Safety and efficacy of early thromboembolism chemoprophylaxis after intracranial hemorrhage from traumatic brain injury

A collaborative multidisciplinary trauma program improvement team improves VTE chemoprophylaxis guideline compliance in non-operative stable TBI

BACKGROUND

Delays in initiating venous thromboembolism (VTE) prophylaxis in patients suffering from traumatic brain injury (TBI) persist despite guidelines recommending early initiation. We hypothesized that the expansion of a Trauma Program Performance Improvement (PI) team will improve compliance of early (24-48 hours) initiation of VTE prophylaxis and will decrease VTE events in TBI patients.

METHODS

We performed a single-center retrospective review of all TBI patients admitted to a Level I trauma center before (2015-2016,) and after (2019-2020,) the expansion of the Trauma Performance Improvement and Patient Safety (PIPS) team and the creation of trauma process and outcome dashboards. Exclusion criteria included discharge or death within 48 hours of admission, expanding intracranial hemorrhage on CT scan, and a neurosurgical intervention (craniotomy, pressure monitor, or drains) prior to chemoprophylaxis initiation.

RESULTS

A total of 1,112 patients met the inclusion criteria, of which 54% (n = 604) were admitted after Trauma PIPS expansion. Following the addition of a dedicated PIPS nurse in the trauma program and creation of process dashboards, the time from stable CT to VTE prophylaxis initiation decreased (52 hours to 35 hours; p < 0.001) and more patients received chemoprophylaxis at 24 hours to 48 hours (59% from 36%, p < 0.001) after stable head CT. There was no significant difference in time from first head CT to stable CT (9 vs. 9 hours; p = 0.15). The Contemporary group had a lower rate of VTE events (1% vs. 4%; p < 0.001) with no increase in bleeding events (2% vs. 2%; p = 0.97). On multivariable analysis, being in the Early cohort was an independent predictor of VTE events (adjusted odds ratio, 3.74; 95% confidence interval, 1.45-6.16).

CONCLUSION

A collaborative multidisciplinary Trauma PIPS team improves guideline compliance. Initiation of VTE chemoprophylaxis within 24 hours to 48 hours of stable head CT is safe and effective.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level IV.

Early administration of high dose enoxaparin after traumatic brain injury

BACKGROUND

Early enoxaparin 30 mg BID administration at 24 h post-injury has been demonstrated in patients with traumatic brain injury (TBI). However this dose can also yield subtherapeutic anti-Xa levels in 30-50% of trauma patients, suggesting that larger doses may be required for adequate prophylaxis against venous thromboembolism (VTE). The safety of enoxaparin 40 mg BID in trauma patients has previously been shown - however, these studies have largely excluded TBI patients. Therefore, we sought to demonstrate the safety of early enoxaparin 40 mg BID in a low-risk group of TBI patients.

METHODS

A retrospective review of TBI patients at a Level 1 trauma center was performed. Patients with stable computed tomography (CT) of the head at 6 to 24 h post-injury who received enoxaparin 40 mg BID were included and serial GCS evaluations to identify possible clinical complications. To evaluate the safety of this dosing regimen, data was then compared to patients from our institution with similar TBI profiles who had received 5,000 units (U) of subcutaneous heparin (SQH) prophylaxis.

RESULTS

199 TBI patients were identified over a nine month period, 40/199 (19.7%) received DVT prophylaxis after traumatic injury. Of these 40, 19 (47.5%) received enoxaparin 40 mg BID and 21 (52.5%) received 5,000U of SQH. Low risk TBI patients who were either given enoxaparin (n = 7) or SQH (n = 4), demonstrated no clinical decline in mental status during their inpatient stay.

CONCLUSION

Prior studies have demonstrated that enoxaparin 40 mg BID dosing is superior to traditional VTE prophylaxis in trauma patients. However, TBI patients are often excluded from this dosing due to concern for progression. Our study showed no clinical decline in mental status in a small cohort of low-risk TBI patients who received enoxaparin 40 mg BID.

A majority of trauma-related deep venous thromboses resolve prior to discharge

Post-traumatic DVTs present unique challenges in patient populations with specific high-risk injury patterns. Duplex ultrasound (US) can be used to assess evolution of DVTs and may guide treatment for high-risk patients. We hypothesized that many DVTs resolve during the initial admission. Weekly duplex US are ordered on all trauma inpatients regardless of prior DVT at our facility. We reviewed US and outcomes data on all patients with lower extremity DVTs at our Level I trauma center from January 2012-December 2021. 392 patients were diagnosed with lower extremity DVT by US. 261 (67%) patients received follow-up US with a mean time to repeat US of 6 days. Of these, 91 (35%) patients experienced DVT resolution prior to the first follow-up US, and 141 (54%) patients experienced resolution prior to discharge. Mean time to resolution was 10 days. Over 50% of DVTs resolve before discharge and are detected by US. Further studies and post-discharge follow-up are needed to determine if patients with resolved DVTs can be managed without therapeutic anticoagulation.

Timing of venous thromboembolism prophylaxis initiation after injury: Findings from the consensus conference to implement optimal VTE prophylaxis in trauma

ABSTRACT

Optimizing prophylaxis against venous thromboembolic events (VTEs) is a critical issue in the care of injured patients. Although these patients are at significant risk of developing VTE, they also present competing concerns related to exacerbation of bleeding from existing injuries. Especially after high-risk trauma, including injuries to the abdominal solid organs, brain, and spine, trauma providers must delineate the time period in which VTE prophylaxis successfully reduces VTE rates without encouraging bleeding. Although existing data are primarily retrospective in nature and further study is required, literature supports early VTE chemoprophylaxis initiation even for severely injured patients. Early initiation is most frequently defined as <48 hours from admission but varies from <24 hours to 72 hours and occasionally refers to time from initial trauma. Prior to chemical VTE prophylaxis initiation in patients at risk for bleeding, an observation period is necessary during which injuries must show themselves to be hemostatic, either clinically or radiographically. In the future, prospective examination of optimal timing of VTE prophylaxis is necessary. Further study of specific subsets of trauma patients will allow for development of effective VTE mitigation strategies based upon collective risks of VTE and hemorrhage progression.

Indian Society of Critical Care Medicine Consensus Statement for Prevention of Venous Thromboembolism in the Critical Care Unit

Deep vein thrombosis (DVT) is a preventable complication of critical illness, and this guideline aims to convey a pragmatic approach to the problem. Guidelines have multiplied over the last decade, and their utility has become increasingly conflicted as the reader interprets all suggestions or recommendations as something that must be followed. The nuances of grade of recommendation vs level of evidence are often ignored, and the difference between a "we suggest" vs a "we recommend" is overlooked. There is a general unease among clinicians that failure to follow the guidelines translates to poor medical practice and legal culpability. We attempt to overcome these limitations by highlighting ambiguity when it occurs and refraining from dogmatic recommendations in the absence of robust evidence. Readers and practitioners may find the lack of specific recommendations unsatisfactory, but we believe that true ambiguity is better than inaccurate certainty. We have attempted to comply with the guidelines on how to create guidelines.1 And to overcome the poor compliance with these guidelines.2 Some observers have expressed concern that DVT prophylaxis guidelines may cause more harm than good.3 We have placed greater emphasis on large randomized controlled trials (RCTs) with clinical end point and de-emphasized RCTs with surrogate end points and also de-emphasized hypothesis generating studies (observational studies, small RCTs, and meta-analysis of these studies). We have de-emphasized RCTs in non-intensive care unit populations like postoperative patients or those with cancer and stroke. We have also considered resource limitation settings and have avoided recommending costly and poorly proven therapeutic options.

How to cite this article

Jagiasi BG, Chhallani AA, Dixit SB, Kumar R, Pandit RA, Govil D, et al. Indian Society of Critical Care Medicine Consensus Statement for Prevention of Venous Thromboembolism in the Critical Care Unit. Indian J Crit Care Med 2022;26(S2):S51-S65.

Early bilateral pulmonary embolism in a polytrauma patient: About a case report

Introduction

and importance: Venous thromboembolism (VTE) is a well-known complication in polytrauma patients, associated with a high rate of mortality and morbidity. Generally pulmonary embolism (PE) is most common between the fifth and seventh days following a significant trauma, and it is uncommon before the fourth day. Their management remains a challenge to physicians given the nature and risk of blood loss from the accompanying injuries must be considered while using anticoagulant therapy.

Case presentation

Here we present a case of acute pulmonary embolism in a previously healthy young woman that developed two days after a traumatic brain injury (TBI) and varying degrees of additional blunt thoracic trauma. An angio CT scan was used to make the diagnosis, and the patient was given anticoagulant medication with close monitoring and satisfactory outcomes.

Conclusion

Evidence suggests that early after trauma, a considerable number of trauma patients are hypercoagulable. In patients with unexplained dyspnea/hypoxia, clinicians should maintain a high index of suspicion and explore PE early after injury. In the case of traumatic brain injury patients with cerebral contusions, intraparenchymal haemorrhages, or subdural/extradural haemorrhages, the existence of post-traumatic PE adds to the problems.

•

Our aim was to investigate the (PE) in polytrauma patients: incidence, risk factors of early occurrence, management and outcomes.

•

Decision to anti-coagulate post traumatic PE is controversial, especially in polytrauma patients.

•

Anticoagulation decision is guided by interval repeat CT scan and clinical picture.

•

The presence of post traumatic PE poses further challenges in the management of traumatic brain injury patients with cerebral contusions, intraparenchymal haemorrhages or subdural/extradural haemorrhages.

Clinical Significance of Vascular Occlusive Events following Moderate-to-Severe Traumatic Brain Injury: An Observational Cohort Study

Preventing hemorrhage progression is a potential therapeutic opportunity in traumatic brain injury (TBI) management, but its use has been limited by fear of provoking vascular occlusive events (VOEs). However, it is currently unclear whether VOE actually affects outcome in these patients. The aim of this study was to determine incidence, risk factors, and clinical significance of VOE in patients with moderate-to-severe TBI. A retrospective observational cohort study of adults (≥15 years) with moderate-to-severe TBI was performed. The presence of a VOE during hospitalization was noted from hospital charts and radiological reports. Functional outcome, using the Glasgow Outcome Scale (GOS), was assessed at 12 months posttrauma. Univariate and multivariate logistic regressions were used for endpoint assessment. In total, 848 patients were included, with a median admission Glasgow Coma Scale of 7. A VOE was detected in 54 (6.4%) patients, of which cerebral venous thrombosis was the most common (3.2%), followed by pulmonary embolism (1.7%) and deep vein thrombosis (1.3%). Length of ICU stay (p < 0.001), body weight (p = 0.002), and skull fracture (p = 0.004) were independent predictors of VOE. VOE development did not significantly impact 12-month GOS, even after adjusting for potential confounders using propensity score matching. In conclusion, VOE in moderate-to-severe TBI patients was relatively uncommon, and did not affect 12-month GOS. This suggests that the potential benefit of treating bleeding progression might outweigh the risks of VOE.

The association of timing of pharmacological prophylaxis and venous thromboembolism in patients with moderate-to-severe traumatic brain injury: A retrospective cohort study

OBJECTIVES:

Patients with traumatic brain injury (TBI) have an increased risk for venous thromboembolism (VTE). The current guidelines recommend pharmacologic prophylaxis, but its timing remains unclear.

METHODS:

In this retrospective cohort study, patients with moderate-to-severe TBI admitted to a tertiary care intensive care unit between 2016 and 2019 were categorized into two groups according to the timing of pharmacologic prophylaxis: early if prophylaxis was given within 72 h from hospital admission and late if after 72 h.

RESULTS:

Of the 322 patients in the cohort, 46 (14.3%) did not receive pharmacological prophylaxis, mainly due to early brain death; 152 (47.2%) received early pharmacologic prophylaxis and 124 (38.5%) received late prophylaxis. Predictors of late pharmacologic prophylaxis were lower body mass index, intracerebral hemorrhage (odds ratio [OR], 3.361; 95% confidence interval [CI], 1.269–8.904), hemorrhagic contusion (OR, 3.469; 95% CI, 1.039–11.576), and lower platelet count. VTE was diagnosed in 43 patients on a median of 10 days after trauma (Q1, Q3: 5, 15): 6.6% of the early prophylaxis group and 26.6% of the late group (P < 0.001). On multivariable logistic regression analysis, the predictors of VTE were Acute Physiology and Chronic Health Evaluation II score, subarachnoid hemorrhage, and late versus early pharmacologic prophylaxis (OR, 3.858; 95% CI, 1.687–8.825). The late prophylaxis group had higher rate of tracheostomy, longer duration of mechanical ventilation and stay in the hospital, lower discharge Glasgow coma scale, but similar survival, compared with the early group.

CONCLUSIONS:

Late prophylaxis (>72 h) was associated with higher VTE rate in patients with moderate-to-severe TBI, but not with higher mortality.

Time is of the Essence: Impact of a More Aggressive Chemical Venous Thromboembolism Prophylaxis Regimen on Trauma Patients

BACKGROUND

Trauma patients are at high risk for venous thromboembolism (VTE). Opportunity for chemical VTE prophylaxis improvement was identified and practice was altered to start chemoprophylaxis on admission in most patients. The purpose of this study was to determine if early VTE prophylaxis is safe and reduces VTE.

METHODS

The trauma registry was queried over a 12-month period for patients admitted greater than 1 day for traumatic injury. The study spanned 6 months on either side of instituting aggressive chemoprophylaxis. Patients were risk adjusted on demographics, Injury Severity Score, transfusions, procedure type, length of stay, and mortality. Pre-intervention patients were then compared to patients in the aggressive cohort with the primary outcome of VTE. Secondary outcomes included transfusions, mortality, and length of stay (LOS).

RESULTS

1597 patients were identified over the study period with 754 (47%) patients in the aggressive period. There were no differences in age, sex, Injury Severity Score, transfusions, procedures, or LOS between cohorts. Pre-algorithm patients were more likely to have penetrating mechanism (9.3% vs 6.6%; P = .009) and longer time to VTE prophylaxis (23.3 vs 13.9 hours; P < .001). No differences were noted in anticoagulant, VTE rate (2.0% vs 1.2%; P = .195), or mortality. Linear regression analysis identified time to chemical prophylaxis as significant predictor of VTE (β = 43.9, P < .001).

CONCLUSIONS

Early aggressive chemical VTE prophylaxis is safe without increasing transfusions. Venous thromboembolism rates were decreased, but did not reach statistical significance.

Characterizing the delays in adequate thromboprophylaxis after TBI

Background

We sought to compare enoxaparin dosing for venous thromboembolism (VTE) prophylaxis in trauma patients with and without traumatic brain injury (TBI) to better understand the time and dose required to reach target anti-Xa levels. Our hypothesis was that patients with TBI have significant delays in the initiation of adequate pharmacological prophylaxis and require a higher enoxaparin dose than currently recommended.

Methods

The medical records of trauma patients who received enoxaparin dosing based on anti-Xa trough levels between August 2014 and October 2016 were reviewed. Patients were included if their anti-Xa trough level reached the target range (0.1 IU/mL to 0.2 IU/mL).

Results

A total of 163 patients had anti-Xa levels within the target range of which 41 (25.2%) had TBI. Patients with TBI had longer delays before initiating enoxaparin (7.5 days vs. 1.5 days after admission, p<0.01) and were more likely to receive unfractionated heparin prior to enoxaparin (46.3% vs. 11.5%, p<0.01). Anti-Xa levels reached the target range later in patients with TBI (11 days vs. 5 days after admission, p<0.01). Enoxaparin 40 mg two times per day was the median dose required to reach the target anti-Xa levels for both cohorts. VTE rates were higher among patients with TBI (22.0% vs. 9.0%, p=0.03). Four patients (9.8%) had progression of their intracranial hemorrhage prior to receiving enoxaparin, although none progressed during enoxaparin administration.

Conclusion

Among patients with TBI who reached target anti-Xa levels, 11 days after admission were required to reach a median enoxaparin dose of 40 mg two times per day. Unfractionated heparin was used as pharmacological prophylaxis in about half of these patients. The delay in reaching the target anti-Xa levels and the use of unfractionated heparin likely contribute to the higher VTE rate in patients with TBI.

Level of evidence

Level III, therapeutic.

How do you manage ANTICOagulant therapy in neurosurgery? The ANTICO survey of the Italian Society of Neurosurgery (SINCH)

BACKGROUND

Anticoagulant assumption is a concern in neurosurgical patient that implies a delicate balance between the risk of thromboembolism versus the risk of peri- and postoperative hemorrhage.

METHODS

We performed a survey among 129 different neurosurgical departments in Italy to evaluate practice patterns regarding the management of neurosurgical patients taking anticoagulant drugs. Furthermore, we reviewed the available literature, with the aim of providing a comprehensive but practical summary of current recommendations.

RESULTS

Our survey revealed that there is a lack of knowledge, mostly regarding the indication and the strategies of anticoagulant reversal in neurosurgical clinical practice. This may be due a lack of national and international guidelines for the care of anticoagulated neurosurgical patients, along with the fact that coagulation and hemostasis are not simple topics for a neurosurgeon.

CONCLUSIONS

To overcome this issue, establishment of hospital-wide policy concerning management of anticoagulated patients and developed in an interdisciplinary manner are strongly recommended.

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.

“Death Knell” for Prophylactic Vena Cava Filters? A 20-Year Experience with a Venous Thromboembolism Guideline

The role of prophylactic vena cava filters (pVCFs) in trauma patients remains controversial. After 20 years of data collection and experience, we reviewed our venous thromboembolism guideline for the efficacy of pVCFs in preventing pulmonary embolism (PE). A retrospective cohort study was performed using our Level I trauma center registry from January 1997 thru December 2016. This population was then divided by the presence of pVCFs. Univariate analysis was performed comparing the incidence of PEs, deep vein thrombosis, and mortality between those with and without a pVCF. There were 35,658 patients identified, of whom 2 per cent (n = 847) received pVCFs. The PE rate was 0.4 per cent in both groups. The deep vein thrombosis rate for pVCFs was 3.9 per cent compared with 0.6 per cent in the no-VCF group ( P < 0.0001). Given that there was no difference in the rates of PEs between the cohorts, the subset of patients with a PE were analyzed by their risk factors. Only ventilator days > 3 were associated with a higher risk in the no-pVCF group (0.2 vs 1.5%, P = 0.033). pVCFs did not confer benefit reducing PE rate. In addition, despite their intended purpose, pVCFs cannot eliminate PEs in high-risk trauma patients, suggesting a lack of utility for prophylaxis in this population.

Retrievable inferior vena cava filters in neurosurgical patients: Retrieval rates and clinical outcomes

OBJECTIVE

To assess inferior vena cava (IVC) filter retrieval rates and clinical outcomes in neurosurgical patients and to determine patient characteristics associated with filter retrieval.

PATIENTS AND METHODS

This single-center retrospective study included 204 consecutive neurosurgical patients (120 men, 84 women; mean age 60 ± 13 years) who underwent retrievable IVC filter insertion between 1/2011-9/2013. Institutional IVC filter database review was used to identify demographic and clinical data, indication for IVC filtration, and IVC filter type. Patients were followed clinically by the neurosurgical, hematology, and interventional radiology services until removal or conversion to a permanent device. Measured outcomes included filter retrieval rates and parameters associated with device removal.

RESULTS

The majority of filters were placed for venous thromboembolism (200/204, 98%). Of 204 filters, 38(19%) were retrieved at median 186 days post-placement (range 3-665 days), 112(55%) converted to permanent devices, 44(22%) patients were deceased, and 10(5%) patients were lost to follow-up after transfer to an outside healthcare facility. Patients with subarachnoid hemorrhage (18% vs. 35%, p = 0.025) and malignancy (5% vs. 25%, p = 0.009) were less likely to have filters removed. Filter type (p = 0.475), gender (p = 0.221), neurosurgical procedure (p = 0.639), and insurance status (p = 0.207) did not demonstrate a significant association with filter retrieval.

CONCLUSION

IVC filter retrieval rates in neurosurgical patients are low despite tracking patients clinically in a multidisciplinary setting. Those neurosurgical patients with intracranial hemorrhage or malignancy requiring IVC filters have a lower likelihood of filter retrieval and may benefit from use of permanent devices.

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

Background:

Enoxaparin was shown to have a neuroprotective effect in animal models as well as a human study following traumatic brain injury. This study was conducted to assess the effect of enoxaparin on the clinical outcome of severe traumatic brain injury (TBI) and its safety.

Methods:

This study is a randomized double-blinded placebo-controlled trial. The inclusion criteria were age 16–70, a closed head injury, a postresuscitation Glasgow Coma Scale (GCS) between 5 and 8, and a latency time between the injury and entering the study of less than 5 h. The patients were randomized into enoxaparin and placebo groups. In the enoxaparin group, 0.5 mg/kg enoxaparin was injected subcutaneously every 6 h in six total doses. The two groups were compared for the occurrence of intracranial hematoma (ICH) and for clinical neurological outcome, assessed by the Glasgow Outcome Scale.

Results:

Twenty-seven patients were assigned to the placebo group and 26 to the enoxaparin group. The two groups were similar regarding baseline characteristics, including age, sex, postresuscitation GCS, and best motor response. The occurrence of new ICH or an ICH size increase was insignificantly more frequent in the enoxaparin group than the placebo group (26.9% vs. 7.4%, P = 0.076). The favorable outcome rate in the enoxaparin group was significantly higher than in the placebo group (57.7% vs. 25.9%, P = 0.019).

Conclusions:

This study showed that the early administration of enoxaparin could lead to favorable outcomes in severe TBI patients without significantly increasing cerebral hemorrhagic complications.

Early Venous Thromboembolism Chemoprophylaxis After Traumatic Intracranial Hemorrhage

BACKGROUND

Venous thromboembolism is a common complication of traumatic brain injury with an estimated incidence of 25% when chemoprophylaxis is delayed. The timing of initiating prophylaxis is controversial given the concern for hemorrhage expansion.

OBJECTIVE

To determine the safety of initiating venous thromboembolic event (VTE) chemoprophylaxis within 24 h of presentation.

METHODS

We performed a retrospective analysis of patients with traumatic intracranial hemorrhage presenting to a level I trauma center. Patients receiving early chemoprophylaxis (<24 h) were compared to the matched cohort of patients who received heparin in a delayed fashion (>48 h). The primary outcome of the study was radiographic expansion of the intracranial hemorrhage. Secondary outcomes included VTE, use of intracranial pressure (ICP) monitoring, delayed decompressive surgery, and all-cause mortality.

RESULTS

Of 282 patients, 94 (33%) received chemoprophylaxis within 24 h of admission. The cohorts were evenly matched across all variables. The primary outcome occurred in 18% of patients in the early cohort compared to 17% in the delayed cohort (P = .83). Fifteen patients (16%) in the early cohort underwent an invasive procedure in a delayed fashion; this compares to 35 patients (19%) in the delayed cohort (P = .38). Five patients (1.7%) in our study had a VTE during their hospitalization; 2 of these patients received early chemoprophylaxis (P = .75). The rate of mortality from all causes was similar in both groups.

CONCLUSION

Early (<24 h) initiation of VTE chemoprophylaxis in patients with traumatic intracranial hemorrhage appears to be safe. Further prospective studies are needed to validate this finding.

A Systematic Review of the Risks and Benefits of Venous Thromboembolism Prophylaxis in Traumatic Brain Injury

BACKGROUND

Patients suffering from traumatic brain injury (TBI) are at increased risk of venous thromboembolism (VTE). However, initiation of pharmacological venous thromboprophylaxis (VTEp) may cause further intracranial hemorrhage. We reviewed the literature to determine the postinjury time interval at which VTEp can be administered without risk of TBI evolution and hematoma expansion.

METHODS

MEDLINE and EMBASE databases were searched. Inclusion criteria were studies investigating timing and safety of VTEp in TBI patients not previously on oral anticoagulation. Two investigators extracted data and graded the papers' levels of evidence. Randomized controlled trials were assessed for bias according to the Cochrane Collaboration Tool and Cohort studies were evaluated for bias using the Newcastle-Ottawa Scale. We performed univariate meta-regression analysis in an attempt to identify a relationship between VTEp timing and hemorrhagic progression and assess study heterogeneity using an I 2 statistic.

RESULTS

Twenty-one studies were included in the systematic review. Eighteen total studies demonstrated that VTEp postinjury in patients with stable head computed tomography scan does not lead to TBI progression. Fourteen studies demonstrated that VTEp administration 24 to 72 hours postinjury is safe in patients with stable injury. Four studies suggested that administering VTEp within 24 hours of injury in patients with stable TBI does not lead to progressive intracranial hemorrhage. Overall, meta-regression analysis demonstrated that there was no relationship between rate of hemorrhagic progression and VTEp timing.

CONCLUSIONS

Literature suggests that administering VTEp 24 to 48 hours postinjury may be safe for patients with low-hemorrhagic-risk TBIs and stable injury on repeat imaging.

Contemporary thromboprophylaxis of trauma patients

PURPOSE OF REVIEW

The traumatically injured patient is at high risk for developing venous thromboembolism. Clinical practice guidelines developed by the American College of Chest Physicians and the Eastern Association for the Surgery of Trauma recognize the importance of initiating thromboprophylaxis, but the guidelines lack specific recommendations regarding the timing and dose of pharmacologic thromboprophylaxis. We review the literature regarding initiation of thromboprophylaxis in different injuries, the use of inferior vena cava filters, laboratory monitoring, dosing regimens, and the use of antiplatelet therapy.

RECENT FINDINGS

Use of pharmacologic thromboprophylaxis with invasive intracranial monitors is not associated with increased bleeding complications. The initiation of low-molecular-weight heparin (LMWH) prophylaxis 48 h postinjury in blunt solid organ injury is not associated with an increase in the rate of failed nonoperative management. Antiplatelet therapy in conjunction with LMWH may help to prevent venous thromboembolism.

SUMMARY

In the setting of blunt traumatic brain and solid organ injury, initiation of pharmacologic thromboprophylaxis 48 h after injury is not associated with increased bleeding complications. There is no consensus or clear data showing which dosing regimen of LMWH is most effective or whether routine laboratory measurements are beneficial for determining effective thromboprophylaxis.

Anticoagulation therapy in atrial fibrillation after intracranial hemorrhage

BACKGROUND

The effect of oral anticoagulation therapy (OAT) in patients with atrial fibrillation (AF) with a history of intracranial hemorrhage (ICH) is poorly defined.

OBJECTIVE

The purpose of this study was to evaluate the efficacy and safety of OAT in patients with AF with an ICH history.

METHODS

We retrospectively compared the composite end point, including thromboembolic and major bleeding events, between patients with AF with a history of ICH who were (OAT group, n = 254) and those who were not (no-OAT group, n = 174) taking OAT.

RESULTS

During a mean follow-up of 39.5 ± 31.9 months, 5.5 and 3.1 major bleeding events/100 patient-years were observed in the OAT and no-OAT groups, respectively (P = .024). Recurrent ICH was observed only in patient with OAT. Thromboembolic events occurred in 2.4 and 8.3 events/100 patient-years in OAT and no-OAT groups, respectively (P < .001). There was no significant differences in composite end points between OAT and no-OAT groups (11.5 events/100 patient-years vs 7.9 events/100 patient-years; P = .154). Patients with OAT who achieved a time-in-therapeutic range of ≥60% of the international normalized ratio of 2.0-3.0 demonstrated a better cumulative survival free of the composite end point (P < .001) than did patients without OAT. Early (<2 weeks) OAT after an index ICH did not improve composite end points because of the increased incidence of major bleeding events. However, OAT at 2 weeks after an index ICH was associated with decreased clinical events including thromboembolic events and composite end point.

CONCLUSION

In patients with AF who require anticoagulation and have a history of ICH, maintaining optimal OAT with time-in-therapeutic range ≥ 60% and the initiation of OAT at least 2 weeks after an index ICH were associated with improved clinical outcomes.

Management of Traumatic Brain Injury

Traumatic brain injury remains a serious public health problem, causing death and disability for millions. In order to maximize outcomes in the face of a complex injury to a complex organ, a variety of advanced neuromonitoring techniques may be used to guide surgical and medical decision-making. Because of the heterogeneity of injury types and the plethora of treatment confounders present in this patient population, the scientific study of specific interventions is challenging. This challenge highlights the need for a firm understanding of the anatomy and pathophysiology of brain injuries when making clinical decisions in the intensive care unit.

Dual-Energy CT in Enhancing Subdural Effusions that Masquerade as Subdural Hematomas: Diagnosis with Virtual High-Monochromatic (190-keV) Images

BACKGROUND AND PURPOSE

Extravasation of iodinated contrast into subdural space following contrast-enhanced radiographic studies results in hyperdense subdural effusions, which can be mistaken as acute subdural hematomas on follow-up noncontrast head CTs. Our aim was to identify the factors associated with contrast-enhancing subdural effusion, characterize diffusion and washout kinetics of iodine in enhancing subdural effusion, and assess the utility of dual-energy CT in differentiating enhancing subdural effusion from subdural hematoma.

MATERIALS AND METHODS

We retrospectively analyzed follow-up head dual-energy CT studies in 423 patients with polytrauma who had undergone contrast-enhanced whole-body CT. Twenty-four patients with enhancing subdural effusion composed the study group, and 24 randomly selected patients with subdural hematoma were enrolled in the comparison group. Postprocessing with syngo.via was performed to determine the diffusion and washout kinetics of iodine. The sensitivity and specificity of dual-energy CT for the diagnosis of enhancing subdural effusion were determined with 120-kV, virtual monochromatic energy (190-keV) and virtual noncontrast images.

RESULTS

Patients with enhancing subdural effusion were significantly older (mean, 69 years; 95% CI, 60-78 years; P < .001) and had a higher incidence of intracranial hemorrhage (P = .001). Peak iodine concentration in enhancing subdural effusions was reached within the first 8 hours of contrast administration with a mean of 0.98 mg/mL (95% CI, 0.81-1.13 mg/mL), and complete washout was achieved at 38 hours. For the presence of a hyperdense subdural collection on 120-kV images with a loss of hyperattenuation on 190-keV and virtual noncontrast images, when considered as a true-positive for enhancing subdural effusion, the sensitivity was 100% (95% CI, 85.75%-100%) and the specificity was 91.67% (95% CI, 73%-99%).

CONCLUSIONS

Dual-energy CT has a high sensitivity and specificity in differentiating enhancing subdural effusion from subdural hematoma. Hence, dual-energy CT has a potential to obviate follow-up studies.

Early heparin administration after traumatic brain injury: Prolonged cognitive recovery associated with reduced cerebral edema and neutrophil sequestration

BACKGROUND

Early administration of unfractionated heparin (UFH) after traumatic brain injury (TBI) reduces early in vivo circulating leukocytes (LEUs) in peri-injury penumbral brain tissue, enhancing cognitive recovery 2 days after injury. It remains unclear how long this effect lasts and if this is related to persistently accumulating LEUs in penumbral brain tissue. We hypothesized that UFH reduces LEU brain tissue sequestration resulting in prolonged cognitive recovery.

METHODS

CD1 male mice underwent either TBI by controlled cortical impact (CCI) or sham craniotomy. Unfractionated heparin (75 or 225 U/kg) or vehicle was repeatedly administered after TBI. Neurologic function (Garcia Neurological Test [maximum score = 18]) and body weight loss ratios were evaluated at 24 hours to 96 hours after TBI. Brain and lung wet-to-dry ratios, hemoglobin levels, and brain LEU sequestration (Ly6G immunohistochemistry) were evaluated 96 hours postmortem. Analysis of variance with Bonferroni correction determined significance (p < 0.05).

RESULTS

Compared with untreated CCI animals (24 hours, 14.7 ± 1.0; 48 hours, 15.5 ± 0.7; 72 hours, 15.0 ± 0.8; 96 hours, 16.5 ± 0.9), UFH75 (24 hours, 16.0 ± 1.0, p < 0.01; 48 hours, 16.5 ± 0.7, p < 0.05; 72 hours, 17.1 ± 0.6, p < 0.01; 96 hours, 17.4 ± 0.7, p < 0.05) increased cognitive recovery throughout the entire observation period after TBI. At 48 hours, UFH225 significantly worsened body weight loss (10.2 ± 4.7%) as compared with uninjured animals (5.5 ± 2.9%, p < 0.05). Both UFH75 (60.8 ± 40.9 PMNs per high-power field [HPF], p < 0.05) and UFH225 (36.0 ± 17.6 PMNs/HPF, p < 0.01) significantly decreased brain neutrophil sequestration found in untreated CCI animals (124.2 ± 44.1 PMNs/HPF) 96 hours after TBI. Compared with untreated CCI animals (78.8 ± 0.8%), UFH75 (77.3 ± 0.6%, p = 0.04) reduced cerebral edema to uninjured levels (77.4 ± 0.6%, p = 0.04 vs. CCI). Only UFH225 (10.6 ± 1.2 g/dL) resulted in lower hemoglobin than in uninjured animals (13.0 ± 1.2 g/dL, p < 0.05).

CONCLUSIONS

Heparin after TBI reduces tissue LEU sequestration and edema in injured brain for up to 4 days. This is associated with persistent improved cognitive recovery, but only when low-dose UFH is given. Early administration of UFH following TBI may blunt LEU-related cerebral swelling and slow progression of secondary brain injury.

Risk of Deep vein thrombosis in neurosurgery: State of the art on prophylaxis protocols and best clinical practices

OBJECTIVE

To analytically discuss some protocols in Deep vein thrombosis (DVT)/pulmonary Embolism (PE) prophylaxis currently use in Neurosurgical Departments around the world.

DATA SOURCES

Analysis of the prophylaxis protocols in the English literature: An analytical and narrative review of literature concerning DVT prophylaxis protocols in Neurosurgery have been conducted by a PubMed search (back to 1978).

DATA EXTRACTION

80 abstracts were reviewed, and 74 articles were extracted.

DATA ANALYSIS

The majority of DVT seems to develop within the first week after a neurosurgical procedure, and a linear correlation between the duration of surgery and DVT occurrence has been highlighted. The incidence of DVT seems greater for cranial (7.7%) than spinal procedures (1.5%). Although intermittent pneumatic compression (IPC) devices provided adequate reduction of DVT/PE in some cranial and combined cranial/spinal series, low-dose subcutaneous unfractionated heparin (UFH) or low molecular-weight heparin (LMWH) further reduced the incidence, not always of DVT, but of PE. Nevertheless, low-dose heparin-based prophylaxis in cranial and spinal series risks minor and major postoperative haemorrhages: 2-4% in cranial series, 3.4% minor and 3.4% major haemorrhages in combined cranial/spinal series, and a 0.7% incidence of major/minor haemorrhages in spinal series.

CONCLUSION

This analysis showed that currently most of the articles are represented by case series and case reports. As long as clear guidelines will not be defined and universally applied to this diverse group of patients, any prophylaxis for DVT and PE should be tailored to the individual patient with cautious assessment of benefits versus risks.

The risk of postoperative hemorrhage and efficacy of heparin for preventing deep vein thrombosis and pulmonary embolism in adult patients undergoing neurosurgery: a systematic review and meta-analysis

The aim of this meta-analysis was to examine the risk of postoperative bleeding and efficacy of heparin for preventing deep vein thrombosis (DVT) and pulmonary embolism (PE) in adult patients undergoing neurosurgery. MEDLINE, Cochrane, and EMBASE databases were searched until October 31, 2016, for randomized controlled trials (RCTs) and non-randomized comparative studies that assessed the rates of postoperative hemorrhage, DVT, PE, and mortality in adult patients undergoing neurosurgery. Nine eligible studies (five RCTs, four retrospective studies) including 874 patients treated with either unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) and 1033 patients in control group (placebo with or without compression device) were analyzed. The overall analysis revealed that there was an increase in the risk of postoperative hemorrhage in patients who received heparin (pooled OR 1.66, 95% CI 1.01 to 2.72, p=0.046) compared with no treatment group. The risk of postoperative hemorrhage was more significant if only RCTs were included in analysis. Heparin prophylaxis was associated with a decrease in the risk of DVT (pooled OR 0.48, 95% CI 0.36 to 0.65, p<0.001) and PE (pooled OR 0.25, 95% CI 0.09 to 0.73, p=0.011) but it did not affect the rate of mortality. In conclusion, heparin increased the rate of postoperative bleeding, decreased the risk of DVT, PE and venous thromboembolic event (VTE) but it did not affect the mortality of patients undergoing neurosurgery. For the heparin prophylaxis, the trade-off between the risk of postoperative bleeding and benefit of prophylaxis against VTEs requires further investigation.

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.

Unfractionated heparin after TBI reduces in vivo cerebrovascular inflammation, brain edema and accelerates cognitive recovery

BACKGROUND

Severe traumatic brain injury (TBI) may increase the risk of venous thromboembolic complications; however, early prevention with heparinoids is often withheld for its anticoagulant effect. New evidence suggests low molecular weight heparin reduces cerebral edema and improves neurological recovery after stroke and TBI, through blunting of cerebral leukocyte (LEU) recruitment. It remains unknown if unfractionated heparin (UFH) similarly affects brain inflammation and neurological recovery post-TBI. We hypothesized that UFH after TBI reduces cerebral edema by reducing LEU-mediated inflammation and improves neurological recovery.

METHODS

CD1 male mice underwent either TBI by controlled cortical impact (CCI) or sham craniotomy. UFH (75 U/kg or 225 U/kg) or vehicle (VEH, 0.9% saline) was administered 2, 11, 20, 27, and 34 hours after TBI. At 48 hours, pial intravital microscopy through a craniotomy was used to visualize live brain LEUs interacting with endothelium and microvascular fluorescein isothiocyanate-albumin leakage. Neurologic function (Garcia Neurological Test, GNT) and body weight loss ratios were evaluated 24 and 48 hours after TBI. Cerebral and lung wet-to-dry ratios were evaluated post mortem. ANOVA with Bonferroni correction was used to determine significance (p < 0.05).

RESULTS

Compared to positive controls (CCI), both UFH doses reduced post-TBI in vivo LEU rolling on endothelium, concurrent cerebrovascular albumin leakage, and ipsilateral cerebral water content after TBI. Additionally, only low dose UFH (75 U/kg) improved GNT at both 24 and 48 hours after TBI. High dose UFH (225 U/kg) significantly increased body weight loss above sham at 48 hours. Differences in lung water content and blood pressure between groups were not significant.

CONCLUSIONS

UFH after TBI reduces LEU recruitment, microvascular permeability, and brain edema to injured brain. Lower UFH doses concurrently improve neurological recovery whereas higher UFH may worsen functional recovery. Further study is needed to determine if this is caused by increased bleeding from injured brain with higher UFH doses.

Concussions, Traumatic Brain Injury, and the Innovative Use of Omega-3s

Traumatic brain injury (TBI), with its diverse heterogeneity and prolonged secondary pathogenesis, remains a clinical challenge. Clinical studies thus far have failed to identify an effective treatment strategy when a combination of targets controlling aspects of neuroprotection, neuroinflammation, and neuroregeneration is needed. Omega-3 fatty acids (n-3FA) offer the advantage of this approach. Although further clinical trial research is needed, there is a growing body of strong preclinical evidence and clinical experience that suggests that benefits may be possible from aggressively adding substantial amounts of n-3FA to optimize the nutritional foundation of TBI, concussion, and postconcussion syndrome patients. Early and optimal doses of n-3FA, even in a prophylactic setting, have the potential to improve outcomes from this potentially devastating problem. With evidence of unsurpassed safety and tolerability, n-3FA should be considered mainstream, conventional medicine, if conventional medicine can overcome its inherent bias against nutritional, nonpharmacologic therapies.

Timing of Pharmacologic Venous Thromboembolism Prophylaxis in Severe Traumatic Brain Injury: A Propensity-Matched Cohort Study

BACKGROUND

Patients with severe traumatic brain injury (sTBI) are at high risk for developing venous thromboembolism (VTE). Nonetheless, pharmacologic VTE prophylaxis is often delayed out of concern for precipitating extension of intracranial hemorrhage (ICH). The purpose of this study was to compare the effectiveness of early vs late VTE prophylaxis in patients with sTBI, and to characterize the risk of subsequent ICH-related complication.

STUDY DESIGN

Adults with isolated sTBI (head Abbreviated Injury Scale score ≥3 and total Glasgow Coma Scale score ≤8) who received VTE prophylaxis with low-molecular-weight or unfractionated heparin were derived from the American College of Surgeons Trauma Quality Improvement Program (2012 to 2014). Patients were divided into EP (<72 hours) or LP (≥72 hours) groups. Propensity score matching was used to minimize selection bias. The primary end point was VTE (pulmonary embolism or deep vein thrombosis). Secondary outcomes were defined as late neurosurgical intervention (≥72 hours) or death.

RESULTS

We identified 3,634 patients with sTBI. Early prophylaxis was given in 43% of patients. Higher head injury severity, presence of ICH, and early neurosurgery were associated with late prophylaxis. Propensity score matching yielded a well-balanced cohort of 2,468 patients. Early prophylaxis was associated with lower rates of both pulmonary embolism (odds ratio = 0.48; 95% CI, 0.25-0.91) and deep vein thrombosis (odds ratio = 0.51; 95% CI, 0.36-0.72), but no increase in risk of late neurosurgical intervention or death.

CONCLUSIONS

In this observational study of patients with sTBI, early initiation of VTE prophylaxis was associated with decreased risk of pulmonary embolism and deep vein thrombosis, but no increase in risk of late neurosurgical intervention or death. Early prophylaxis may be safe and should be the goal for each patient in the context of appropriate risk stratification.

Venous thromboembolism prophylaxis in neurosurgical trauma patients

BACKGROUND

Venous thromboembolisms (VTEs) occur more frequently in patients with traumatic brain injuries (TBIs) and spinal cord injuries, yet the use of chemoprophylaxis is controversial. The purpose of this study was to investigate the relationship between the timing of chemical VTE prophylaxis initiation and the development of VTE events in these patients.

METHODS

Prospective data were collected and retrospectively reviewed on 1425 patients sustaining TBIs or spinal injuries from 2010 to 2014. Patients were reviewed with respect to age, gender, injury severity score, Glasgow coma score, and mechanism of injury as well as timing of initiation of chemical VTE prophylaxis and presence or absence of VTE.

RESULTS

Patients who developed a VTE had a significantly longer time to initiation of chemical VTE prophylaxis (6.7 ± 4.9 d versus 4.7 ± 4.9 d, P < 0.001) compared with those that did not develop a VTE. Also, for each 1 d increase in time to prophylaxis initiation, the odds of developing a VTE increased significantly (odds ratio = 1.055, P < 0.001). The combination subarachnoid hemorrhage/subdural hemorrhage group was started on VTE prophylaxis significantly later (8.3 ± 6.1 d versus 6.7 ± 3.9 d, P < 0.01) than the overall TBI group and had a higher incidence of VTE (14.4 versus 10.4%, P = NS). In contrast, patients sustaining isolated spinal injuries received chemical VTE prophylaxis significantly earlier (3.4 ± 4.2 d versus 6.7 ± 3.9 d, P < 0.001) and had a significant decrease in their VTE rate (4.4 versus 10.4%, P < 0.0001) compared with the overall TBI group.

CONCLUSIONS

Patients with VTEs had a significant delay in time to initiation of chemoprophylaxis compared with patients without VTEs. Patients sustaining a TBI had a 2-fold delay in initiation of chemoprophylaxis and an associated 2-fold increase in VTE events compared with patients who sustained spinal injuries. Of those patients who developed a TBI, patients who sustained a combination subarachnoid hemorrhage and/or subdural hemorrhage had a significant delay in initiation of chemoprophylaxis with a higher rate of VTE events.

Therapeutic anticoagulation in patients with traumatic brain injury

BACKGROUND

Therapeutic anticoagulation (TAC) is often required in trauma patients for various indications. However, it remains unknown whether TAC can be safely initiated in the postinjury period for patients with traumatic brain injury (TBI). The purpose of this study was to evaluate the safety of TAC in TBI patients.

MATERIALS AND METHODS

We conducted a 7-y retrospective study. All TBI patients who received TAC within 60 d postinjury were included. In addition to patient and injury characteristics, detailed information regarding TAC was collected. The primary outcome was the incidence of neurologic deterioration or progression of hemorrhagic TBI on repeat head computed tomography (CT) after initiation of TAC. Univariate and multivariate analyses were used to identify factors associated with progression of hemorrhagic TBI after TAC.

RESULTS

A total of 3355 TBI patients were identified. Of those, 72 patients (2.1%) received TAC. Median age, 59; 76.4% male; median Injury Severity Score, 19; median admission Glasgow Coma Scale, 14; and median Rotterdam score on the initial head CT, 3. Although atrial fibrillation was the most common preinjury indication for TAC, venous thromboembolism was the most common postinjury indication. The median postinjury time of initiation of TAC was 9 d. Intravenous heparin infusion was the most commonly used agent for TAC (70.8%). None of our study patients developed any signs of neurologic deterioration due to TAC. Progression of hemorrhagic TBI on repeat head CT was observed in six patients. In a multiple logistic regression model, aged ≥65 y was significantly associated with progression of hemorrhagic TBI after TAC (odds ratio, 15.2; 95% confidence interval, 1.1-212.7; P = 0.04).

CONCLUSIONS

This study shows preliminary data regarding TAC initiated in patients with TBI. Further prospective study is warranted to determine the risks and benefits of TAC in this specific group of patients.

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.

Anticoagulation Therapy in Traumatic Brain Injury

BACKGROUND

Optimal anticoagulation therapy (AT) in patients with traumatic brain injury (TBI) is a challenging task and proper management is strongly correlated with clinical outcomes. Only limited data are available on AT after TBI and practical decision making is based on the opinion of experts. This review sought to critically assess different therapeutic options using AT and antiplatelet agents in the perioperative period after TBI.

METHODS

A comprehensive review of the literature was performed to summarize relevant data on AT in patients with TBI.

RESULTS

Patients with preinjury AT with TBI require emergent neurosurgical treatment and they are also at high risk of developing thromboembolic complications or hematoma expansion. New oral anticoagulants offer a lower incidence of intracranial hemorrhage compared with warfarin. The rate of intracranial hemorrhage during new oral anticoagulants or heparin therapy is significantly lower than that with vitamin K antagonists.

Enoxaparin ameliorates post-traumatic brain injury edema and neurologic recovery, reducing cerebral leukocyte endothelial interactions and vessel permeability in vivo

BACKGROUND

Traumatic brain injury (TBI) confers a high risk of venous thrombosis, but early prevention with heparinoids is often withheld, fearing cerebral hematoma expansion. Yet, studies have shown heparinoids not only to be safe but also to limit brain edema and contusion size after TBI. Human TBI data also suggest faster radiologic and clinical neurologic recovery with earlier heparinoid administration. We hypothesized that enoxaparin (ENX) after TBI blunts in vivo leukocyte (LEU) mobilization to injured brain and cerebral edema, while improving neurologic recovery without increasing the size of the cerebral hemorrhagic contusion.

METHODS

CD1 male mice underwent either TBI by controlled cortical impact (CCI, 1-mm depth, 6 m/s) or sham craniotomy. ENX (1 mg/kg) or vehicle (VEH, 0.9% saline, 1 mL/kg) was administered at 2, 8, 14, 23, and 32 hours after TBI. At 48 hours, intravital microscopy was used to visualize live LEUs interacting with endothelium and microvascular leakage of fluorescein isothiocyanate-albumin. Neurologic function (Neurological Severity Score, NSS), activated clotting time, hemorrhagic contusion size, as well as brain and lung wet-to-dry ratios were evaluated post mortem. Analysis of variance with Bonferroni correction was used for statistical comparisons between groups.

RESULTS

Compared with VEH, ENX significantly reduced in vivo LEU rolling on endothelium (72.7 ± 28.3 LEU/100 μm/min vs. 30.6 ± 18.3 LEU/100 μm/min, p = 0.02) and cerebrovascular albumin leakage (34.5% ± 8.1% vs. 23.8% ± 5.5%, p = 0.047). CCI significantly increased ipsilateral cerebral hemisphere edema, but ENX treatment reduced post-CCI edema to near control levels (81.5% ± 1.5% vs. 77.6% ± 0.6%, p < 0.01). Compared with VEH, ENX reduced body weight loss at 24 hours (8.7% ± 1.2% vs. 5.8% ± 1.1%, p < 0.01) and improved NSS at 24 hours (14.5 ± 0.5 vs. 16.2 ± 0.4, p < 0.01) and 48 hours (15.1 ± 0.4 vs. 16.7 ± 0.5, p < 0.01) after injury. There were no significant differences in activated clotting time, hemorrhagic contusion size, and lung water content between the groups.

CONCLUSION

ENX reduces LEU recruitment to injured brain, diminishing visible microvascular permeability and edema. ENX may also accelerate neurologic recovery without increasing cerebral contusion size. Further study in humans is necessary to determine safety, appropriate dosage, and timing of ENX administration early after TBI.

Antiplatelet and anticoagulant therapy after intracerebral hemorrhage

Management of patients with an indication for long-term oral antithrombotic therapy who have an intracerebral hemorrhage (ICH) presents a therapeutic dilemma. Should antithrombotic therapy be resumed, and if so, when, using what agent, and for whom? There is no consensus for answers to these questions. In the absence of randomized trials, management of antithrombotic therapy after ICH is based on a combination of observational data, pathophysiologic concepts, and decision analysis. At the heart of the decision is an assessment of the individual patient's risk of thromboembolism off antithrombotic therapy versus risk of ICH recurrence on antithrombotic therapy.