Association Between Prehospital Tranexamic Acid Administration and Outcomes of Severe Traumatic Brain Injury

Tranexamic Acid Use in the Surgical Arena: A Narrative Review

INTRODUCTION

Tranexamic acid (TXA) is a potent antifibrinolytic drug that inhibits the activation of plasmin by plasminogen. While not a new medication, TXA has quickly gained traction across a variety of surgical subspecialties to prevent and treat bleeding. Knowledge on the use of this drug is essential for the modern surgeon to continue to provide excellent care to their patients.

METHODS

A comprehensive review of the PubMed database was conducted of articles published within the last 10 y (2014-2024) relating to TXA and its use in various surgical subspecialties. Seminal studies regarding the use of TXA older than 10 y were included from the author's archives.

RESULTS

Indications for TXA are not limited to trauma alone, and TXA is utilized across a variety of surgical subspecialties from neurosurgery to hepatic surgery to control hemorrhage. Overall, TXA is well tolerated with common dose-dependent adverse effects, including headache, nasal symptoms, dizziness, nausea, diarrhea, and fatigue. More severe adverse events are rare and easily mitigated by not exceeding a dose of 50 mg/kg.

CONCLUSIONS

The administration of TXA as an adjunct to treat trauma saves lives. The ability of TXA to induce seizures is dose dependent with identifiable risk factors, making this serious adverse effect predictable. As for the potential for TXA to cause thrombotic events, uncertainty remains. If this association is proven to be real, the risk will likely be small, since the use of TXA is still advantageous in most situations because of its efficacy for a more common concern, bleeding.

Strategies to prevent blood loss and reduce transfusion in emergency general surgery, WSES-AAST consensus paper

Emergency general surgeons often provide care to severely ill patients requiring surgical interventions and intensive support. One of the primary drivers of morbidity and mortality is perioperative bleeding. In general, when addressing life threatening haemorrhage, blood transfusion can become an essential part of overall resuscitation. However, under all circumstances, indications for blood transfusion must be accurately evaluated. When patients decline blood transfusions, regardless of the reason, surgeons should aim to provide optimal care and respect and accommodate each patient's values and target the best outcome possible given the patient's desires and his/her clinical condition. The aim of this position paper was to perform a review of the existing literature and to provide comprehensive recommendations on organizational, surgical, anaesthetic, and haemostatic strategies that can be used to provide optimal peri-operative blood management, reduce, or avoid blood transfusions and ultimately improve patient outcomes.

A Modern Approach to the Treatment of Traumatic Brain Injury

Background: Traumatic brain injury manifests itself in various forms, ranging from mild impairment of consciousness to severe coma and death. Traumatic brain injury remains one of the leading causes of morbidity and mortality. Currently, there is no therapy to reverse the effects associated with traumatic brain injury. New neuroprotective treatments for severe traumatic brain injury have not achieved significant clinical success. Methods: A literature review was performed to summarize the recent interdisciplinary findings on management of traumatic brain injury from both clinical and experimental perspective. Results: In the present review, we discuss the concepts of traditional and new approaches to treatment of traumatic brain injury. The recent development of different drug delivery approaches to the central nervous system is also discussed. Conclusions: The management of traumatic brain injury could be aimed either at the pathological mechanisms initiating the secondary brain injury or alleviating the symptoms accompanying the injury. In many cases, however, the treatment should be complex and include a variety of medical interventions and combination therapy.

Management of Head Trauma

Traumatic brain injury (TBI) represents a heterogenous spectrum of disease. It is essential to rapidly assess a patient's neurologic status and implement measures to prevent secondary brain injury. Intracranial hypertension, a common sequela of TBI, is managed in a tiered and systematic fashion, starting with the least invasive and moving toward the most invasive. TBI has long-lasting effects on patients and their families and represents a substantial financial and social influence on society. Research regarding the prognosis and treatment of TBI is essential to limit the influence of this widespread disease.

Dosing of tranexamic acid in trauma

PURPOSE OF REVIEW

Tranexamic acid is routinely used as part of the management of traumatic bleeding. The dose recommendation in trauma was extrapolated from other clinical settings and the results of pragmatic randomized trials rather than pharmaco-kinetic and -dynamic evaluations. The review addresses current evidence on dosing of tranexamic acid in traumatized patients with a focus on efficacy, safety and risk-benefit profile.

RECENT FINDINGS

A majority, but not all, of existing randomized clinical trials reports a reduction in mortality and/or blood loss with tranexamic acid administration. Increasing dose above the general recommendation (1 g bolus + 1 g infusion/8 h intravenously) has not been shown to further increase efficacy and could potentially increase side effects.

SUMMARY

The benefit of tranexamic acid as adjuvant therapy in the management of bleeding trauma patients on mortality and transfusion requirements is clear and well documented, being most effective if given early and to patients with clinical signs of hemorrhagic shock. Recent reports suggest that in some patients presenting with a shutdown of their fibrinolytic pathway the administration of tranexamic acid could be associated with an increased risk of thromboembolic events and poor outcomes. A more personalized approach based on bedside assessment of fibrinolytic activation and pharmacokinetic-based dose regimen should be developed moving forward.

THE NEUROENDOTHELIAL AXIS IN TRAUMATIC BRAIN INJURY: MECHANISMS OF MULTIORGAN DYSFUNCTION, NOVEL THERAPIES, AND FUTURE DIRECTIONS

ABSTRACT

Severe traumatic brain injury (TBI) often initiates a systemic inflammatory response syndrome, which can potentially culminate into multiorgan dysfunction. A central player in this cascade is endotheliopathy, caused by perturbations in homeostatic mechanisms governed by endothelial cells due to injury-induced coagulopathy, heightened sympathoadrenal response, complement activation, and proinflammatory cytokine release. Unique to TBI is the potential disruption of the blood-brain barrier, which may expose neuronal antigens to the peripheral immune system and permit neuroinflammatory mediators to enter systemic circulation, propagating endotheliopathy systemically. This review aims to provide comprehensive insights into the "neuroendothelial axis" underlying endothelial dysfunction after TBI, identify potential diagnostic and prognostic biomarkers, and explore therapeutic strategies targeting these interactions, with the ultimate goal of improving patient outcomes after severe TBI.

American Association for the Surgery of Trauma/American College of Surgeons Committee on Trauma: Clinical protocol for damage-control resuscitation for the adult trauma patient

ABSTRACT

Damage-control resuscitation in the care of critically injured trauma patients aims to limit blood loss and prevent and treat coagulopathy by combining early definitive hemorrhage control, hypotensive resuscitation, and early and balanced use of blood products (hemostatic resuscitation) and the use of other hemostatic agents. This clinical protocol has been developed to provide evidence-based recommendations for optimal damage-control resuscitation in the care of trauma patients with hemorrhage.

Guidelines for Prehospital Management of Traumatic Brain Injury 3rd Edition: Executive Summary

Prehospital care markedly influences outcome from traumatic brain injury, yet it remains highly variable. The Brain Trauma Foundation's guidelines informing prehospital care, first published in 2002, have sought to identify and disseminate best practices. Many of its recommendations relate to the management of airway, breathing and circulation, and infrastructure for this care. Compliance with the second edition of these guidelines has been associated with significantly improved survival. A working group developed evidence-based recommendations informing assessment, treatment, and transport decision-making relevant to the prehospital care of brain injured patients. A literature search spanning May 2005 to January 2022 supplemented data contained in the 2nd edition. Identified studies were assessed for quality and used to inform evidence-based recommendations. A total of 122 published articles formed the evidentiary base for this guideline update including 5 providing Class I evidence, 35 providing Class II evidence, and 98 providing Class III evidence for the various topics. Forty evidence-based recommendations were generated, 30 of which were strong and 10 of which were weak. In many cases, new evidence allowed guidelines from the 2nd edition to be strengthened. Development of guidelines on some new topics was possible including the prehospital administration of tranexamic acid. A management algorithm is also presented. These guidelines help to identify best practices for prehospital traumatic brain injury care, and they also identify gaps in knowledge which we hope will be addressed before the next edition.

Therapeutic review: The role of tranexamic acid in management of traumatic brain injury, nontraumatic intracranial hemorrhage, and aneurysmal subarachnoid hemorrhage

PURPOSE

To summarize current literature evaluating tranexamic acid in the management of intracranial bleeding associated with traumatic and nontraumatic brain injuries and implications for clinical practice.

SUMMARY

Intracranial hemorrhage, regardless of etiology, is associated with high morbidity and mortality. Tranexamic acid is an antifibrinolytic with anti-inflammatory properties shown to reduce mortality in trauma patients with extracranial injuries. In traumatic brain injury, a large randomized trial found no difference in outcomes when tranexamic acid was compared to placebo; however, subgroup analyses suggested that it may reduce head injury-related mortality in the context of mild-to-moderate injury if treatment occurs within 1 hour of symptom onset. More recent out-of-hospital data have disputed these findings and even suggested harm in severely injured patients. In spontaneous, nontraumatic intracranial hemorrhage, treatment with tranexamic acid did not result in a difference in functional status; however, rates of hematoma expansion, even though modest, were significantly reduced. In aneurysmal subarachnoid hemorrhage, tranexamic acid may prevent rebleeding, but has not led to improved outcomes or reduced mortality, and there is concern for increased incidence of delayed cerebral ischemia. Overall, tranexamic acid has not been shown to result in increased risk of thromboembolic complications across these classes of brain injury.

CONCLUSION

Despite its favorable safety profile overall, tranexamic acid does not seem to improve functional outcomes and cannot be routinely recommended. More data are needed to determine which head injury subpopulations are most likely to benefit from tranexamic acid and which patients are at increased risk for harm.

Factors that influence the administration of tranexamic acid (TXA) to trauma patients in prehospital settings: a systematic review

OBJECTIVE

In the UK there are around 5400 deaths annually from injury. Tranexamic acid (TXA) prevents bleeding and has been shown to reduce trauma mortality. However, only 5% of UK major trauma patients who are at risk of haemorrhage receive prehospital TXA. This review aims to examine the evidence regarding factors influencing the prehospital administration of TXA to trauma patients.

DESIGN

Systematic literature review.

DATA SOURCES

AMED, CENTRAL, CINAHL, Cochrane Database of Systematic Reviews, Conference Proceedings Citation Index-Science, Embase and MEDLINE were searched from January 2010 to 2020; searches were updated in June 2022.

CLINICALTRIALS

gov and OpenGrey were also searched and forward and backwards citation chasing performed.

ELIGIBILITY CRITERIA

All primary research reporting factors influencing TXA administration to trauma patients in the prehospital setting was included.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers performed the selection process, quality assessment and data extraction. Data were tabulated, grouped by setting and influencing factor and synthesised narratively.

RESULTS

Twenty papers (278 249 participants in total) were included in the final synthesis; 13 papers from civilian and 7 from military settings. Thirteen studies were rated as 'moderate' using the Effective Public Health Practice Project Quality Assessment Tool. Several common factors were identified: knowledge and skills; consequences and social influences; injury type (severity, injury site and mechanism); protocols; resources; priorities; patient age; patient sex.

CONCLUSIONS

This review highlights an absence of high-quality research. Preliminary evidence suggests a host of system and individual-level factors that may be important in determining whether TXA is administered to trauma patients in the prehospital setting.

FUNDING AND REGISTRATION

This review was supported by Research Capability Funding from the South Western Ambulance Service NHS Foundation Trust and the National Institute for Health Research Applied Research Collaboration South West Peninsula.

PROSPERO REGISTRATION NUMBER

CRD42020162943.

Acute Haemostatic Depletion and Failure in Patients with Traumatic Brain Injury (TBI): Pathophysiological and Clinical Considerations

BACKGROUND

Because of the aging population, the number of low falls in elderly people with pre-existing anticoagulation is rising, often leading to traumatic brain injury (TBI) with a social and economic burden. Hemostatic disorders and disbalances seem to play a pivotal role in bleeding progression. Interrelationships between anticoagulatoric medication, coagulopathy, and bleeding progression seem to be a promising aim of therapy.

METHODS

We conducted a selective search of the literature in databases like Medline (Pubmed), Cochrane Library and current European treatment recommendations using relevant terms or their combination.

RESULTS

Patients with isolated TBI are at risk for developing coagulopathy in the clinical course. Pre-injury intake of anticoagulants is leading to a significant increase in coagulopathy, so every third patient with TBI in this population suffers from coagulopathy, leading to hemorrhagic progression and delayed traumatic intracranial hemorrhage. In an assessment of coagulopathy, viscoelastic tests such as TEG or ROTEM seem to be more beneficial than conventional coagulation assays alone, especially because of their timely and more specific gain of information about coagulopathy. Furthermore, results of point-of-care diagnostic make rapid "goal-directed therapy" possible with promising results in subgroups of patients with TBI.

CONCLUSIONS

The use of innovative technologies such as viscoelastic tests in the assessment of hemostatic disorders and implementation of treatment algorithms seem to be beneficial in patients with TBI, but further studies are needed to evaluate their impact on secondary brain injury and mortality.

The efficacy of tranexamic acid treatment with different time and doses for traumatic brain injury: a systematic review and meta-analysis

OBJECTIVE

Tranexamic acid (TXA) plays a significant role in the treatment of traumatic diseases. However, its effectiveness in patients with traumatic brain injury (TBI) seems to be contradictory, according to the recent publication of several meta-analyses. We aimed to determine the efficacy of TXA treatment at different times and doses for TBI treatment.

METHODS

PubMed, MEDLINE, EMBASE, Cochrane Library, and Google Scholar were searched for randomized controlled trials that compared TXA and a placebo in adults and adolescents (≥ 15 years of age) with TBI up to January 31, 2022. Two authors independently abstracted the data and assessed the quality of evidence.

RESULTS

Of the identified 673 studies, 13 involving 18,675 patients met our inclusion criteria. TXA had no effect on mortality (risk ratio (RR) 0.99; 95% confidence interval (CI) 0.92-1.06), adverse events (RR 0.93, 95% Cl 0.76-1.14), severe TBI (Glasgow Coma Scale score from 3 to 8) (RR 0.99, 95% Cl 0.94-1.05), unfavorable Glasgow Outcome Scale (GOS < 4) (RR 0.96, 95% Cl 0.82-1.11), neurosurgical intervention (RR 1.11, 95% Cl 0.89-1.38), or rebleeding (RR 0.97, 95% Cl 0.82-1.16). TXA might reduce the mean hemorrhage volume on subsequent imaging (standardized mean difference, -0.35; 95% CI [-0.62, -0.08]).

CONCLUSION

TXA at different times and doses was associated with reduced mean bleeding but not with mortality, adverse events, neurosurgical intervention, and rebleeding. More research data is needed on different detection indexes and levels of TXA in patients with TBI, as compared to those not receiving TXA; although the prognostic outcome for all harm outcomes was not affected, the potential for harm was not ruled out.

TRIAL REGISTRATION

The review protocol was registered in the PROSPERO International Prospective Register of Systematic Reviews (CRD42022300484).

Coagulopathy in Isolated Traumatic Brain Injury: Myth or Reality

INTRODUCTION

Traumatic Brain Injury (TBI) has been shown to be associated with altered hemostasis and coagulopathy, that correlates with worsening secondary injury and clinical outcomes. Isolated Traumatic Brain Injury (iTBI), that is TBI without significant extracranial injuries, has also been shown to be associated with systemic coagulopathy and derangements in hemostasis.

METHODS

Literature Review.

RESULTS

Present your results in logical sequence in the text, tables, and figures, giving the main or most important findings first. Do not repeat all the data in the tables or figures in the text; emphasize or summarize only the most important observations. Provide data on all primary and secondary outcomes identified in the Methods section. Give numeric results not only as derivatives (e.g. percentages) but also as the absolute numbers from which the derivatives were calculated, and specify the statistical significance attached to them, if any.

DISCUSSION

In this review, we provide an overview of the pathophysiology of the hemostatic disturbances caused by iTBI, review key clinical findings and discrepancies in the way this question has been approached, describe the use and role of global viscoelastic assays such as the thromboelastrogram, and detail principles for reversal of pre-injury blood thinners.

CONCLUSIONS

iTBI is clearly associated with the development of coagulopathy, but the extent to which it occurs is confounded by the fact that many of the studies have included patients with moderate extracranial trauma into the iTBI category. The coagulopathy itself has been better studied in preclinical models, and the mechanisms driving it suggest a pattern consistent with disseminated intravascular coagulation with hyperfibrinolysis. We provide pragmatic clinical takeaways and suggestions for future research.

Antifibrinolytics in the treatment of traumatic brain injury

PURPOSE OF REVIEW

Traumatic brain injury (TBI) is a leading cause of trauma-related deaths, and pharmacologic interventions to limit intracranial bleeding should improve outcomes. Tranexamic acid reduces mortality in injured patients with major systemic bleeding, but the effects of antifibrinolytic drugs on outcomes after TBI are less clear. We therefore summarize recent evidence to guide clinicians on when (not) to use antifibrinolytic drugs in TBI patients.

RECENT FINDINGS

Tranexamic acid is the only antifibrinolytic drug that has been studied in patients with TBI. Several recent studies failed to conclusively demonstrate a benefit on survival or neurologic outcome. A large trial with more than 12 000 patients found no significant effect of tranexamic acid on head-injury related death, all-cause mortality or disability across the overall study population, but observed benefit in patients with mild to moderate TBI. Observational evidence signals potential harm in patients with isolated severe TBI.

SUMMARY

Given that the effect of tranexamic acid likely depends on a variety of factors, it is unlikely that a 'one size fits all' approach of administering antifibrinolytics to all patients will be helpful. Tranexamic acid should be strongly considered in patients with mild to moderate TBI and should be avoided in isolated severe TBI.

Prehospital Intubation of Patients with Severe Traumatic Brain Injury: A Dutch Nationwide Trauma Registry Analysis

ObjectivePatients with severe traumatic brain injury (TBI) are commonly intubated during prehospital treatment despite a lack of evidence that this is beneficial. Accumulating evidence even suggests that prehospital intubation may be hazardous, in particular when performed by inexperienced EMS clinicians. To expand the limited knowledge base, we studied the relationship between prehospital intubation and hospital mortality in patients with severe TBI in a large Dutch trauma database. We specifically hypothesized that the relationship differs depending on whether a physician-based emergency medical service (EMS) was involved in the treatment, as opposed to intubation by paramedics.MethodsA retrospective analysis was performed using the Dutch Nationwide Trauma Registry that includes all trauma patients in the Netherlands who are admitted to any hospital with an emergency department. All patients treated for severe TBI (Head Abbreviated Injury Scale score ≥4) between January 2015 and December 2019 were selected. Multivariable logistic regression was used to assess the relationship between prehospital intubation and mortality while adjusting for potential confounders. An interaction term between prehospital intubation and the involvement of physician-based EMS was added to the model. Complete case analysis as well as multiple imputation were performed.Results8946 patients (62% male, median age 63 years) were analyzed. The hospital mortality was 26.4%. Overall, a relationship between prehospital intubation and higher mortality was observed (complete case: OR 1.86, 95%CI 1.35-2.57, P < 0.001; multiple imputation: OR 1.92, 95%CI 1.56-2.36, P < 0.001). Adding the interaction revealed that the relationship of prehospital intubation may depend on whether physician-based EMS is involved in the treatment (complete case: P = 0.044; multiple imputation: P = 0.062). Physician-based EMS involvement attenuated but did not completely remove the detrimental association between prehospital intubation and mortality.ConclusionThe data do not support the common practice of prehospital intubation. The effect of prehospital intubation on mortality might depend on EMS clinician experience, and it seems prudent to involve prehospital personnel well proficient in prehospital intubation whenever intubation is potentially required. The decision to perform prehospital intubation should not merely be based on the largely unsupported dogma that it is generally needed in severe TBI, but should rather individually weigh potential benefits and harms.

Appraising the use of tranexamic acid in traumatic and non‐traumatic intracranial hemorrhage: A narrative review

Recently there has been increasing interest and debate on the use of tranexamic acid (TXA), an antifibrinolytic drug, in both traumatic and non‐traumatic intracranial hemorrhage. In this review we aim to discuss recent investigations looking at TXA in traumatic brain injury (TBI) and different categories of spontaneous intracranial hemorrhage. We also discuss differences between setting (hospital vs pre‐hospital), dosing and timing strategies, and other logistical challenges surrounding optimal use of TXA for isolated intracranial hemorrhage. Last, we hope to provide guidance for clinicians when considering the use of TXA in a patient with traumatic or non‐traumatic intracranial hemorrhage based on appraisal of the available literature as well as some potential ideas for future research in this area.

Management of Severe Traumatic Brain Injury in Pediatric Patients

The optimal management of severe traumatic brain injury (TBI) in the pediatric population has not been well studied. There are a limited number of research articles studying the management of TBI in children. Given the prevalence of severe TBI in the pediatric population, it is crucial to develop a reference TBI management plan for this vulnerable population. In this review, we seek to delineate the differences between severe TBI management in adults and children. Additionally, we also discuss the known molecular pathogenesis of TBI. A better understanding of the pathophysiology of TBI will inform clinical management and development of therapeutics. Finally, we propose a clinical algorithm for the management and treatment of severe TBI in children using published data.

Current Clinical Trials in Traumatic Brain Injury

Traumatic brain injury (TBI) is one of the leading causes of morbidity, disability and mortality across all age groups globally. Currently, only palliative treatments exist, but these are suboptimal and do little to combat the progressive damage to the brain that occurs after a TBI. However, multiple experimental treatments are currently available that target the primary and secondary biochemical and cellular changes that occur after a TBI. Some of these drugs have progressed to clinical trials and are currently being evaluated for their therapeutic benefits in TBI patients. The aim of this study was to identify which drugs are currently being evaluated in clinical trials for TBI. A search of ClinicalTrials.gov was performed on 3 December 2021 and all clinical trials that mentioned “TBI” OR “traumatic brain injury” AND “drug” were searched, revealing 362 registered trials. Of the trials, 46 were excluded due to the drug not being mentioned, leaving 138 that were completed and 116 that were withdrawn. Although the studies included 267,298 TBI patients, the average number of patients per study was 865 with a range of 5–200,000. Of the completed studies, 125 different drugs were tested in TBI patients but only 7 drugs were used in more than three studies, including amantadine, botulinum toxin A and tranexamic acid (TXA). However, previous clinical studies using these seven drugs showed variable results. The current study concludes that clinical trials in TBI have to be carefully conducted so as to reduce variability across studies, since the severity of TBI and timing of therapeutic interventions were key aspects of trial success.

The role of tranexamic acid in traumatic brain injury

Evidence from recent trials evaluating efficacy of antifibrinolytic agents in the context of traumatic brain injury may lead to changes in the management of patients with traumatic brain injury. Tranexamic acid (TXA) reduces the proteolytic action of plasmin on fibrin clots, resulting in an inhibition of fibrinolysis and stabilisation of established blood clots. There has been significant interest in use of the drug as a therapeutic agent in the context of severe haemorrhage; however, considerable controversies regarding its efficacy remain. A number of trials have demonstrated a small but significant decrease in mortality following its administration, but the results have been somewhat inconsistent and may not be generalisable. The results of the CRASH-3 trial were that there was no statistical difference in the number of traumatic brain injury related deaths (18.5% with TXA and 19.8% with placebo; relative risk [RR] 0·94; 95% confidence interval [CI] 0·86-1·02). Nonetheless, there was a subgroup of patients for whom TXA appeared to provide benefit, and this was in patients with mild and moderate injury (with a Glasgow Coma Score > 8). This is potentially a very important finding that may have huge potential implications; however, we believe it does not currently provide indisputable evidence to support the administration of TXA to all patients with TBI. Further work is required to better define the subset of patients who may benefit as well as to evaluate the long-term functional benefit in order to determine which types of severe traumatic brain injury patients would derive more benefits than harms from TXA.

Schädelhirntrauma: präklinische Gabe von Tranexamsäure erhöht Mortalitätsrate

Tranexamsäure ist ein Antifibrinolytikum und kann im präklinischen Setting das Blutungsrisiko reduzieren. Obgleich es über seine Wirkung bei schweren Schädelhirntraumata (SHT) widersprüchliche Daten gibt, könnte eine frühe Gabe Hirnblutungen eindämmen. Bossers und sein Team haben hier angesetzt und untersuchen in ihrer Beobachtungsstudie den Zusammenhang zwischen präklinischer Gabe von Tranexamsäure und der Sterblichkeit nach schwerem SHT.

Controversies and evidence gaps in the early management of severe traumatic brain injury: back to the ABCs

Traumatic brain injury (TBI) accounts for around 30% of all trauma-related deaths. Over the past 40 years, TBI has remained a major cause of mortality after trauma. The primary injury caused by the injurious mechanical force leads to irreversible damage to brain tissue. The potentially preventable secondary injury can be accentuated by addressing systemic insults. Early recognition and prompt intervention are integral to achieve better outcomes. Consequently, surgeons still need to be aware of the basic yet integral emergency management strategies for severe TBI (sTBI). In this narrative review, we outlined some of the controversies in the early care of sTBI that have not been settled by the publication of the Brain Trauma Foundation’s 4th edition guidelines in 2017. The topics covered included the following: mode of prehospital transport, maintaining airway patency while securing the cervical spine, achieving adequate ventilation, and optimizing circulatory physiology. We discuss fluid resuscitation and blood product transfusion as components of improving circulatory mechanics and oxygen delivery to injured brain tissue. An outline of evidence-based antiplatelet and anticoagulant reversal strategies is discussed in the review. In addition, the current evidence as well as the evidence gaps for using tranexamic acid in sTBI are briefly reviewed. A brief note on the controversial emergency surgical interventions for sTBI is included. Clinicians should be aware of the latest evidence for sTBI. Periods between different editions of guidelines can have an abundance of new literature that can influence patient care. The recent advances included in this review should be considered both for formulating future guidelines for the management of sTBI and for designing future clinical studies in domains with clinical equipoise.

Early thrombocytopenia is associated with an increased risk of mortality in patients with traumatic brain injury treated in the intensive care unit: a Finnish Intensive Care Consortium study

BACKGROUND

Coagulopathy after traumatic brain injury (TBI) is associated with poor prognosis.

PURPOSE

To assess the prevalence and association with outcomes of early thrombocytopenia in patients with TBI treated in the intensive care unit (ICU).

METHODS

This is a retrospective multicenter study of adult TBI patients admitted to ICUs during 2003-2019. Thrombocytopenia was defined as a platelet count < 100 × 10⁹/L during the first day. The association between thrombocytopenia and hospital and 12-month mortality was tested using multivariable logistic regression, adjusting for markers of injury severity.

RESULTS

Of 4419 patients, 530 (12%) had early thrombocytopenia. In patients with thrombocytopenia, hospital and 12-month mortality were 26% and 48%, respectively; in patients with a platelet count > 100 × 10⁹/L, they were 9% and 22%, respectively. After adjusting for injury severity, a higher platelet count was associated with decreased odds of hospital mortality (OR 0.998 per unit, 95% CI 0.996-0.999) and 12-month mortality (OR 0.998 per unit, 95% CI 0.997-0.999) in patients with moderate-to-severe TBI. Compared to patients with a normal platelet count, patients with thrombocytopenia not receiving platelet transfusion had an increased risk of 12-month mortality (OR 2.2, 95% CI 1.6-3.0), whereas patients with thrombocytopenia receiving platelet transfusion did not (OR 1.0, 95% CI 0.6-1.7).

CONCLUSION

Early thrombocytopenia occurs in approximately one-tenth of patients with TBI treated in the ICU, and it is an independent risk factor for mortality in patients with moderate-to-severe TBI. Further research is necessary to determine whether this is modifiable by platelet transfusion.

Perioperative Management of Polytrauma Patients with Severe Traumatic Brain Injury Undergoing Emergency Extracranial Surgery: A Narrative Review

Managing the acute phase after a severe traumatic brain injury (TBI) with polytrauma represents a challenging situation for every trauma team member. A worldwide variability in the management of these complex patients has been reported in recent studies. Moreover, limited evidence regarding this topic is available, mainly due to the lack of well-designed studies. Anesthesiologists, as trauma team members, should be familiar with all the issues related to the management of these patients. In this narrative review, we summarize the available evidence in this setting, focusing on perioperative brain protection, cardiorespiratory optimization, and preservation of the coagulative function. An overview on simultaneous multisystem surgery (SMS) is also presented.

Coagulopathy and Progression of Intracranial Hemorrhage in Traumatic Brain Injury: Mechanisms, Impact, and Therapeutic Considerations

BACKGROUND

Traumatic brain injury (TBI) remains one of the most challenging health and socioeconomic problems of our times. Clinical courses may be complicated by hemostatic abnormalities either pre-existing or developing with TBI.

OBJECTIVE

To review frequencies, patterns, mechanisms, novel approaches to diagnostics, treatment, and outcomes of hemorrhagic progression and coagulopathy after TBI.

METHODS

Selective review of the literature in the databases Medline (PubMed) and Cochrane Reviews using different combinations of the relevant search terms was conducted.

RESULTS

Of the patients, 20% with isolated TBI display laboratory coagulopathy upon hospital admission with profound effect on morbidity and mortality. Preinjury use of antithrombotic agents may be associated with higher rates of hemorrhagic progression and delayed traumatic intracranial hemorrhage. Further testing may display various changes affecting platelet function/numbers, pro- and/or anticoagulant factors, and fibrinolysis as well as interactions between brain tissues, vascular endothelium, mechanisms of inflammation, and blood flow dynamics. The nature of hemostatic disruptions after TBI remains elusive but current evidence suggests the presence of both a hyper- and hypocoagulable state with possible overlap and lack of distinction between phases and states. More "global" hemostatic assays, eg, viscoelastic and thrombin generation tests, may provide more detailed and timely information on the overall hemostatic potential thereby allowing early "goal-directed" therapies.

CONCLUSION

Whether timely and targeted management of hemostatic abnormalities after TBI can protect against secondary brain injury and thereby improve outcomes remains elusive. Innovative technologies for diagnostics and monitoring offer windows of opportunities for precision medicine approaches to managing TBI.

The effect of prehospital tranexamic acid on outcome in polytrauma patients with associated severe brain injury

INTRODUCTION

Tranexamic acid (TXA) has shown to be beneficial in selected patients with hemorrhagic shock. Recently, TXA has gained interest in isolated traumatic brain injury (TBI) patients with variable results. There are limited data on TXA in polytrauma with associated TBI. This study investigated the role of TXA in severely injured patients with associated severe TBI.

METHODS

A 7.5-year prospective cohort study was performed to investigate the relation between prehospital TXA and mortality in consecutive trauma patients with associated severe TBI (Abbreviated Injury Scale (AIS)head ≥ 3) admitted to a Level-1 Trauma Center ICU. Indication for prehospital TXA administration was (suspicion of) hemorrhagic shock, and/or systolic blood pressure (SBP) ≤ 90 mmHg. Demographics, data on physiology, resuscitation, and outcomes were prospectively collected.

RESULTS

Two hundred thirty-four patients (67% males) with median age of 49 years and ISS 33 (98% blunt injuries) were included. Thirteen patients (6%) developed thromboembolic complications; mortality rate was 24%. Fifty-one percent of patients received prehospital TXA. TXA patients were younger, had more deranged physiology on arrival, and received more crystalloids and blood products ≤ 24 h. There was, however, no difference in overall outcome between TXA patients and no-TXA patients.

CONCLUSIONS

Despite having a more deranged physiology TXA patients had similar outcome compared to no-TXA patients who were much older. Thromboembolic complication rate was low. Prehospital tranexamic acid has no evident effect on outcome in polytrauma patients with associated critical brain injury.

Prehospital Tranexamic Acid (TXA) in Patients with Traumatic Brain Injury (TBI)

Traumatic brain injury (TBI) remains a significant medical and socioeconomic challenge. The initial injury may be complicated by haemostatic derangements leading to exacerbation of lesions and haemorrhagic progression. The results from the CRASH-3 trial have promoted the implementation of the antifibrinolytic tranexamic acid (TXA) into prehospital Emergency Medical Services (EMS) protocols. Very recently, the efficacy and safety of early out-of-hospital TXA compared to placebo was assessed in patients with moderate or severe TBI in a prospective, multicenter phase II trial, e.g. "The Prehospital TXA for TBI"-trial. Simultaneously, the results from a retrospective analysis of prospectively collected observational data into the Dutch pre-hospital TBI database were published which had assessed whether prehospital administration of TXA may be associated with mortality and functional outcomes in patients with severe TBI. Both studies are reviewed against their limitations and windows of opportunity are highlighted.

Tranexamic acid in non-traumatic intracranial bleeding: a systematic review and meta-analysis

Non-traumatic intracranial bleeding (NTIB), comprising subarachnoid hemorrhage (SAH) and intra-cranial bleeding (ICH) is a significant public health concern. Tranexamic acid (TXA) is a promising treatment with benefits yet to be fully demonstrated. We conducted a systematic review and meta-analysis on the impact of TXA on mortality in NTIB. We searched the PubMed, Cochrane Library, Google Scholar and ScienceDirect databases for studies reporting mortality data following the use of TXA in NTIB for comparisons with a control group. We computed random-effect meta-analysis on estimates of risk and sensitivity analyses. We computed meta-regression to examine the putative effects of the severity of NTIB, sociodemographic data (age, sex), and publication date. Among potentially 10,008 articles, we included 15 studies representing a total of 4883 patients: 2455 receiving TXA and 2428 controls; 1110 died (23%) during the follow-up. The meta-analysis demonstrated a potential of 22% decrease in mortality for patients treated by TXA (RR = 0.78, 95%CI 0.58-0.98, p = 0.002). Meta-regression did not demonstrate any influence of the severity of NTIB, age, sex, length of treatment or date of publication. Sensitivity analyses confirmed benefits of TXA on mortality. TXA appears to be a therapeutic option to reduce non-traumatic intracranial bleeding mortality, particularly in patients with SAH.

Civilian Firearm-Inflicted Brain Injury: Coagulopathy, Vascular Injuries, and Triage

PURPOSE OF REVIEW

Civilian firearm-inflicted penetrating brain injury (PBI) carries high morbidity and mortality. Concurrently, the evidence base guiding management decisions remains limited. Faced with large volume of PBI patients, we have made observations in relation to coagulopathy and cerebrovascular injuries. We here review this literature in addition to the question about early prognostication as it may inform neurosurgical decision-making.

RECENT FINDINGS

The triad of coagulopathy, low motor score, and radiographic compression of basal cisterns comprises a phenotype of injury with exceedingly high mortality. PBI leads to high rates of cerebral arterial and venous injuries, and projectile trajectory is emerging as an independent predictor of outcome. The combination of coagulopathy with cerebrovascular injury creates a specific endophenotype. The nature and role of coagulopathy remain to be deciphered, and consideration to the use of tranexamic acid should be given. Prospective controlled trials are needed to create clinical evidence free of patient selection bias.

Genetic Variants Associated With Intraparenchymal Hemorrhage Progression After Traumatic Brain Injury

IMPORTANCE

Intracerebral hemorrhage progression is associated with unfavorable outcome after traumatic brain injury (TBI). No effective treatments are currently available. This secondary injury process reflects an extreme form of vasogenic edema and blood-brain barrier breakdown. The sulfonylurea receptor 1-transient receptor potential melastatin 4 (SUR1-TRPM4) cation channel is a key underlying mechanism. A phase 2 trial of SUR1-TRPM4 inhibition in contusional TBI is ongoing, and a phase 3 trial is being designed. Targeted identification of patients at increased risk for hemorrhage progression may inform prognostication, trial design (including patient selection), and ultimately treatment response.

OBJECTIVE

To determine whether ABCC8 (SUR1) and TRPM4 genetic variability are associated with intraparenchymal hemorrhage (IPH) progression after severe TBI, based on the putative involvement of the SUR1-TRPM4 channel in this pathophysiology.

DESIGN, SETTING, AND PARTICIPANTS

In this genetic association study, DNA was extracted from 416 patients with severe TBI prospectively enrolled from a level I trauma academic medical center from May 9, 2002, to August 8, 2014. Forty ABCC8 and TRPM4 single-nucleotide variants (SNVs) were genotyped (multiplex, unbiased). Data were analyzed from January 7, 2020, to May 3, 2021.

MAIN OUTCOMES AND MEASURES

Primary analyses addressed IPH progression at 6, 24, and 120 hours in patients without acute craniectomy (n = 321). Multivariable regressions and receiver operating characteristic curves assessed SNV and haplotype associations with progression. Spatial modeling and functional predictions were determined using standard software.

RESULTS

Of the 321 patients included in the analysis (mean [SD] age, 37.0 [16.3] years; 247 [76.9%] male), IPH progression occurred in 102. Four ABCC8 SNVs were associated with markedly increased odds of progression (rs2237982 [odds ratio (OR), 2.60-3.80; 95% CI, 1.14-5.90 to 1.80-8.02; P = .02 to P < .001], rs2283261 [OR, 3.37-4.77; 95% CI, 1.07-10.77 to 1.89-12.07; P = .04 to P = .001], rs3819521 [OR, 2.96-3.92; 95% CI, 1.13-7.75 to 1.42-10.87; P = .03 to P = .009], and rs8192695 [OR, 3.06-4.95; 95% CI, 1.02-9.12 to 1.67-14.68]; P = .03-.004). These are brain-specific expression quantitative trait loci (eQTL) associated with increased ABCC8 messenger RNA levels. Regulatory annotations revealed promoter and enhancer marks and strong and/or active brain-tissue transcription, directionally consistent with increased progression. Three SNVs (rs2283261, rs2237982, and rs3819521) in this cohort have been associated with intracranial hypertension. Four TRPM4 SNVs were associated with decreased IPH progression (rs3760666 [OR, 0.40-0.49; 95% CI, 0.19-0.86 to 0.27-0.89; P = .02 to P = .009], rs1477363 [OR, 0.40-0.43; 95% CI, 0.18-0.88 to 0.23-0.81; P = .02 to P = .006], rs10410857 [OR, 0.36-0.41; 95% CI, 0.20-0.67 to 0.20-0.85; P = .02 to P = .001], and rs909010 [OR, 0.27-0.40; 95% CI, 0.12-0.62 to 0.16-0.58; P = .002 to P < .001]). Significant SNVs in both genes cluster downstream, flanking exons encoding the receptor site and SUR1-TRPM4 binding interface. Adding genetic variation to clinical models improved receiver operating characteristic curve performance from 0.6959 to 0.8030 (P = .003).

CONCLUSIONS AND RELEVANCE

In this genetic association study, 8 ABCC8 and TRPM4 SNVs were associated with IPH progression. Spatial clustering, brain-specific eQTL, and regulatory annotations suggest biological plausibility. These findings may have important implications for neurocritical care risk stratification, patient selection, and precision medicine, including an upcoming phase 3 trial design for SUR1-TRPM4 inhibition in severe TBI.

Does Liberal Prehospital and In-Hospital Tranexamic Acid Influence Outcome in Severely Injured Patients? A Prospective Cohort Study

Background

Early hemorrhage control is important in trauma-related death prevention. Tranexamic acid (TXA) has shown to be beneficial in patients in hemorrhagic shock, although widespread adoption might result in incorrect TXA administration leading to increased morbidity and mortality.

Methods

A 7-year prospective cohort study with consecutive trauma patients admitted to a Level-1 Trauma Center ICU was performed to investigate administration of both pre- and in-hospital TXA and its relation to morbidity and mortality. Indication for prehospital and in-hospital TXA administration was (suspicion of) hemorrhagic shock, and/or systolic blood pressure (SBP) ≤ 90 mmHg. Demographics, data on physiology, resuscitation and outcomes were prospectively collected.

Results

Four hundred and twenty-two patients (71% males, median ISS 29, 95% blunt injuries) were included. Even though TXA patients were more severely injured with more deranged physiology, no differences in outcome were noted. Overall, thrombo-embolic complication rate was 8%. In half the patients, hemorrhagic shock was the indication for prehospital TXA, whereas 79% of in-hospital TXA was given based on suspicion of hemorrhagic shock. Thirteen percent of patients with SBP ≤ 90 mmHg in ED received no TXA at all. Based on SBP alone, 22% of prehospital TXA and 25% of in-hospital TXA were justified.

Conclusions

Despite being more severely injured, TXA patients had similar outcome compared to patients without TXA. Thrombo-embolic complication rate was low despite liberal use of both prehospital and in-hospital TXA. Caution should be exercised in selecting patients for TXA, although this might be challenging based on SBP alone in patients who do not yet show signs of deranged physiology on arrival in ED.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00268-021-06143-y.