Enoxaparin in the treatment of severe traumatic brain injury: A randomized clinical trial

Post-Traumatic Cerebral Venous Sinus Thrombosis (PtCVST) Resulting in Increased Intracranial Pressure during Early Post-Traumatic Brain Injury Period: Case Report and Narrative Literature Review

Post-traumatic cerebral venous sinus thrombosis (ptCVST) often remains underdiagnosed due to the non-specific nature of clinical signs, commonly mimicking severe traumatic brain injury (TBI) manifestations. Early recognition of this rare and potentially life-threatening complication is crucial for the effective management of severe TBI patients in Intensive Care. The present study reports the case of a 66-year-old male who was transferred to the emergency department due to moderate TBI. Initial emergency brain computed tomography (CT) scans revealed certain traumatic lesions, not necessitating any urgent neurosurgical intervention. During his stay in an Intensive Care Unit (ICU), multiple transient episodes of intracranial pressure (ICP) values were managed conservatively, and through placement of an external ventricular drain. Following a series of CT scans, there was a continuous improvement of the initial traumatic hemorrhagic findings despite his worsening clinical condition. This paradox raised suspicion for ptCVST, and a brain CT venography (CTV) was carried out, which showed venous sinus thrombosis close to a concomitant skull fracture. Therapeutic anticoagulant treatment was administered. The patient was discharged with an excellent neurological status. To date, there are no clearly defined guidelines for medical and/or surgical management of patients presenting with ptCVST. Therapy is mainly based on intracranial hypertension control and the maintenance of normal cerebral perfusion pressure (CCP) in the ICU. The mismatch between clinical and imaging findings in patients with TBI and certain risk factors raises the suspicion of ptCVST.

Venous thromboembolism chemoprophylaxis in geriatric trauma patients with isolated severe traumatic brain injury

PURPOSE

Low-molecular-weight-heparin (LMWH) has been shown to be associated with a decreased risk of venous thromboembolism (VTE) and mortality compared to unfractionated heparin (UH) in severe traumatic brain injury (TBI). The aim of this study was to see if this association persists among a subset of patients, namely elderly patients with isolated TBI.

METHODS

This Trauma Quality Improvement Project (TQIP) database study included patients ≥ 65 years old with severe TBI (Abbreviated injury score [AIS] ≥ 3) that received either LMWH or UH for VTE prophylaxis. Patients with associated severe injuries (extracranial AIS ≥ 3), transferals, deaths < 72-h, hospitalization < 2 days, VTE chemoprophylaxis other than UH or LMWH, or with a history of bleeding diathesis were excluded. The association between VTE, deep vein thrombosis (DVT), and pulmonary embolism (PE) with VTE chemoprophylaxis was analyzed with multivariable analysis, subset analyses of different grades of AIS-head injury, and a 1:1 matched LWMH:UH cohort of patients.

RESULTS

Out of 14,926 patients, 11,036 (73.9%) received LMWH. Multivariate analysis showed that patients receiving LMWH had a decreased risk of mortality (OR 0.81, 95% CI 0.67-0.97, p < 0.001) but a similar risk of VTE (OR 0.83, 95% CI 0.63-1.08). Analysis according to head-AIS showed that LMWH was associated with a decreased risk of PE in patients AIS-3 but not in AIS 4 or 5. In a 1:1 matched cohort of LMWH:UH patients, the risk of PE, DVT and VTE were all similar but LMWH continued to be associated with a decreased risk of mortality (OR 0.81, CI 0.67-0.97, p = 0.023).

CONCLUSION

LMWH was associated with a decreased risk of overall mortality and reduced risk of PE compared to UH among geriatric patients with a severe head injury.

Roles and therapeutic potential of different extracellular vesicle subtypes on traumatic brain injury

Traumatic brain injury (TBI) is a leading cause of injury-related disability and death around the world, but the clinical stratification, diagnosis, and treatment of complex TBI are limited. Due to their unique properties, extracellular vesicles (EVs) are emerging candidates for being biomarkers of traumatic brain injury as well as serving as potential therapeutic targets. However, the effects of different extracellular vesicle subtypes on the pathophysiology of traumatic brain injury are very different, or potentially even opposite. Before extracellular vesicles can be used as targets for TBI therapy, it is necessary to classify different extracellular vesicle subtypes according to their functions to clarify different strategies for EV-based TBI therapy. The purpose of this review is to discuss contradictory effects of different EV subtypes on TBI, and to propose treatment ideas based on different EV subtypes to maximize their benefits for the recovery of TBI patients. Video Abstract.

Mortality of Surgically Treated Neurotrauma in Elderly Patients and the Development of a Prediction Score: Geriatric Neurotrauma Mortality Score

BACKGROUND

As the population worldwide is aging, the need for surgery in elderly patients with neurotrauma is increasing. The aim of this study was to compare the outcome of elderly patients undergoing surgery for neurotrauma with younger patients and to identify the risk factors for mortality.

METHODS

We retrospectively analyzed consecutive patients undergoing craniotomy or craniectomy for neurotrauma at our institution from 2012 to 2019. Patients were divided into two groups (≥70 years or <70 years) and compared. The primary outcome was the 30-day mortality rate. Potential risk factors for 30-day mortality were assessed in a uni- and multivariate regression model for both age groups, forming the basis of a 30-day mortality prediction score.

RESULTS

We included 163 consecutive patients (average age 57.98 ± 19.87 years); 54 patients were ≥70 years. Patients ≥70 years showed a significantly better median preoperative Glasgow Coma Scale (GCS) score compared with young patients (P < 0.001), and fewer pupil asymmetry (P = 0.001), despite having a higher Marshall score (P = 0.07) at admission. Multivariate regression analysis identified low pre- and postoperative GCS scores and the lack of prompt postoperative prophylactic low-molecular-weight heparin treatment as risk factors for 30-day mortality. Our score showed moderate accuracy in predicting 30-day mortality with an area under the curve of 0.76.

CONCLUSIONS

Elderly patients after neurotrauma present with a better GCS at admission despite having more severe radiographic injuries. Mortality and favorable outcome rates are comparable between the age groups.

A Systematic Review and Meta-Analysis on the Therapeutic Efficacy of Heparin and Low Molecular Weight Heparins in Animal Studies of Traumatic Brain Injury

The identification of effective pharmacotherapies for traumatic brain injury (TBI) remains a major challenge. Treatment with heparin and its derivatives is associated with neuroprotective effects after experimental TBI; however, the optimal dosage and method of administration, modes of action, and effects on hemorrhage remain unclear. Therefore, this review aimed to systematically evaluate, analyze, and summarize the available literature on the use of heparin and low molecular weight heparins (LMWHs) as treatment options for experimental TBI. We searched two online databases (PubMed and ISI Web of Science) to identify relevant studies. Data pertaining to TBI paradigm, animal subjects, drug administration, and all pathological and behavior outcomes were extracted. Eleven studies met our pre-specified inclusion criteria, and for outcomes with sufficient numbers, data from seven publications were analyzed in a weighted mean difference meta-analysis using a random-effects model. Study quality and risk of bias were also determined. Meta-analysis revealed that heparin and its derivatives decreased brain edema, leukocyte rolling, and vascular permeability, and improved neurological function. Further, treatment did not aggravate hemorrhage. These findings must be interpreted with caution, however, because they were determined from a limited number of studies with substantial heterogeneity. Also, overall study quality was low based on absences of data reporting, and potential publication bias was identified. Importantly, we found that there are insufficient data to evaluate the variables we had hoped to investigate. The beneficial effects of heparin and LMWHs, however, suggest that further pre-clinical studies are warranted.

Effect of drug therapy on nerve repair of moderate-severe traumatic brain injury: A network meta-analysis

Objective: This network meta-analysis aimed to explore the effect of different drugs on mortality and neurological improvement in patients with traumatic brain injury (TBI), and to clarify which drug might be used as a more promising intervention for treating such patients by ranking.

Methods: We conducted a comprehensive search from PubMed, Medline, Embase, and Cochrane Library databases from the establishment of the database to 31 January 2022. Data were extracted from the included studies, and the quality was assessed using the Cochrane risk-of-bias tool. The primary outcome measure was mortality in patients with TBI. The secondary outcome measures were the proportion of favorable outcomes and the occurrence of drug treatment–related side effects in patients with TBI in each drug treatment group. Statistical analyses were performed using Stata v16.0 and RevMan v5.3.0.

Results: We included 30 randomized controlled trials that included 13 interventions (TXA, EPO, progesterone, progesterone + vitamin D, atorvastatin, beta-blocker therapy, Bradycor, Enoxaparin, Tracoprodi, dexanabinol, selenium, simvastatin, and placebo). The analysis revealed that these drugs significantly reduced mortality in patients with TBI and increased the proportion of patients with favorable outcomes after TBI compared with placebo. In terms of mortality after drug treatment, the order from the lowest to the highest was progesterone + vitamin D, beta-blocker therapy, EPO, simvastatin, Enoxaparin, Bradycor, Tracoprodi, selenium, atorvastatin, TXA, progesterone, dexanabinol, and placebo. In terms of the proportion of patients with favorable outcomes after drug treatment, the order from the highest to the lowest was as follows: Enoxaparin, progesterone + vitamin D, atorvastatin, simvastatin, Bradycor, EPO, beta-blocker therapy, progesterone, Tracoprodi, TXA, selenium, dexanabinol, and placebo. In addition, based on the classification of Glasgow Outcome Scale (GOS) scores after each drug treatment, this study also analyzed the three aspects of good recovery, moderate disability, and severe disability. It involved 10 interventions and revealed that compared with placebo treatment, a higher proportion of patients had a good recovery and moderate disability after treatment with progesterone + vitamin D, Bradycor, EPO, and progesterone. Meanwhile, the proportion of patients with a severe disability after treatment with progesterone + vitamin D and Bradycor was also low.

Conclusion: The analysis of this study revealed that in patients with TBI, TXA, EPO, progesterone, progesterone + vitamin D, atorvastatin, beta-blocker therapy, Bradycor, Enoxaparin, Tracoprodi, dexanabinol, selenium, and simvastatin all reduced mortality and increased the proportion of patients with favorable outcomes in such patients compared with placebo. Among these, the progesterone + vitamin D had not only a higher proportion of patients with good recovery and moderate disability but also a lower proportion of patients with severe disability and mortality. However, whether this intervention can be used for clinical promotion still needs further exploration.

Proteoglycans and Glycosaminoglycans in Central Nervous System Injury

The brain and spinal cord constitute the central nervous system (CNS), which when injured, can be exceedingly devastating. The mechanistic roles of proteoglycans (PGs) and their glycosaminoglycan (GAG) side chains in such injuries have been extensively studied. CNS injury immediately alters endothelial and extracellular matrix (ECM) PGs and GAGs. Subsequently, these alterations contribute to acute injury, post-injury fibrosis, and post-injury repair. These effects are central to the pathophysiology of CNS injury. This review focuses on the importance of PGs and GAGs in multiple forms of injury including traumatic brain injury, spinal cord injury, and stroke. We highlight the causes and consequences of degradation of the PG and GAG-enriched endothelial glycocalyx in early injury and discuss the pleiotropic roles of PGs in neuroinflammation. We subsequently evaluate the dualistic effects of PGs on recovery: both PG/GAG-mediated inhibition and facilitation of repair. We then report promising therapeutic strategies that may prove effective for repair of CNS injury including PG receptor inhibition, delivery of endogenous, pro-repair PGs and GAGs, and direct degradation of pathologic GAGs. Last, we discuss importance of two PG- and GAG-containing ECM structures (synapses and perineuronal nets) in CNS injury and recovery.

A Retrospective Analysis of Randomized Controlled Trials on Traumatic Brain Injury: Evaluation of CONSORT Item Adherence

Traumatic brain injury (TBI) contributes to death and disability, resulting in an enormous individual and socio-economic challenges. Despite huge efforts, there are still controversies on treatment strategies and early outcome estimation. We evaluate current randomized controlled trials (RCTs) on TBI according to their fulfillment of the CONSORT (Consolidated Statement of Reporting Trials) statement’s criteria as a marker of transparency and the quality of study planning and realization. A PubMed search for RCTs on TBI (January 2014–December 2019) was carried out. After screening of the abstracts (n = 1.926), the suitable full text manuscripts (n = 72) were assessed for the fulfillment of the CONSORT criteria. The mean ratio of consort statement fulfillment was 59% (±13%), 31% of the included studies (n = 22) complied with less than 50% of the CONSORT criteria. Citation frequency was moderately related to ratio of CONSORT item fulfillment (r = 0.4877; p < 0.0001) and citation frequency per year (r = 0.5249; p < 0.0001). The ratio of CONSORT criteria fulfillment was associated with the impact factor of the publishing journal (r = 0.6428; p < 0.0001). Essential data for study interpretation, such as sample size determination (item 7a), participant flow (item 13a) as well as losses and exclusions (item 13b), were only reported in 53%, 60% and 63%, respectively. Reporting and methodological aspects in RCTs on TBI still may be improved. Thus, the interpretation of study results may be hampered due to methodological weaknesses.

Effective use of weight-based enoxaparin for deep vein thrombosis chemoprophylaxis in patients with traumatic brain injury

BACKGROUND

Enoxaparin is the recommended agent for deep vein thrombosis (DVT) chemoprophylaxis in trauma patients. Current literature suggests weight-based dosing is superior to standard dosing for adequate chemoprophylaxis. Literature regarding the use of weight-based enoxaparin in the setting of traumatic brain injury (TBI) however is limited.

METHODS

A retrospective analysis of adult trauma patients admitted between January 1, 2018 to February 28, 2019 was performed. Sixty-six patients with TBI receiving weight-based enoxaparin met inclusion criteria. Incidence of intracranial hemorrhage (ICH) expansion was the primary endpoint. Newly diagnosed venous thromboembolism (VTE) and death were secondary endpoints.

RESULTS

Two patients, out of sixty-six, had progression of their TBI requiring surgical intervention. Newly diagnosed VTE occurred in one patient. No deaths were due to ICH expansion or VTE.

CONCLUSIONS

Use of weight-based enoxaparin dosing in the setting of TBI shows promise without an increased incidence of ICH expansion when compared to other studies. Level of Evidence and Study Type: Level IV, Therapeutic.

Enoxaparin Attenuates Acute Lung Injury and Inflammasome Activation after Traumatic Brain Injury

Traumatic brain injury (TBI) patients frequently develop cardiopulmonary system complications such as acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). However, the mechanism by which TBI causes ALI/ARDS is not fully understood. Here, we used a severe TBI model to examine the effects of a low-molecular-weight heparin, enoxaparin, on inflammasome activation and lung injury damage. We investigated whether enoxaparin inhibits ALI and inflammasome signaling protein expression in the brain and lungs after TBI in mice. C57/BL6 mice were subjected to severe TBI and were treated with vehicle or 1 mg/kg of enoxaparin 30 min after injury. Lung and brain tissue were collected 24 h post-TBI and were analyzed by immunoblotting for expression of the inflammasome proteins, caspase-1 and interleukin (IL)-1β. In addition, lung tissue was collected for histological analysis to determine ALI scoring and neutrophil and macrophage infiltration post-injury. Our data show that severe TBI induces increased expression of inflammasome proteins caspase-1 and IL-1β in the brain and lungs of mice after injury. Treatment with enoxaparin attenuated inflammasome expression in the brain and lungs 24 h after injury. Enoxaparin significantly decreased ALI score as well as neutrophil and macrophage infiltration in lungs at 24 h after injury. This study demonstrates that enoxaparin attenuates ALI and inhibits inflammasome expression in the brain and lungs after TBI. These findings support the hypothesis that inhibition of the neural-respiratory inflammasome axis that is activated after TBI may have therapeutic potential.

The Safety of Early Thromboembolic Prophylaxis in Closed Traumatic Intracranial Hemorrhage

Background

Venous thromboembolism (VTE) is a major cause of morbidity and mortality in patients with traumatic brain injury (TBI); this study is testing the safety of enoxaparin use for the prevention of venous thromboembolism in this group of patients.

Patients and Methods

From January 2016 to May 2018, 46 patients (36 males, 10 females) with closed traumatic intracranial bleeding received early (ie, within 72 hours) venous thromboembolic prophylaxis with 40 mg of enoxaparin. Patients with traumatic intracranial hemorrhage were followed up both clinically and with repeated brain computed tomography to examine the safety of enoxaparin VTE prophylaxis.

Results

The age of the patients ranged from 16–91 years (43.9±25.8 years). Glasgow coma score ranged from 5–15 (9.9±4.7). Twenty patients had mild TBI (GCS 15–13), 17 patients had moderate TBI (GCS 12–9), and nine patients had severe TBI (GCS≤8). Brain computed tomography showed variable types of brain injuries. Non-surgical management was applied for 18 patients. Craniotomy and surgical evacuation of significant (≥1cm in maximum diameter) EDH and/or SDH was carried out in 26 patients. External ventricular drain was inserted in two patients with significant IVH. Thirty-eight patients had good overall outcome, eight patients showed poor outcome. None of the reviewed patients developed clinical deterioration and/or progression of the intracranial bleeding on follow-up brain CT scans.

Conclusion

Enoxaparin is a safe prophylaxis against venous thromboembolism in patients with traumatic closed intracranial bleeding.

Multi-target approaches to CNS repair: olfactory mucosa-derived cells and heparan sulfates

Spinal cord injury (SCI) remains one of the biggest challenges in the development of neuroregenerative therapeutics. Cell transplantation is one of numerous experimental strategies that have been identified and tested for efficacy at both preclinical and clinical levels in recent years. In this Review, we briefly discuss the state of human olfactory cell transplantation as a therapy, considering both its current clinical status and its limitations. Furthermore, we introduce a mesenchymal stromal cell derived from human olfactory tissue, which has the potential to induce multifaceted reparative effects in the environment within and surrounding the lesion. We argue that no single therapy will be sufficient to treat SCI effectively and that a combination of cell-based, rehabilitation and pharmaceutical interventions is the most promising approach to aid repair. For this reason, we also introduce a novel pharmaceutical strategy based on modifying the activity of heparan sulfate, an important regulator of a wide range of biological cell functions. The multi-target approach that is exemplified by these types of strategies will probably be necessary to optimize SCI treatment.