A Systematic Review of the Benefits and Risks of Anticoagulation Following Traumatic Brain Injury

Thromboelastometry-Based Prophylaxis for Venous Thromboembolism in the Acute Period Following Isolated Severe Traumatic Brain Injury

Objective

Traumatic brain injury (TBI) is an independent risk factor for venous thromboembolism (VTE). This study aimed to determine the optimal timing for initiating pharmacological thromboprophylaxis for VTE in patients with isolated severe TBI using rotational thromboelastometry (ROTEM).

Methods

This single-center observational study enrolled 115 patients aged 18-59 years with isolated severe TBI within the first 48 hours after injury.

Results

Using ROTEM data, we identified hypercoagulation due to an increase in clot density (MCF EXTEM >72), which was attributed to fibrinogen (MCF FIBTEM >25). From day 4, hypercoagulation occurred in 14.8% of the patients. By day 7, these changes were observed in 85.2% of patients. According to brain computed tomography findings, patients who received early VTE chemoprophylaxis on days 3-4 after severe TBI did not experience progression of hemorrhagic foci.

Conclusion

Our results emphasize the clinical significance of thromboelastometry in patients with isolated severe traumatic TBI. Anticoagulant prophylaxis started on 3-4 days after severe TBI was relatively safe, and most patients did not experience hemorrhagic foci progression. The data acquired in this study may enable the optimization of VTE chemoprophylactic approaches, thereby reducing the associated risks to patients.

Impact of Antithrombotic Medications and Reversal Strategies on the Surgical Management and Outcomes of Traumatic Acute Subdural Hematoma

OBJECTIVE

Careful hematologic management is required in surgical patients with traumatic acute subdural hematoma (aSDH) taking antithrombotic medications. We sought to compare outcomes between patients with aSDH taking antithrombotic medications at admission who received antithrombotic reversal with patients with aSDH not taking antithrombotics.

METHODS

Retrospective review identified patients with traumatic aSDH requiring surgical evacuation. The cohort was divided based on antithrombotic use and whether pharmacologic reversal agents or platelet transfusions were administered. A 3-way comparison of outcomes was performed between patients taking anticoagulants who received pharmacologic reversal, patients taking antiplatelets who received platelet transfusion, and patients not taking antithrombotics. Multivariable regressions, adjusted for injury severity, further investigated associations with outcomes.

RESULTS

Of 138 patients who met inclusion criteria, 13.0% (n = 18) reported taking anticoagulants, 16.7% (n = 23) reported taking antiplatelets, and 3.6% (n = 5) reported taking both. Patients taking antiplatelets who received platelet transfusion had longer intraoperative times (P = 0.040) and higher rates of palliative care consultations (P = 0.046) compared with patients taking anticoagulants who received pharmacologic reversal and patients not taking antithrombotics. Across groups, no significant differences were found in frequency of in-hospital intracranial hemorrhage and venous thromboembolism, length of hospital stay, rate of inpatient mortality, or follow-up health status. In multivariable analysis, intraoperative time remained longest for the antiplatelets with platelet transfusion group. Other outcomes were not associated with patient group.

CONCLUSIONS

Among surgical patients with traumatic aSDH, those taking antiplatelet medications who receive platelet transfusions experience longer intraoperative procedure times and higher rates of palliative care consultation. Comparable outcomes were observed between patients receiving antithrombotic reversal and patients not taking antithrombotics.

Timing of Restarting Anticoagulation and Antiplatelet Therapies After Traumatic Subdural Hematoma-A Single Institution Experience

BACKGROUND

There is a paucity of information regarding the optimal timing of restarting antiplatelet therapy (APT) and anticoagulation therapy (ACT) after traumatic subdural hematoma (tSDH). Therefore, we sought to report our experience at a single level 1 trauma center with regard to restarting APT and/or ACT after tSDH.

METHODS

A total of 456 consecutive records were reviewed for unplanned hematoma evacuation within 90 days of discharge and thrombotic/thromboembolic events before restarting APT and/or ACT.

RESULTS

There was no difference in unplanned hematoma evacuation rate in patients not receiving APT or ACT (control) compared with those necessitating APT and/or ACT (6.4% control, 6.9% APT alone, 5.8% ACT alone, 5.4% APT and ACT). There was an increase in post-tSDH thrombosis/thromboembolism in patients needing to restart ACT (1.9% APT alone, P = 0.53 vs. control; 5.8% ACT alone, P = 0.04 vs. control; 16% APT and ACT; P < 0.001 vs. control). Subgroup analysis revealed that patients with coronary artery disease necessitating APT and patients with atrial fibrillation necessitating ACT had higher thrombosis/thromboembolism rates compared with controls (1.0% control vs. 6.1% coronary artery disease, P = 0.02; 1.0% control vs. 10.1% atrial fibrillation, P < 0.001). The median restart time of ACT was approximately 1 month after trauma; APT was restarted 2-4 weeks after trauma depending on clinical indication.

CONCLUSIONS

Patients requiring reinitiation of APT and/or ACT after tSDH were at elevated risk of thrombotic/thromboembolic events but not unplanned hematoma evacuation. Therefore, patients should be followed closely until APT and/or ACT are restarted, and consideration for earlier reinitiation of blood thinners should be given on a case-by-case basis.

Drug Use in Pediatric Patients Admitted to Rehabilitation For Severe Acquired Brain Injury: Analysis of the Associations With Rehabilitation Outcomes

INTRODUCTION

Patients with severe acquired brain injuries require drug therapies in intensive care for life support and injury treatment. Patients who then access rehabilitation usually maintain their drug treatments long term, with a potential influence on the rehabilitation course. Whereas drug effects have been reported for specific drugs and clinical issues in adults, comprehensive data on pediatric patients with traumatic and non-traumatic injuries are scant.

OBJECTIVES

The aims of this study were to describe the therapeutic classes and groups of drugs prescribed to pediatric inpatients recovering from severe acquired brain injury when they enter rehabilitation; to assess whether clinical variables may determine the use of drug classes; and to assess whether the use of drug classes may be associated with differences in rehabilitation outcomes.

METHODS

We carried out a retrospective chart review, following a previous study on the clinical-epidemiological characteristics of our patients. We collected information on drug therapies present at admittance to rehabilitation and analyzed their distribution according to therapeutic classes and groups. We verified the associations of drug groups with clinical variables (putatively antecedents to drug use) and with rehabilitation outcomes (putatively resultant of drug use and of clinical variables) in regression models. The clinical variables considered were injury etiology, Glasgow Outcome Score (GOS) at admittance to rehabilitation, sex, age at injury, plus two aggregate factors resulting from the previous work, 'neurological dysfunction' regarding the use of devices and 'injury severity' regarding the neurological status. The rehabilitation outcomes used were death after rehabilitation, persistence of a vegetative/minimally conscious state, coma duration, duration of the rehabilitation stay, rehabilitation efficiency (GOS at discharge minus GOS at admittance, divided by the length of rehabilitation stay).

RESULTS

We described the distribution of drug classes and groups among pediatric patients with severe acquired brain injuries. Regarding the associations between drug classes and clinical variables, we found greater use of cardiovascular agents with higher patient age, 'neurological dysfunction' score, and with an etiology of hypoxic brain injury. The use of antithrombotic agents was greater with higher patient age and 'neurological dysfunction' score. Glucocorticoid use was greater with higher GOS at admittance and with several etiologies: brain tumor, infective encephalitis, and autoimmune encephalitis. Regarding drug classes and rehabilitation outcomes, we found that the use of cardiovascular drugs was associated with increased occurrence of death after rehabilitation. The use of antispastic drugs was associated with a more frequent permanence in vegetative/minimally conscious states. The use of antispastic drugs and melatonin was associated with longer coma duration. The use of glucocorticoid drugs was associated with decreased rehabilitation efficiency.

CONCLUSIONS

We provided a description of drug use in pediatric rehabilitation after severe acquired brain injuries, which was lacking in the literature. Prospective studies should verify our associative observations regarding clinical variables, drugs use, and outcomes, to assess causality.

Therapeutic anticoagulation in patients with traumatic brain injuries and pulmonary emboli

BACKGROUND

Patients with traumatic intracranial hemorrhage (ICH) and concomitant pulmonary embolus (PE) have competing care needs and demand a careful balance of anticoagulation (AC) versus potential worsening of their ICH. The goal of this study is to determine the safety of therapeutic AC for PE in patients with ICH.

METHODS

This is a retrospective single-center study of patients older than 16 years with concomitant ICH and PE occurring between June 2013 and December 2017. Early AC was defined as within 7 days of injury or less; late was defined as after 7 days. Primary outcomes included death, interventions for worsening ICH following AC, and pulmonary complications. Multivariate logistic regression was used to evaluate for clinical and demographic factors associated with worsening traumatic brain injury (TBI), and recursive partitioning was used to differentiate risk in groups.

RESULTS

Fifty patients met criteria. Four did not receive any AC and were excluded. Nineteen (41.3%) received AC early (median, 4.1; interquartile range, 3.1-6) and 27 (58.7%) received AC late (median, 14; interquartile range, 9.7-19.5). There were four deaths in the early group, and none in the late cohort (21.1% vs. 0%, p = 0.01). Two deaths were due to PE and the others were from multi-system organ failure or unrecoverable underlying TBI. Three patients in the early group, and two in the late, had increased ICH on computed tomography (17.6% vs. 7.4%, p = 0.3). None required intervention.

CONCLUSION

This retrospective study failed to find instances of clinically significant progression of TBI in 46 patients with computed tomography-proven ICH after undergoing AC for PE. Therapeutic AC is not associated with worse outcomes in patients with TBI, even if initiated early. However, two patients died from PE despite AC, underlining the severity of the disease. Intracranial hemorrhage should not preclude AC treatment for PE, even early after injury.

LEVEL OF EVIDENCE

Care management, Level IV.

Rehabilitation from meningioma

This chapter discusses the complex process of acute rehabilitation of patients after meningioma. Acute inpatient rehabilitation after meningioma utilizes an interdisciplinary approach to provide comprehensive rehabilitation through a team of physical, occupational, and speech therapists, nurses, doctors, recreational therapists, neuropsychologists, case managers and social workers, all of whom specialize in providing rehabilitation care. The prognosis of rehabilitation outcomes in this population is similar to that of the stroke population, and patients benefit from rehabilitation to maximize function in the setting of ongoing treatment. Common functional deficits include speech, cognitive, motor, and visual deficits. Medical complications include heterotopic ossification, venous thromboembolism, bowel and bladder complications, and pain. Patients must also be managed for behavioral complications such as agitation and maintenance of the sleep-wake cycle. The wide variety of functional outcomes following meningioma diagnosis and treatment necessitates a flexible rehabilitation course including testing for deficits, monitoring of outcomes, and ongoing therapy support.

Bloodletting Puncture at Hand Twelve Jing-Well Points Improves Neurological Recovery by Ameliorating Acute Traumatic Brain Injury-Induced Coagulopathy in Mice

Traumatic brain injury (TBI) contributes to hypocoagulopathy associated with prolonged bleeding and hemorrhagic progression. Bloodletting puncture therapy at hand twelve Jing-well points (BL-HTWP) has been applied as a first aid measure in various emergent neurological diseases, but the detailed mechanisms of the modulation between the central nervous system and systemic circulation after acute TBI in rodents remain unclear. To investigate whether BL-HTWP stimulation modulates hypocoagulable state and exerts neuroprotective effect, experimental TBI model of mice was produced by the controlled cortical impactor (CCI), and treatment with BL-HTWP was immediately made after CCI. Then, the effects of BL-HTWP on the neurological function, cerebral perfusion state, coagulable state, and cerebrovascular histopathology post-acute TBI were determined, respectively. Results showed that BL-HTWP treatment attenuated cerebral hypoperfusion and improve neurological recovery post-acute TBI. Furthermore, BL-HTWP stimulation reversed acute TBI-induced hypocoagulable state, reduced vasogenic edema and cytotoxic edema by regulating multiple hallmarks of coagulopathy in TBI. Therefore, we conclude for the first time that hypocoagulopathic state occurs after acute experimental TBI, and the neuroprotective effect of BL-HTWP relies on, at least in part, the modulation of hypocoagulable state. BL-HTWP therapy may be a promising strategy for acute severe TBI in the future.

The European guideline on management of major bleeding and coagulopathy following trauma: fifth edition

BACKGROUND

Severe traumatic injury continues to present challenges to healthcare systems around the world, and post-traumatic bleeding remains a leading cause of potentially preventable death among injured patients. Now in its fifth edition, this document aims to provide guidance on the management of major bleeding and coagulopathy following traumatic injury and encourages adaptation of the guiding principles described here to individual institutional circumstances and resources.

METHODS

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma was founded in 2004, and the current author group included representatives of six relevant European professional societies. The group applied a structured, evidence-based consensus approach to address scientific queries that served as the basis for each recommendation and supporting rationale. Expert opinion and current clinical practice were also considered, particularly in areas in which randomised clinical trials have not or cannot be performed. Existing recommendations were re-examined and revised based on scientific evidence that has emerged since the previous edition and observed shifts in clinical practice. New recommendations were formulated to reflect current clinical concerns and areas in which new research data have been generated.

RESULTS

Advances in our understanding of the pathophysiology of post-traumatic coagulopathy have supported improved management strategies, including evidence that early, individualised goal-directed treatment improves the outcome of severely injured patients. The overall organisation of the current guideline has been designed to reflect the clinical decision-making process along the patient pathway in an approximate temporal sequence. Recommendations are grouped behind the rationale for key decision points, which are patient- or problem-oriented rather than related to specific treatment modalities. While these recommendations provide guidance for the diagnosis and treatment of major bleeding and coagulopathy, emerging evidence supports the author group's belief that the greatest outcome improvement can be achieved through education and the establishment of and adherence to local clinical management algorithms.

CONCLUSIONS

A multidisciplinary approach and adherence to evidence-based guidance are key to improving patient outcomes. If incorporated into local practice, these clinical practice guidelines have the potential to ensure a uniform standard of care across Europe and beyond and better outcomes for the severely bleeding trauma patient.

Coagulopathy and haemorrhagic progression in traumatic brain injury: advances in mechanisms, diagnosis, and management

Normal haemostasis depends on an intricate balance between mechanisms of bleeding and mechanisms of thrombosis, and this balance can be altered after traumatic brain injury (TBI). Impaired haemostasis could exacerbate the primary insult with risk of initiation or aggravation of bleeding; anticoagulant use at the time of injury can also contribute to bleeding risk after TBI. Many patients with TBI have abnormalities on conventional coagulation tests at admission to the emergency department, and the presence of coagulopathy is associated with increased morbidity and mortality. Further blood testing often reveals a range of changes affecting platelet numbers and function, procoagulant or anticoagulant factors, fibrinolysis, and interactions between the coagulation system and the vascular endothelium, brain tissue, inflammatory mechanisms, and blood flow dynamics. However, the degree to which these coagulation abnormalities affect TBI outcomes and whether they are modifiable risk factors are not known. Although the main challenge for management is to address the risk of hypocoagulopathy with prolonged bleeding and progression of haemorrhagic lesions, the risk of hypercoagulopathy with an increased prothrombotic tendency also warrants consideration.

Response of the cerebral vasculature following traumatic brain injury

The critical role of the vasculature and its repair in neurological disease states is beginning to emerge particularly for stroke, dementia, epilepsy, Parkinson's disease, tumors and others. However, little attention has been focused on how the cerebral vasculature responds following traumatic brain injury (TBI). TBI often results in significant injury to the vasculature in the brain with subsequent cerebral hypoperfusion, ischemia, hypoxia, hemorrhage, blood-brain barrier disruption and edema. The sequalae that follow TBI result in neurological dysfunction across a host of physiological and psychological domains. Given the importance of restoring vascular function after injury, emerging research has focused on understanding the vascular response after TBI and the key cellular and molecular components of vascular repair. A more complete understanding of vascular repair mechanisms are needed and could lead to development of new vasculogenic therapies, not only for TBI but potentially vascular-related brain injuries. In this review, we delineate the vascular effects of TBI, its temporal response to injury and putative biomarkers for arterial and venous repair in TBI. We highlight several molecular pathways that may play a significant role in vascular repair after brain injury.

Early venous thromboembolism chemoprophylaxis in combat-related penetrating brain injury

OBJECTIVE Traumatic brain injury (TBI) is independently associated with deep vein thrombosis (DVT) and pulmonary embolism (PE). Given the numerous studies of civilian closed-head injury, the Brain Trauma Foundation recommends venous thromboembolism chemoprophylaxis (VTC) after severe TBI. No studies have specifically examined this practice in penetrating brain injury (PBI). Therefore, the authors examined the safety and effectiveness of early VTC after PBI with respect to worsening intracranial hemorrhage and DVT or PE. METHODS The Kandahar Airfield neurosurgery service managed 908 consults between January 2010 and March 2013. Eighty of these were US active duty members with PBI, 13 of whom were excluded from analysis because they presented with frankly nonsurvivable CNS injury or they died during initial resuscitation. This is a retrospective analysis of the remaining 67 patients. RESULTS Thirty-two patients received early VTC and 35 did not. Mean time to the first dose was 24 hours. Fifty-two patients had blast-related PBI and 15 had gunshot wounds (GSWs) to the head. The incidence of worsened intracranial hemorrhage was 16% after early VTC and 17% when it was not given, with the relative risk approaching 1 (RR = 0.91). The incidence of DVT or PE was 12% after early VTC and 17% when it was not given (RR = 0.73), though this difference was not statistically significant. CONCLUSIONS Early VTC was safe with regard to the progression of intracranial hemorrhage in this cohort of combat-related PBI patients. Data in this study suggest that this intervention may have been effective for the prevention of DVT or PE but not statistically significantly so. More research is needed to clarify the safety and efficacy of this practice.

Targeting coagulation factor XII as a novel therapeutic option in brain trauma

OBJECTIVE

Traumatic brain injury is a major global public health problem for which specific therapeutic interventions are lacking. There is, therefore, a pressing need to identify innovative pathomechanism-based effective therapies for this condition. Thrombus formation in the cerebral microcirculation has been proposed to contribute to secondary brain damage by causing pericontusional ischemia, but previous studies have failed to harness this finding for therapeutic use. The aim of this study was to obtain preclinical evidence supporting the hypothesis that targeting factor XII prevents thrombus formation and has a beneficial effect on outcome after traumatic brain injury.

METHODS

We investigated the impact of genetic deficiency of factor XII and acute inhibition of activated factor XII with a single bolus injection of recombinant human albumin-fused infestin-4 (rHA-Infestin-4) on trauma-induced microvascular thrombus formation and the subsequent outcome in 2 mouse models of traumatic brain injury.

RESULTS

Our study showed that both genetic deficiency of factor XII and an inhibition of activated factor XII in mice minimize trauma-induced microvascular thrombus formation and improve outcome, as reflected by better motor function, reduced brain lesion volume, and diminished neurodegeneration. Administration of human factor XII in factor XII-deficient mice fully restored injury-induced microvascular thrombus formation and brain damage.

INTERPRETATION

The robust protective effect of rHA-Infestin-4 points to a novel treatment option that can decrease ischemic injury after traumatic brain injury without increasing bleeding tendencies. Ann Neurol 2016;79:970-982.

The European guideline on management of major bleeding and coagulopathy following trauma: fourth edition

BACKGROUND

Severe trauma continues to represent a global public health issue and mortality and morbidity in trauma patients remains substantial. A number of initiatives have aimed to provide guidance on the management of trauma patients. This document focuses on the management of major bleeding and coagulopathy following trauma and encourages adaptation of the guiding principles to each local situation and implementation within each institution.

METHODS

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma was founded in 2004 and included representatives of six relevant European professional societies. The group used a structured, evidence-based consensus approach to address scientific queries that served as the basis for each recommendation and supporting rationale. Expert opinion and current clinical practice were also considered, particularly in areas in which randomised clinical trials have not or cannot be performed. Existing recommendations were reconsidered and revised based on new scientific evidence and observed shifts in clinical practice; new recommendations were formulated to reflect current clinical concerns and areas in which new research data have been generated. This guideline represents the fourth edition of a document first published in 2007 and updated in 2010 and 2013.

RESULTS

The guideline now recommends that patients be transferred directly to an appropriate trauma treatment centre and encourages use of a restricted volume replacement strategy during initial resuscitation. Best-practice use of blood products during further resuscitation continues to evolve and should be guided by a goal-directed strategy. The identification and management of patients pre-treated with anticoagulant agents continues to pose a real challenge, despite accumulating experience and awareness. The present guideline should be viewed as an educational aid to improve and standardise the care of the bleeding trauma patients across Europe and beyond. This document may also serve as a basis for local implementation. Furthermore, local quality and safety management systems need to be established to specifically assess key measures of bleeding control and outcome.

CONCLUSIONS

A multidisciplinary approach and adherence to evidence-based guidance are key to improving patient outcomes. The implementation of locally adapted treatment algorithms should strive to achieve measureable improvements in patient outcome.

The Formation of Microthrombi in Parenchymal Microvessels after Traumatic Brain Injury Is Independent of Coagulation Factor XI

Microthrombus formation and bleeding worsen the outcome after traumatic brain injury (TBI). The aim of the current study was to characterize these processes in the brain parenchyma after experimental TBI and to determine the involvement of coagulation factor XI (FXI). C57BL/6 mice (n = 101) and FXI-deficient mice (n = 15) were subjected to controlled cortical impact (CCI). Wild-type mice received an inhibitory antibody against FXI (14E11) or control immunoglobulin G 24 h before or 30 or 120 min after CCI. Cerebral microcirculation was visualized in vivo by 2-photon microscopy 2-3 h post-trauma and histopathological outcome was assessed after 24 h. TBI induced hemorrhage and microthrombus formation in the brain parenchyma (p < 0.001). Inhibition of FXI activation or FXI deficiency did not reduce cerebral thrombogenesis, lesion volume, or hemispheric swelling. However, it also did not increase intracranial hemorrhage. Formation of microthrombosis in the brain parenchyma after TBI is independent of the intrinsic coagulation cascade since it was not reduced by inhibition of FXI. However, since targeting FXI has well-established antithrombotic effects in humans and experimental animals, inhibition of FXI could represent a reasonable strategy for the prevention of deep venous thrombosis in immobilized patients with TBI.