included adult trauma patients who received oral ASA 81 mg for BCVI management between 2013 and 2022. Medical records were reviewed for demographic and injury characteristics, imaging findings, treatment-related complications, and outcomes.

RESULTS

Eighty-four patients treated with ASA 81 mg for BCVI were identified. The mean age was 41.50 years, and 61.9% were male. The mean Injury Severity Score and Glasgow Coma Scale were 19.82 and 12.12, respectively. A total of 101 vessel injuries were identified, including vertebral artery injuries in 56.4% and carotid artery injuries in 44.6%. Traumatic brain injury was found in 42.9%, and 16.7% of patients had a solid organ injur. Biffl grade I (52.4%) injury was the most common, followed by grade II (37.6%) and grade III (4.9%). ASA 81 mg was started in the first 24 hours in 67.9% of patients, including 20 patients with traumatic brain injury and 8 with solid organ injuries. BCVI-related stroke occurred in 3 (3.5%) patients with Biffl grade II (n = 2) and III (n = 1). ASA-related complications were not identified in any patient. The mean length of stay in the hospital was 10.94 days, and 8 patients died during hospitalization due to complications of polytrauma. Follow-up with computed tomography angiography was performed in 8 (9.5%) patients, which showed improvement in 5 and a stable lesion in 3 at a mean time of 58 days after discharge.

CONCLUSIONS

In the absence of clear guidelines regarding appropriate medication, BCVI management should be individualized case-by-case through a multidisciplinary approach. ASA 81 mg is a viable option for BCVI-related stroke prevention compared to the reported stroke rates (2%-8%) with commonly used antithrombotics like heparin and ASA 325 mg. Future prospective studies are needed to provide insight into the safety and efficacy of the current commonly used agent in managing BCVI.

Analysis of Extracranial Cerebrovascular Injuries: Clinical Predictors of Management and Outcomes

BACKGROUND

Optimal management of traumatic extracranial cerebrovascular injuries (ECVIs) remains undefined. We sought to evaluate the factors that influence management and neurologic outcomes (stroke and brain death) following traumatic ECVI.

METHODS

A retrospective review of a single level 1 trauma center's prospectively maintained data registry of patients older than 18 years of age with a diagnosis of ECVI was performed from 2013 to 2019. Injuries limited to the external carotid artery were excluded. Patient demographics, type of injury, timing of presentation, Biffl Classification of Cerebrovascular Injury Grade, Injury Severity Score (ISS), and Abbreviated Injury Scale were documented. Ultimate treatments (medical management and procedural interventions) and brain-related outcomes (stroke and brain death) were recorded.

RESULTS

ECVIs were identified in 96 patients. The primary mechanism of injury was blunt trauma (89.5% vs. 10.5%, blunt versus penetrating), with 70 cases (66%) of vertebral artery injury and 37 cases of carotid artery injury. Treatments included vascular intervention (6.5%) and medical management (93.5%). Overall outcomes included ipsilateral ischemic stroke (29%) and brain death (6.5%). In the carotid group, vascular intervention was associated with higher Biffl grades (mean Biffl 3.17 vs. 2.23; P = 0.087) and decreased incidence of brain death (0% vs. 19%, P = 0.006), with no difference seen in ISS scores. Brain death was associated with higher ISS scores (40.29 vs. 24.17, P = 0.01), lower glascow coma score on arrival (3.57 vs. 10.63, P < 0.001), and increased rates of ischemic stroke (71% vs. 30%, P = 0.025). In the vertebral group, neither Biffl grade nor ISS were associated with treatment or outcomes. Regarding the timing of stroke in ECVI, there was no significant difference in the time from presentation to cerebral infarction between the carotid and vertebral artery groups (24.7 hr vs. 21.20 hr, P = 0.739). After this window, 98% of the ECVI cases demonstrated no further aneurysmal degeneration or new neurological deficits beyond the early time period (mean follow-up 9.7 months).

CONCLUSIONS

Blunt cerebrovascular injuries should be viewed distinctly in the carotid and vertebral territories. In cases of injury to the carotid artery, Biffl grade and ISS score are associated with surgical intervention and neurologic events, respectively; vertebral artery injuries did not share this association. Neurologic deficits were detected in a similar time frame between the carotid artery and the vertebral artery injury groups and both groups had rare late neurologic events.

Efficacy of Antithrombotic Therapy and Risk of Hemorrhagic Complication in Blunt Cerebrovascular Injury Patients with Concomitant Injury: A Systematic Review

BACKGROUND

The risk-benefit balance of antithrombotic therapy administration for blunt cerebrovascular injuries (BCVI) patients with concomitant injuries at high risk for bleeding is an ongoing therapeutic conundrum for trauma clinicians. We performed a systematic review to assess the reported efficacy and safety of treatment in this population with respect to prevention of ischemic stroke and risk of hemorrhagic complications.

STUDY DESIGN

A systematic electronic literature search of MEDLINE, EMBASE, Cochrane Library, and Web of Science databases was performed from January 1, 1996 to December 31, 2021. Studies were included if they reported treatment-stratified clinical outcomes after antithrombotic therapy in BCVI patients with concomitant injuries at high risk of bleeding into a critical site. Data were extracted from selected studies by two independent reviewers, including the main outcomes of interest were BCVI-related ischemic stroke rates and rates of hemorrhagic complications.

RESULTS

Of the 5,999 studies reviewed, 10 reported on the effects of treating BCVI patients with concurrent traumatic injuries and were included for review. In the pooled data, among patients with BCVI and concomitant injury who received any form of antithrombotic therapy, the BCVI-related stroke rate was 7.6%. The subgroup of patients who did not receive therapy had an overall BCVI-related stroke rate of 34%. The total rate of hemorrhagic complications in the treated population was 3.4%.

CONCLUSIONS

In BCVI patients with concomitant injuries at high risk for bleeding, antithrombotic use reduces the risk of ischemic strokes with a low reported risk of serious hemorrhagic complications.

Establishing a core outcome set for blunt cerebrovascular injury: an EAST modified Delphi method consensus study

Objectives

Our understanding of blunt cerebrovascular injury (BCVI) has changed significantly in recent decades, resulting in a heterogeneous description of diagnosis, treatment, and outcomes in the literature which is not suitable for data pooling. Therefore, we endeavored to develop a core outcome set (COS) to help guide future BCVI research and overcome the challenge of heterogeneous outcomes reporting.

Methods

After a review of landmark BCVI publications, content experts were invited to participate in a modified Delphi study. For round 1, participants submitted a list of proposed core outcomes. In subsequent rounds, panelists used a 9-point Likert scale to score the proposed outcomes for importance. Core outcomes consensus was defined as >70% of scores receiving 7 to 9 and <15% of scores receiving 1 to 3. Feedback and aggregate data were shared between rounds, and four rounds of deliberation were performed to re-evaluate the variables not achieving predefined consensus criteria.

Results

From an initial panel of 15 experts, 12 (80%) completed all rounds. A total of 22 items were considered, with 9 items achieving consensus for inclusion as core outcomes: incidence of postadmission symptom onset, overall stroke incidence, stroke incidence stratified by type and by treatment category, stroke incidence prior to treatment initiation, time to stroke, overall mortality, bleeding complications, and injury progression on radiographic follow-up. The panel further identified four non-outcome items of high importance for reporting: time to BCVI diagnosis, use of standardized screening tool, duration of treatment, and type of therapy used.

Conclusion

Through a well-accepted iterative survey consensus process, content experts have defined a COS to guide future research on BCVI. This COS will be a valuable tool for researchers seeking to perform new BCVI research and will allow future projects to generate data suitable for pooled statistical analysis with enhanced statistical power.

Level of evidence

Level IV.

Imaging analysis of ischemic strokes due to blunt cerebrovascular injury

BACKGROUND

The timing of stroke onset among patients with blunt cerebrovascular injury (BCVI) is not well understood. All blunt trauma patients at our institution undergo a screening computed tomographic angiography (CTA) of the neck. Most patients with CTA evidence of BCVI are treated with aspirin, and all patients with clinical evidence of stroke are treated with aspirin and undergo magnetic resonance imaging (MRI) of the brain. We conducted a retrospective review to determine the incidence of stroke upon admission and following admission.

METHODS

All neck CTAs and head MRIs obtained in blunt trauma patients were reviewed from August 2017 to August 2019. All CTAs that were interpreted as showing BCVI were individually reviewed to confirm the diagnosis of BCVI. Stroke was defined as brain MRI evidence of new ischemic lesions, and each MRI was reviewed to identify the brain territory affected. We extracted the time to aspirin administration and the timing of stroke onset from patients' electronic health records.

RESULTS

Of the 6,849 blunt trauma patients, 479 (7.0%) had BCVIs. Twenty-four patients (5.0%) with BCVI had a stroke on admission. Twelve (2.6%) of the remaining 455 patients subsequently had a stroke during their hospitalization. The incidence of stroke among patients with BCVI was 7.5%; 2.6% were potentially preventable. Only 5 of the 12 patients received aspirin before the onset of stroke symptoms. All 36 patients with BCVI and stroke had thromboembolic lesions in the territory supplied by an injured vessel.

CONCLUSION

With universal screening, CTA evidence of BCVI is common among blunt trauma patients. Although acute stroke is also relatively common in this population, two thirds of strokes are already evident on admission. One third of BCVI-related strokes occur after admission and often relatively early, necessitating rapid commencement of preventative treatment. Further studies are required to demonstrate the value of antithrombotic administration in preventing stroke in BCVI patients.

LEVEL OF EVIDENCE

Prognostic and Epidemiologic; Level IV.

Antithrombotic choice in blunt cerebrovascular injuries: Experience at a tertiary trauma center, systematic review, and meta-analysis

BACKGROUND

Blunt cerebrovascular injuries (BCVIs) may occur following trauma and lead to ischemic stroke if untreated. Antithrombotic therapy decreases this risk; however, the optimal agent has yet to be determined in this population. The aim of this study was to compare the risk-benefit profile of antiplatelet (AP) versus anticoagulant (AC) therapy in rates of ischemic stroke and hemorrhagic complications in BCVI patients.

METHODS

We performed a retrospective review of BCVI patients at our tertiary care Trauma hospital from 2010 to 2015, and a systematic review and meta-analysis of the literature. The OVID Medline, Embase, Web of Science, and Cochrane Library databases were searched from inception to September 16, 2019. References of included publications were searched manually for other relevant articles. The search was limited to articles in humans, in patients 18 years or older, and in English. Studies that reported treatment-stratified clinical outcomes following AP or AC treatment in BCVI patients were included. Exclusion criteria included case reports, case series with n < 5, review articles, conference abstracts, animal studies, and non-peer-reviewed publications. Data were extracted from each study independently by two reviewers, including study design, country of origin, sex and age of patients, Injury Severity Score, Biffl grade, type of treatment, ischemic stroke rate, and hemorrhage rate. Pooled estimates using odds ratio (OR) were combined using a random-effects model using a Mantel-Hanzel weighting. The main outcome of interest was rate of ischemic stroke due to BCVI, and the secondary outcome was hemorrhage rate based on AC or AP treatment.

RESULTS

In total, there were 2044 BCVI patients, as reported in the 22 studies in combination with our institutional data. The stroke rate was not significantly different between the two treatment groups (OR, 1.27; 95% confidence interval, 0.40-3.99); however, the hemorrhage rate was decreased in AP versus AC treated groups (OR, 0.38; 95% confidence interval, 0.15-1.00).

CONCLUSION

Based on this meta-analysis, both AC and AP seem similarly effective in preventing ischemic stroke, but AP is better tolerated in the trauma population. This suggests that AP therapy may be preferred, but this should be further assessed with prospective randomized trials.

LEVEL OF EVIDENCE

Review article, level II.

Treatment of asymptomatic blunt cerebrovascular injury (BCVI): a systematic review

Background

The management of asymptomatic blunt cerebrovascular injury (BCVI) with respect to stroke prevention and vessel healing is challenging.

Objectives

The aim of this systematic review was to determine if a specific treatment results in lower stroke rates and/or improved vessel healing in asymptomatic BCVI.

Data sources

An electronic literature search of MEDLINE, EMBASE, Cochrane Library, CINAHL, SCOPUS, Web of Science, and ClinicalTrials.gov performed from inception to March 2020.

Study eligibility criteria

Studies were included if they reported on a comparison of any treatment for BCVI and stroke and/or vessel healing rates.

Participants and interventions

Adult patients diagnosed with asymptomatic BCVI(s) who were treated with any preventive medication or procedure.

Study appraisal and synthesis methods

All studies were systematically reviewed and bias was evaluated by the Newcastle-Ottawa Scale. No meta-analysis was performed secondary to significant heterogeneity across studies in patient population, screening protocols, and treatment selection. The main outcomes were stroke and healing rate.

Results

Of 8781 studies reviewed, 19 reported on treatment effects for asymptomatic BCVI and were included for review. Any choice of medical management was better than no treatment, but no specific differences between choice of medical management and stroke outcomes were found. Vessel healing was rare and the majority of healed vessels were following low-grade injuries.

Limitations

Majority of the included studies were retrospective and at high risk of bias.

Conclusions or implications of key findings

Asymptomatic BCVI should be treated medically using a consistent, local protocol. High-quality studies on the effect of individual antithrombotic agents on stroke rates and vessel healing for asymptomatic BCVI are required.

Aspirin versus anticoagulation for stroke prophylaxis in blunt cerebrovascular injury: a propensity-matched retrospective cohort study

OBJECTIVE

The goal of this study was to compare the odds of stroke 24 hours or more after hospital arrival among patients with blunt cerebrovascular injury (BCVI) who were treated with therapeutic anticoagulation versus aspirin.

METHODS

The authors conducted a retrospective cohort study at a regional level I trauma center including all patients with BCVI who were treated over a span of 10 years. Individuals with stroke on arrival or within the first 24 hours were excluded, as were those receiving alternative antithrombotic drugs or procedural treatment. Exact logistic regression was used to examine the association between treatment and stroke, adjusting for injury grade. To account for the possibility of residual confounding, propensity scores for the likelihood of receiving anticoagulation were determined and used to match patients from each treatment group; the difference in the probability of stroke between the two groups was then calculated.

RESULTS

A total of 677 patients with BCVI receiving aspirin or anticoagulation were identified. A total of 3.8% (n = 23) of 600 patients treated with aspirin sustained a stroke, compared to 11.7% (n = 9) of 77 receiving anticoagulation. After adjusting for injury grade with exact regression, anticoagulation was associated with higher likelihood of stroke (OR 3.01, 95% CI 1.00-8.21). In the propensity-matched analysis, patients who received anticoagulation had a 15.0% (95% CI 3.7%-26.3%) higher probability of sustaining a stroke compared to those receiving aspirin.

CONCLUSIONS

Therapeutic anticoagulation may be inferior to aspirin for stroke prevention in BCVI. Prospective research is warranted to definitively compare these treatment strategies.

Risk Factors and Outcomes Associated with Blunt Cerebrovascular Injury in Patients with Mild or Moderate Traumatic Brain Injury

BACKGROUND

Blunt cerebrovascular injury (BCVI) represents a spectrum of traumatic injuries to the carotid and vertebral arteries that is an often-overlooked source of morbidity and mortality. Its incidence, risk factors, and effect on outcomes in patients with mild or moderate traumatic brain injury (mTBI) have not been studied independently.

METHODS

The National Trauma Data Bank from 2013 to 2017 was queried to identify patients with mTBI who suffered blunt injuries. BCVI was identified using abbreviated injury scores and included blunt carotid artery injury (BCAI) and blunt vertebral artery injury (BVAI). A binary logistic regression was used to identify patient-related and injury-related factors associated with BCVI. Binary logistic regressions were also performed to evaluate the effect of BCVI on stroke, in-hospital mortality, nonroutine discharge disposition, total length of stay (LOS), intensive care unit LOS, and number of days mechanically ventilated.

RESULTS

Of 485,880 patients with mTBI, there were 4,382 (0.9%) with BCVI. Cervical spine fracture was the strongest factor associated with BCAI (odds ratio [OR], 1.97; 95% confidence interval [95% CI], 1.77-2.19), followed by mandible fracture and basilar skull fracture. Cervical spine fracture also had the strongest association with BVAI (OR, 18.28; 95% CI, 16.47-20.28), followed by spinal cord injury and neck contusion. Stroke was more common in patients with BCAI (OR, 5.50; 95% CI, 4.19-7.21) and BVAI (OR, 7.238; 95% CI, 5.929-8.836). BVAI increased the odds of mortality, but BCAI did not. Both were associated with nonroutine discharge and increased LOS, intensive care unit LOS, and number of days mechanically ventilated.

CONCLUSIONS

The incidence of BCVI in patients with mTBI is low, and it usually does not require invasive treatment. However, it is associated with greater odds of stroke and negative outcomes. Knowledge of risk factors for BCVI may tailor further investigation to aid prompt diagnosis.

Pharmacologic Therapy is Not Associated with Stroke Prevention in Patients with Isolated Blunt Vertebral Artery Injury

BACKGROUND

Vertebral artery injury (VAI) is often grouped with carotid artery injury into a broader classification of blunt cerebrovascular injury, despite fundamental differences in mechanism of injury and outcome. This study seeks to evaluate the efficacy of medical therapy in preventing strokes for isolated VAI.

METHODS

Patients with isolated blunt VAI (2011-2018) were identified from the trauma registry of a level I trauma center. A retrospective chart review was conducted excluding patients with concomitant carotid artery injury. Factors examined included demographics, injury characteristics, anatomic classification, and management strategy. Patients were stratified by whether they received pharmacological (antiplatelet or anticoagulation) therapy. The primary outcome was new posterior circulation stroke within 30 days of injury as confirmed by imaging studies.

RESULTS

A total of 206 patients with blunt VAI were included. Median Injury Severity Score was 17 and 33 (16.0%) patients presented with Glasgow Coma Scale <8. The most common mechanism of injury was motor vehicle collision (58.7%). The injuries were bilateral in 38 (18.5%) patients and 73 (35.4%) suffered multisegmental injuries. The anatomic severity of injuries was Grade 1 = 38.8%, Grade 2 = 25.7%, Grade 3 = 4.9%, Grade 4 = 30.6%, and Grade 5 = 0.5%. There was no correlation between anatomic grade and stroke (P = 0.11) or initiation of pharmacologic therapy (P = 0.30). In total, 172 (84%) patients received pharmacological therapy with no differences in baseline characteristics between treated and untreated patients. Overall, the 30-day stroke rate was 1.9%. There was no difference in stroke rate between patients who received medical therapy versus those who did not (5.9% vs. 1.2%, P = 0.13). In subgroup analysis by injury severity, medical therapy did not improve stroke rates. Among patients treated with aspirin, there was no difference in stroke rate between doses of 81 vs. 325 mg (1.1% vs. 0%, P = 1).

CONCLUSIONS

Isolated VAI is associated with a very low risk of stroke and treatment with medical therapies including antiplatelet or anticoagulation does not improve risk of stroke.