Early Venous Thromboembolism Prophylaxis With Enoxaparin in Patients With Blunt Traumatic Brain Injury

The 2023 WSES guidelines on the management of trauma in elderly and frail patients

BACKGROUND

The trauma mortality rate is higher in the elderly compared with younger patients. Ageing is associated with physiological changes in multiple systems and correlated with frailty. Frailty is a risk factor for mortality in elderly trauma patients. We aim to provide evidence-based guidelines for the management of geriatric trauma patients to improve it and reduce futile procedures.

METHODS

Six working groups of expert acute care and trauma surgeons reviewed extensively the literature according to the topic and the PICO question assigned. Statements and recommendations were assessed according to the GRADE methodology and approved by a consensus of experts in the field at the 10th international congress of the WSES in 2023.

RESULTS

The management of elderly trauma patients requires knowledge of ageing physiology, a focused triage, including drug history, frailty assessment, nutritional status, and early activation of trauma protocol to improve outcomes. Acute trauma pain in the elderly has to be managed in a multimodal analgesic approach, to avoid side effects of opioid use. Antibiotic prophylaxis is recommended in penetrating (abdominal, thoracic) trauma, in severely burned and in open fractures elderly patients to decrease septic complications. Antibiotics are not recommended in blunt trauma in the absence of signs of sepsis and septic shock. Venous thromboembolism prophylaxis with LMWH or UFH should be administrated as soon as possible in high and moderate-risk elderly trauma patients according to the renal function, weight of the patient and bleeding risk. A palliative care team should be involved as soon as possible to discuss the end of life in a multidisciplinary approach considering the patient's directives, family feelings and representatives' desires, and all decisions should be shared.

CONCLUSIONS

The management of elderly trauma patients requires knowledge of ageing physiology, a focused triage based on assessing frailty and early activation of trauma protocol to improve outcomes. Geriatric Intensive Care Units are needed to care for elderly and frail trauma patients in a multidisciplinary approach to decrease mortality and improve outcomes.

Saudi Critical Care Society clinical practice guidelines on the prevention of venous thromboembolism in adults with trauma: reviewed for evidence-based integrity and endorsed by the Scandinavian Society of Anaesthesiology and Intensive Care Medicine

BACKGROUND

To develop evidence-based clinical practice guidelines on venous thromboembolism (VTE) prevention in adults with trauma in inpatient settings.

METHODS

The Saudi Critical Care Society (SCCS) sponsored guidelines development and included 22 multidisciplinary panel members who completed conflict-of-interest forms. The panel developed and answered structured guidelines questions. For each question, the literature was searched for relevant studies. To summarize treatment effects, meta-analyses were conducted or updated. Quality of evidence was assessed using the Grading Recommendations, Assessment, Development, and Evaluation (GRADE) approach, then the evidence-to-decision (EtD) framework was used to generate recommendations. Recommendations covered the following prioritized domains: timing of pharmacologic VTE prophylaxis initiation in non-operative blunt solid organ injuries; isolated blunt traumatic brain injury (TBI); isolated blunt spine trauma or fracture and/or spinal cord injury (SCI); type and dose of pharmacologic VTE prophylaxis; mechanical VTE prophylaxis; routine duplex ultrasonography (US) surveillance; and inferior vena cava filters (IVCFs).

RESULTS

The panel issued 12 clinical practice recommendations-one, a strong recommendation, 10 weak, and one with no recommendation due to insufficient evidence. The panel suggests starting early pharmacologic VTE prophylaxis for non-operative blunt solid organ injuries, isolated blunt TBIs, and SCIs. The panel suggests using low molecular weight heparin (LMWH) over unfractionated heparin (UFH) and suggests either intermediate-high dose LMWH or conventional dosing LMWH. For adults with trauma who are not pharmacologic candidates, the panel strongly recommends using mechanical VTE prophylaxis with intermittent pneumatic compression (IPC). The panel suggests using either combined VTE prophylaxis with mechanical and pharmacologic methods or pharmacologic VTE prophylaxis alone. Additionally, the panel suggests routine bilateral lower extremity US in adults with trauma with elevated risk of VTE who are ineligible for pharmacologic VTE prophylaxis and suggests against the routine placement of prophylactic IVCFs. Because of insufficient evidence, the panel did not issue any recommendation on the use of early pharmacologic VTE prophylaxis in adults with isolated blunt TBI requiring neurosurgical intervention.

CONCLUSION

The SCCS guidelines for VTE prevention in adults with trauma were based on the best available evidence and identified areas for further research. The framework may facilitate adaptation of recommendations by national/international guideline policymakers.

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.

Progression of Intracranial Hemorrhage After Chemical Prophylaxis Using Low-Molecular-Weight Heparin in Patients With Traumatic Brain Injury

INTRODUCTION

Chemical prophylaxis using low-molecular-weight heparin (LMWH) is considered a standard of care for venous thromboembolism in trauma patients. Our center performs a head computed tomography (CT) scan 24 hours after initiation with prophylactic LMWH in the setting of a known traumatic brain injury (TBI). The purpose was to determine the overall incidence of ICH progression after chemoprophylaxis in patients with a TBI.

METHODS

This retrospective study was performed at a Level I trauma center, from 1/1/2014 to 12/31/2017. Study patients were drawn from the institution's trauma registry based on Abbreviated Injury Score codes.

RESULTS

778 patients met all inclusion criteria after initial chart review. The proportion of patients with an observed radiographic progression of intracranial hemorrhage after LMWH was 5.8%. 3.1% of patients had a change in clinical management. Observed radiographic progression after LMWH prophylaxis and the presence of SDH on initial CT, the bilateral absence of pupillary response in the emergency department, and a diagnosis of dementia were found to have statistically significant correlation with bleed progression after LMWH was initiated.

CONCLUSION

Over a 4-year period, the use of CT to evaluate for radiographic progression of traumatic intracranial hemorrhage 24 hours after receiving LMWH resulted in a change in clinical management for 3.1% of patients. The odds of intracranial hemorrhage progression were approximately 6.5× greater in patients with subdural hemorrhage on initial CT, 3.1× greater in patients with lack of bilateral pupillary response in ED, and 4.2× greater in patients who had been diagnosed with dementia.

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.

Venous Thromboembolism in Trauma: The Role of Anticoagulation and Inferior Vena Cava Filters

Venous thromboembolism (VTE) is a significant contributor to morbidity and mortality among patients with severe trauma. Historically, prophylactic inferior vena cava filters (IVCFs) were used in high-risk trauma patients with suspected risk factors for VTE, including prolonged immobilization, and concurrent contraindication to anticoagulation. Mounting data regarding the efficacy of IVCF in this cohort, as well as concerns regarding morbidity of an in situ IVCF, have challenged this practice paradigm. In this review, we discuss the comanagement of VTE and trauma, including anticoagulation and the use of IVCF.

Early Chemoprophylaxis Against Venous Thromboembolism in Patients With Traumatic Brain Injury

INTRODUCTION

Timing to start of chemoprophylaxis for venous thromboembolism (VTE) in patients with traumatic brain injury (TBI) remains controversial. We hypothesize that early administration is not associated with increased intracranial hemorrhage.

METHODS

A retrospective study of adult patients with TBI following blunt injury was performed. Patients with penetrating brain injury, any moderate/severe organ injury other than the brain, need for craniotomy/craniectomy, death within 24 hours of admission, or progression of bleed on 6 hour follow-up head computed tomography scan were excluded. Patients were divided into early (≤24 hours) and late (>24 hours) cohorts based on time to initiation of chemoprophylaxis. Progression of bleed was the primary outcome.

RESULTS

264 patients were enrolled, 40% of whom were in the early cohort. The average time to VTE prophylaxis initiation was 17 hours and 47 hours in the early and late groups, respectively (P < .0001). There was no difference in progression of bleed (5.6% vs. 7%, P = .67), craniectomy/-craniotomy rate (1.9% vs. 2.5%, P = .81), or VTE rate (0% vs. 2.5%, P = .1).

CONCLUSION

Early chemoprophylaxis is not associated with progression of hemorrhage or need for neurosurgical intervention in patients with TBI and a stable head CT 7 hours following injury.

A Stitch in Time Saves Clots: Venous Thromboembolism Chemoprophylaxis in Traumatic Brain Injury

BACKGROUND

Venous thromboembolism chemoprophylaxis (VTE-CHEMO) is often delayed in patients with traumatic brain injury because of the concern for intracranial hemorrhage (ICH) progression. We hypothesize that (1) late time to VTE-CHEMO (≥48 h) is associated with higher incidence of VTE, and (2) VTE-CHEMO use does not correlate with ICH progression.

MATERIALS AND METHODS

This is a multiinstitutional retrospective study of patients with traumatic brain injury admitted between 2014 and 2016. Inclusion criteria were head Abbreviated Injury Code ≥2, ICH present on initial head computed tomography, and two or more head computed tomography scans after admission. The primary outcome was VTE, and the secondary outcome was ICH progression. Patients were classified as receiving VTE-CHEMO early (<48 h) or late (≥48 h). Multivariable analysis with Cox proportional hazards regression was performed.

RESULTS

Overall, 1803 patients were included. Patients with VTE (n = 137) were more likely to have spinal cord injury, blunt cerebrovascular injury, pelvic or femur fractures, and missed VTE-CHEMO doses. After multivariable regression, body mass index >30 (hazard ratio [HR], 1.05; P = 0.002), Injury Severity Score (HR, 1.004; P < 0.001), pelvic or femur fractures (HR, 1.05; P < 0.0001), spinal cord injury (HR, 1.28; P = 0.02), and missed VTE-CHEMO doses (HR, 1.08; P = 0.01) were significant predictors of VTE. In those who required neurosurgery, late VTE-CHEMO predicted VTE (HR, 1.21; P = 0.0001). Overall, 32% patients experienced ICH progression, which did not correlate with VTE-CHEMO use or timing.

CONCLUSIONS

This multicenter study highlights benefits from early VTE-CHEMO and identifies high-risk groups who may benefit from more aggressive prophylaxis. These data also emphasize risk to patients by withholding VTE-CHEMO.

Implementation of a Prophylactic Anticoagulation Guideline for Patients with Traumatic Brain Injury

BACKGROUND

Patients with traumatic brain injury (TBI) are at an increased risk of developing complications from venous thromboembolisms (VTEs [blood clots]). Benchmarking by the American College of Surgeons Trauma Quality Improvement Program identified suboptimal use of prophylactic anticoagulation in patients with TBI. We hypothesized that institutional implementation of an anticoagulation protocol would improve clinical outcomes in such patients.

METHODS

A new prophylactic anticoagulation protocol that incorporated education, weekly audits, and real-time adherence feedback was implemented in July 2015. The trauma registry identified patients with TBI before (PRE) and after (POST) implementation. Multivariable regression analysis with risk adjustment was used to compare use of prophylactic anticoagulation, VTE events, and mortality.

RESULTS

A total of 681 patients with TBI (368 PRE, 313 POST) were identified. After implementation of the VTE protocol, more patients received anticoagulation (PRE: 39.4%, POST: 80.5%, p < 0.001), time to initiation was shorter (PRE: 140 hours, POST: 59 hours, p < 0.001), and there were fewer VTE events (PRE: 19 [5.2%], POST: 7 [2.2%], p = 0.047). Multivariable analysis showed that POST patients were more likely to receive anticoagulation (odds ratio [OR] = 10.8, 95% confidence interval [CI] = 6.9-16.7, p < 0.001) and less likely to develop VTE (OR = 0.33, 95% CI = 0.1-1.0, p = 0.05).

CONCLUSION

Benchmarking can assist institutions to identity potential clinically relevant areas for quality improvement in real time. Combining education and multifaceted protocol implementation can help organizations to better focus limited quality resources and counteract barriers that have hindered adoption of best practices.

Practice Variation in Vena Cava Filter Use Among Trauma Centers in the National Trauma Database

BACKGROUND

Agreement regarding indications for vena cava filter (VCF) utilization in trauma patients has been in flux since the filter's introduction. As VCF technology and practice guidelines have evolved, the use of VCF in trauma patients has changed. This study examines variation in VCF placement among trauma centers.

MATERIALS AND METHODS

A retrospective study was performed using data from the National Trauma Data Bank (2005-2014). Trauma centers were grouped according to whether they placed VCFs during the study period (VCF+/VCF-). A multivariable probit regression model was fit to predict the number of VCFs used among the VCF+ centers (the expected [E] number of VCF per center). The ratio of observed VCF placement (O) to expected VCFs (O:E) was computed and rank ordered to compare interfacility practice variation.

RESULTS

In total, 65,482 VCFs were placed by 448 centers. Twenty centers (4.3%) placed no VCFs. The greatest predictors of VCF placement were deep vein thrombosis, spinal cord paralysis, and major procedure. The strongest negative predictor of VCF placement was admission during the year 2014. Among the VCF+ centers, O:E varied by nearly 500%. One hundred fifty centers had an O:E greater than one. One hundred sixty-nine centers had an O:E less than one.

CONCLUSIONS

Substantial variation in practice is present in VCF placement. This variation cannot be explained only by the characteristics of the patients treated at these centers but could be also due to conflicting guidelines, changing evidence, decreasing reimbursement rates, or the culture of trauma centers.

It's sooner than you think: Blunt solid organ injury patients are already hypercoagulable upon hospital admission - Results of a bi-institutional, prospective study

INTRODUCTION

The optimal time to initiate venous thromboembolism (VTE) chemoprophylaxis in blunt solid organ injury (BSOI) patients is debated. We hypothesize that 1) BSOI patients are hypercoagulable within 12 h of injury and 2) hypercoagulability dominates in patients who develop clot complications (CC).

MATERIAL AND METHODS

This is a prospective study of BSOI patients admitted to two Level-1 Trauma Centers' trauma intensive care units (ICU). Serial kaolin thrombelastography (TEG) and tissue plasminogen activator (tPA)-challenge TEGs were performed. CC included VTE and cerebrovascular accidents.

RESULTS

On ICU admission, all patients (n = 95) were hypercoagulable, 58% were in fibrinolysis shutdown, and 50% of patients were tPA-resistant. Twelve patients (13%) developed CC. Compared to those without CC, they demonstrated decreased fibrinolysis at 12 h and higher clot strength at 48 h CONCLUSIONS: BSOI patients are universally hypercoagulable upon ICU admission. VTE chemoprophylaxis should be started immediately in BSOI patients with hypercoagulability on TEG.

Venous thromboembolism (VTE) prophylaxis in severely injured patients: an international comparative assessment

PURPOSE

Venous thromboembolisms (VTE) are a major concern after acute survival from trauma. Variations in treatment protocols for trauma patients exist worldwide. This study analyzes the differences in the number of VTE events and the associated complications of thromboprophylaxis between two level I trauma populations utilizing varying treatment protocols.

METHODS

International multicenter trauma registry-based study was performed at the University Medical Center Utrecht (UMCU) in The Netherlands (early commencement chemical prophylaxis), and Harborview Medical Center (HMC) in the United States (restrictive early chemical prophylaxis). All severely injured patients (ISS ≥ 16), aged ≥ 18 years, and admitted in 2013 were included. Primary outcomes were VTE [deep venous thrombosis (DVT) (no screening), pulmonary embolism (PE)], and hemorrhagic complications.

RESULTS

In UMCU, 279 patients were included and in HMC, 974 patients. Overall, 75% of the admitted trauma patients in UMCU and 81% in HMC (p < 0.001) received thromboprophylaxis, of which 100% in and 75% at, respectively, UMCU and HMC consisted of chemical prophylaxis. From these patients, 72% at UMCU and 47% at HMC (p < 0.001) were treated within 48 h after arrival. At UMCU, 4 patients (1.4%) (PE = 3, DVT = 1) and HMC 37 patients (3.8%) (PE = 22, DVT = 16; p = 0.06) developed a VTE. At UMCU, a greater percent of patients with VTE had traumatic brain injuries (TBI). Most VTE occurred despite adequate prophylaxis being given (75% UMCU and 81% HMC). Hemorrhagic complications occurred in, respectively, 4 (1.4%) and 10 (1%) patients in UMCU and HMC (p = 0.570). After adjustment for age, ISS, HLOS, and injury type, no significant difference was demonstrated in UMCU compared to HMC for the development of VTE, OR 2.397, p = 0.102 and hemorrhagic complications, OR 0. 586, p = 0.383.

CONCLUSIONS

A more early commencement protocol resulted in almost twice as much chemical prophylaxis being started within the first 48 h in comparison with a more delayed initiation of treatment. Interestingly, most episodes of VTE developed while receiving recommended prophylaxis. Early chemical thromboprophylaxis did not significantly increase the bleeding complications and it appears to be safe to start early.

“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.

Diagnostic and therapeutic approach in adult patients with traumatic brain injury receiving oral anticoagulant therapy: an Austrian interdisciplinary consensus statement

There is a high degree of uncertainty regarding optimum care of patients with potential or known intake of oral anticoagulants and traumatic brain injury (TBI). Anticoagulation therapy aggravates the risk of intracerebral hemorrhage but, on the other hand, patients take anticoagulants because of an underlying prothrombotic risk, and this could be increased following trauma. Treatment decisions must be taken with due consideration of both these risks. An interdisciplinary group of Austrian experts was convened to develop recommendations for best clinical practice. The aim was to provide pragmatic, clear, and easy-to-follow clinical guidance for coagulation management in adult patients with TBI and potential or known intake of platelet inhibitors, vitamin K antagonists, or non-vitamin K antagonist oral anticoagulants. Diagnosis, coagulation testing, and reversal of anticoagulation were considered as key steps upon presentation. Post-trauma management (prophylaxis for thromboembolism and resumption of long-term anticoagulation therapy) was also explored. The lack of robust evidence on which to base treatment recommendations highlights the need for randomized controlled trials in this setting.

Anticoagulant prophylaxis against venous thromboembolism following severe traumatic brain injury: A prospective observational study and systematic review of the literature

OBJECTIVES

Venous thromboembolism (VTE) is a serious complication following severe traumatic brain injury (TBI), however, anticoagulant prophylaxis remains controversial due to concerns of intracranial hemorrhage (ICH) progression. We examined anticoagulant prophylaxis practice patterns at a major trauma centre and determined risk estimates for VTE and ICH progression classified by timing of anticoagulant initiation.

PATIENTS AND METHODS

A 1-year prospective analysis of consecutive patients with severe TBI admitted to a Level-I trauma centre was conducted. In addition, we systematically reviewed the literature to identify studies on VTE and anticoagulant prophylaxis after severe TBI.

RESULTS

64 severe TBI patients were included. 83% of patients received anticoagulant prophylaxis, initiated ≥3d post-TBI in 67%. The in-hospital VTE incidence was 16% and there was no significant difference between patients who received early (<3d) versus late (≥3d) prophylaxis (10% vs. 16%). Rates of ICH progression (0% vs. 7%) were similar between groups. Our systematic review identified 5 studies with VTE rates ranging from 5 to 10% with prophylaxis, to 11-30% without prophylaxis. The effect of timing of anticoagulant prophylaxis initiation on ICH progression was not reported in any study.

CONCLUSION

VTE is a common complication after severe TBI. Anticoagulant prophylaxis is often started late (≥3d) post-injury. Randomized trials are justifiable and necessary to provide practice guidance with regards to optimal timing of anticoagulant prophylaxis.

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.

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.

[Posttraumatic thromboembolic complications: Incidence, risk factors, pathophysiology and prevention]

Venous thromboembolism (VTE) remains a major challenge in critically ill patients. Subjects admitted in intensive care unit (ICU), in particular trauma patients, are at high-risk for both deep vein thrombosis (DVT) and pulmonary embolism (PE). The rate of symptomatic PE in injured patients has been reported previously ranging from 1 to 6%. The high incidence of posttraumatic venous thromboembolic events is well known. In fact, major trauma is a hypercoagulable state. Several factors placing the individual patient at a higher risk for the development of DVT and PE have been suggested: high ISS score, meningeal hemorrhage and spinal cord injuries have frequently been reported as a significant risk factor for VTEs after trauma. Posttraumatic pulmonary embolism traditionally occurs after a period of at least 5 days from trauma. The prevention can reduce the incidence and mortality associated with the pulmonary embolism if it is effective. There is no consensus is now available about the prevention of venous thromboembolism in trauma patients.

Lethal Trauma Pulmonary Embolism is a Black Swan Event in Patients at Risk for Deep Vein Thrombosis: An Evidence-Based Review

We delineated the incidence of trauma patient pulmonary embolism (PE) and risk conditions by performing a systematic literature review of those at risk for deep vein thrombosis (DVT). The PE proportion was 1.4 per cent (95% confidence interval = 1.2–1.6) in at-risk patients. Of 10 conditions, PE was only associated with increased age (P < 0.01) or leg injury (P < 0.01; risk ratio = 1.6). As lower extremity DVT (LEDVT) proportions increased, mortality proportions (P = 0.02) and hospital stay (P = 0.0002) increased, but PE proportions did not (P = 0.13). LEDVT was lower with chemoprophylaxis (CP) (4.9%) than without CP (19.1%; P < 0.01). PEwas lower withCP (1.0%) than without CP (2.2%; P = 0.0004). Mortality was lower with CP (6.6%) than without CP (11.6%; P = 0.002). PE was similar with (1.2%) and without (1.9%; P = 0.19) mechanical prophylaxis (MP). LEDVT was lower with MP (8.5%) than without MP (12.2%; P = 0.0005). PE proportions were similar with (1.3%) and without (1.5%; P = 0.24) LEDVTsurveillance. Mortality was higher with LEDVTsurveillance (7.9%) than without (4.8%; P < 0.01). A PE mortality of 19.7 per cent (95% confidence interval = 18–22) 3 a 1.4 per cent PE proportion yielded a 0.28 per cent lethal PE proportion. As PE proportions increased, mortality (P = 0.52) and hospital stay (P = 0.13) did not. Of 176 patients with PE, 76 per cent had no LEDVT. In trauma patients at risk for DVT, PE is infrequent, has a minimal impact on outcomes, and death is a black swan event. LEDVTsurveillance did not improve outcomes. Because PE was not associated with LEDVT and most patients with PE had no LEDVT, preventing, diagnosing, and treating LEDVT may be ineffective PE prophylaxis.

Does enoxaparin interfere with HMGB1 signaling after TBI? A potential mechanism for reduced cerebral edema and neurologic recovery

BACKGROUND

Enoxaparin (ENX) has been shown to reduce cerebral edema and improve neurologic recovery after traumatic brain injury (TBI), through blunting of cerebral leukocyte (LEU) recruitment. High mobility group box 1 (HMGB1) protein may induce inflammation through LEU activation. We hypothesized that ENX after TBI reduces LEU-mediated edema through blockade of HMGB1 signaling.

METHODS

Twenty-three CD1 mice underwent severe TBI by controlled cortical impact and were randomized to one of four groups receiving either monoclonal antibody against HMGB1 (MAb) or isotype (Iso) and either ENX (1 mg/kg) or normal saline (NS): NS + Iso (n = 5), NS + MAb (n = 6), ENX + Iso (n = 6), ENX + MAb (n = 6). ENX or NS was administered 2, 8, 14, 23 and 32 hours after TBI. MAb or Iso (25 μg) was administered 2 hours after TBI. At 48 hours, cerebral intravital microscopy served to visualize live LEU interacting with endothelium and microvascular fluorescein isothiocyanate-albumin leakage. The Neurological Severity Score (NSS) graded neurologic recovery; wet-to-dry ratios determined cerebral/lung edema. Analysis of variance with Bonferroni correction was used for statistical analyses.

RESULTS

ENX and MAb similarly reduced in vivo pial LEU rolling without demonstrating additive effect. In vivo albumin leakage was greatest in vehicle-treated animals but decreased by 25% with either MAb or ENX but by 50% when both were combined. Controlled cortical impact-induced cerebral wet-to-dry ratios were reduced by MAb or ENX without additive effect. Postinjury lung water was reduced by ENX but not by MAb. Neurologic recovery at 24 hours and 48 hours was similarly improved with ENX, MAb, or both treatments combined.

CONCLUSION

Mirroring ENX, HMGB1 signaling blockade reduces LEU recruitment, cerebrovascular permeability, and cerebral edema following TBI. ENX further reduced lung edema indicating a multifaceted effect beyond HMGB1 blockade. Further study is needed to determine how ENX may play a role in blunting HMGB1 signaling in brain injury patients.

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

OBJECTIVE

To synthesize the existing literature on benefits and risks of anticoagulant use after traumatic brain injury (TBI).

DESIGN

Systematic review. A literature search was performed in MEDLINE, International Pharmaceutical Abstracts, Health Star, and CINAHL (Cumulative Index to Nursing and Allied Health Literature) on October 11, 2012, and updated on September 2, 2013, using terms related to TBI and anticoagulants.

MAIN MEASURES

Human studies evaluating the effects of post-TBI anticoagulation on venous thromboembolism, hemorrhage, mortality, or coagulation parameters with original analyses were eligible for the review. PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guideline was followed throughout the conduct of the review.

RESULTS

Thirty-nine eligible studies were identified from the literature, of which 23 studies with complete information on post-TBI anticoagulant use and patient outcomes were summarized in this review. Meta-analysis was unwarranted because of varying methodological design and quality of the studies. Twenty-one studies focused on the effects of pharmacological thromboprophylaxis (PTP) post-TBI on venous thromboembolism and/or progression of intracranial hemorrhage, whereas 2 randomized controlled trials analyzed coagulation parameters as the result of anticoagulation.

CONCLUSION

Pharmacological thromboprophylaxis appears to be safe among TBI patients with stabilized hemorrhagic patterns. More evidence is needed regarding effectiveness of PTP in preventing venous thromboembolism as well as preferred agent, dose, and timing for PTP.

Timing for deep vein thrombosis chemoprophylaxis in traumatic brain injury: an evidence-based review

Multiple studies have addressed deep vein thrombosis chemoprophylaxis timing in traumatic brain injuries. However, a precise time for safe and effective chemoprophylaxis is uncertain according to experts. A comprehensive literature review on brain injuries was performed to delineate temporal proportions for 1) spontaneous intracranial hemorrhage (ICH) progression, 2) post-chemoprophylaxis ICH expansion, and 3) post-chemoprophylaxis deep vein thrombosis. Twenty-three publications were found including more than 5,000 patients. Spontaneous ICH expansion at 24 hours was 14.8% in 1,437 patients from chemoprophylaxis studies and 29.9% in 1,257 patients not in chemoprophylaxis studies (P < 0.0001). With low-risk ICH (n = 136), 99% of spontaneous ICH expansion occurred within 48 hours. In moderate or high-risk ICH (n = 109), 18% of spontaneous ICH expansion occurred after day 3. If patients with pre-chemoprophylaxis ICH expansion are included, the post-chemoprophylaxis ICH expansion proportion was 5.6% in 1,258 patients with chemoprophylaxis on days 1 to 3 and was 1.5% in 401 with chemoprophylaxis after day 3 (P = 0.0116). If patients with pre-chemoprophylaxis ICH expansion were excluded, the post-chemoprophylaxis ICH expansion proportion was 3.1% in 1,570 patients with chemoprophylaxis on days 1 to 3 and was 2.8% in 582 with chemoprophylaxis after day 3 (P = 0.7769). In diffuse axonal injury (n = 188), the post-chemoprophylaxis ICH expansion proportion was 1.6% with chemoprophylaxis after day 3. The deep vein thrombosis proportions were as follows: chemoprophylaxis on days 1 to 3, 2.6% in 2,384 patients; chemoprophylaxis on days 4 or 5, 2.2% in 831; and chemoprophylaxis on day 8, 14.1% in 99 (P < 0.0001). Spontaneous ICH expansion proportions at 24 hours substantially vary between chemoprophylaxis and non-chemoprophylaxis studies. Chemoprophylaxis should not be given within 3 days of injury for moderate-risk or high-risk ICH. Chemoprophylaxis is reasonable when low-risk patients have not developed ICH expansion within 48 hours post-injury. Chemoprophylaxis is also acceptable after day 3, when low-risk patients develop ICH expansion within 48 hours post-injury. In diffuse axonal injury patients who have not developed ICH within 72 hours, chemoprophylaxis is reasonable. Deep vein thrombosis proportions significantly increase when chemoprophylaxis is withheld for greater than 7 days.

The Parkland Protocol's modified Berne-Norwood criteria predict two tiers of risk for traumatic brain injury progression

As a basis for venous thromboembolism (VTE) prophylaxis after traumatic brain injury (TBI), we have previously published an algorithm known as the Parkland Protocol. Patients are classified by risk for spontaneous progression of hemorrhage with chemoprophylaxis regimens tailored to each tier. We sought to validate this schema. In our algorithm, patients with any of the following are classified "low risk" for spontaneous progression: subdural hemorrhage ≤8 mm thick; epidural hemorrhage ≤8 mm thick; contusions ≤20 mm in diameter; a single contusion per lobe; any amount of subarachnoid hemorrhage; or any amount of intraventricular hemorrhage. Patients with any injury exceeding these are "moderate risk" for progression, and any patient receiving a monitor or craniotomy is "high risk." From February 2010 to November 2012, TBI patients were entered into a dedicated database tracking injury types and sizes, risk category at presentation, and progression on subsequent computed tomgraphies (CTs). The cohort (n=414) was classified as low risk (n=200), moderate risk (n=75), or high risk (n=139) after first CT. After repeat CT scan, radiographic progression was noted in 27% of low-risk, 53% of moderate-risk, and 58% of high-risk subjects. Omnibus analysis of variance test for differences in progression rates was highly significant (p<0.0001). Tukey's post-hoc test showed the low-risk progression rate to be significantly different than both the moderate- and high-risk arms; no difference was noted between the moderate- and high-risk arms themselves. These criteria are a valid tool for classifying TBI patients into two categories of risk for spontaneous progression. This supports tailored chemoprophylaxis regimens for each arm.

Early initiation of prophylactic heparin in severe traumatic brain injury is associated with accelerated improvement on brain imaging

Background:

Venous thromboembolic prophylaxis (VTEp) is often delayed following traumatic brain injury (TBI), yet animal data suggest that it may reduce cerebral inflammation and improve cognitive recovery. We hypothesized that earlier VTEp initiation in severe TBI patients would result in more rapid neurologic recovery and reduced progression of brain injury on radiologic imaging.

Study Design:

Medical charts of severe TBI patients admitted to a level 1 trauma center in 2009-2010 were queried for admission Glasgow Coma Scale (GCS), head Abbreviated Injury Scale, Injury Severity Score (ISS), osmotherapy use, emergency neurosurgery, and delay to VTEp initiation. Progression (+1 = better, 0 = no change, −1 = worse) of brain injury on head CTs and neurologic exam (by bedside MD, nurse) was collected from patient charts. Head CT scan Marshall scores were calculated from the initial head CT results.

Results:

A total of 22, 34, and 19 patients received VTEp at early (<3 days), intermediate (3-5 days), and late (>5 days) time intervals, respectively. Clinical and radiologic brain injury characteristics on admission were similar among the three groups (P > 0.05), but ISS was greatest in the early group (P < 0.05). Initial head CT Marshall scores were similar in early and late groups. The slowest progression of brain injury on repeated head CT scans was in the early VTEp group up to 10 days after admission.

Conclusion:

Early initiation of prophylactic heparin in severe TBI is not associated with deterioration neurologic exam and may result in less progression of injury on brain imaging. Possible neuroprotective effects of heparin in humans need further investigation.

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

OBJECT

Patients with traumatic brain injury (TBI) are at risk for development of thromboembolic disease. The use of chemoprophylaxis in this patient group has not fully been characterized. The authors hypothesize that early chemoprophylaxis in patients with TBI is safe and efficacious.

METHODS

In May 2009, a protocol was instituted for patients with TBI where chemoprophylaxis for thromboembolic disease (either 30 mg of Lovenox twice daily or 5000 U of heparin 3 times a day) was initiated 24 hours after an intracranial hemorrhage (ICH) was demonstrated as stable on head CT image. Two cohorts were evaluated: Cohort A included patients from May 2008 through April 2009 who had no routine administration of chemoprophylaxis, and Cohort B included patients from May 2009 through May 2010 after the protocol was instituted. The groups were compared, with the major outcomes being deep venous thrombosis (DVT), pulmonary embolism, and increase in size of ICH.

RESULTS

Of the 312 patients with TBI who were seen during the study course, 236 patients met criteria for inclusion in the study: 107 patients in Cohort A and 129 patients in Cohort B. The DVT rate was 6 occurrences (5.61%) in Cohort A and 0 occurrences (0%) in Cohort B, which was a statistically significant difference (p = 0.0080). Pulmonary embolism was found in 4 patients (3.74%) in Cohort A and 1 patient (0.78%) in Cohort B, a difference that did not reach statistical significance (p = 0.18). Three instances (2.8%) in Cohort A and 1 instance (0.7%) in Cohort B of increased ICH occurred after starting anticoagulation for chemoprophylaxis; this was not statistically different (p = 0.33).

CONCLUSIONS

Use of chemoprophylaxis in TBI 24 hours after stable head CT is safe and decreases the rate of DVT formation.

Management of simultaneous traumatic brain injury and aortic injury

Object

Simultaneous traumatic brain injury (TBI) and aortic injury has been considered unsurvivable for many years because treatments such as sedation and blood pressure goals conflict for these 2 conditions. Additionally, surgical interventions for aortic injury often require full anticoagulation, which is contraindicated in patients with TBI. For these reasons, and due to the relative rarity of aortic injury/TBI, little data are available to guide treating physicians.

Methods

A retrospective review was performed on all simultaneous TBI and aortic injury cases from 2000 to 2012 at a university-affiliated, Level I trauma center. Patient demographics, imaging studies, interventions, and outcomes were analyzed. Traumatic brain injury/aortic injury cases treated with endovascular stenting were specifically studied to determine trends in procedure timing, use of anticoagulation, and neurological outcome.

Results

Thirty-three patients with concurrent TBI and aortic injury were identified over a 12-year period. The median patient age was 44 years (range 16–86 years) and the overall mortality rate after imaging diagnosis was 46%. All surviving patients were awake and neurologically functional at discharge, and 83% were discharged home or to rehabilitation facilities. Patients who died had a higher Injury Severity Scale score (p = 0.006). Severe TBI (p = 0.045) or hemodynamic instability (p = 0.015) upon arrival to the hospital was also correlated with increased mortality rates. Thirty-three percent of aortic injury/TBI patients (n = 11) underwent endovascular stenting, and 7 of these patients received intravenous anticoagulation therapy at the time of surgery. Six of these 7 anticoagulation-treated patients experienced no significant progression on postoperative brain CT, whereas 1 patient died of hemodynamic instability prior to undergoing further imaging.

Conclusions

Simultaneous TBI and aortic injury is a rare condition with a historically poor prognosis. However, these results suggest that many patients can survive with a good quality of life. Technological advances such as endovascular aortic stenting may improve patient outcome, and anticoagulation is not absolutely contraindicated after TBI.

Pharmacologic venous thromboembolism prophylaxis after traumatic brain injury: a critical literature review

Despite the frequency and morbidity of venous thromboembolism (VTE) development after traumatic brain injury (TBI), no national standard of care exists to guide TBI caregivers for the use of prophylactic anticoagulation. Fears of iatrogenic propagation of intracranial hemorrhage patterns have led to a dearth of research in this field, and it is only relatively recently that studies dedicated to this question have been performed. These have generally been limited to retrospective and/or observational studies in which patients are classified in a binary fashion as having the presence or absence of intracranial blood. This methodology does not account for the fact that smaller injury patterns stabilize more rapidly, and thus may be able to safely tolerate earlier initiation of prophylactic anticoagulation than larger injury patterns. This review seeks to critically assess the literature on this question by examining the existing evidence on the safety and efficacy of pharmacologic VTE prophylaxis in the setting of elective craniotomy (as this is the closest model available from which to extrapolate) and after TBI. In doing so, we critique studies that approach TBI as a homogenous or a heterogenous study population. Finally, we propose our own theoretical protocol which stratifies patients into low, moderate, and high risk for the likelihood of natural progression of their hemorrhage pattern, and which allows one to tailor a unique VTE prophylaxis regimen to each individual arm.

Risk factors for venous thromboembolism in critically ill trauma patients who cannot receive chemical prophylaxis

BACKGROUND

Standard venous thromboembolism (VTE) prevention for critically ill trauma patients includes sequential compression devices and chemical prophylaxis. When contraindications to anticoagulation are present, prophylactic inferior vena cava filters (IVCF) may be used to prevent pulmonary emboli (PE) in high-risk patients, but specific indications are lacking. We sought to identify independent predictors of VTE in critically-ill trauma patients who cannot receive chemical prophylaxis in order to identify a subset of patients who may benefit from aggressive screening and/or prophylactic IVCF placement.

METHODS

All trauma patients in the surgical ICU from 2008 to 2009 were prospectively followed. Patients with an ICU length of stay ≥2 days who had contraindications to prophylactic anticoagulation were included. Screening duplex exams were obtained within 48 h of admission and then weekly. CT-angiography for PE was obtained if clinically indicated. Patients were excluded if they did not receive a duplex or if they had a post-injury VTE prior to ICU admission. Data regarding VTE rates (lower extremity [LE] DVT or PE), demographics, past medical history (PMH), injuries, and surgeries were collected. Univariate and multivariable analyses were performed to identify independent predictors of VTE with a p<0.05.

RESULTS

411 trauma patients with a mean age of 48 (SD 22) years and 8 (SD 9) ICU days were included. 72% were male and the mean ISS was 22 (SD 13). 30 (7.3%) patients developed VTE: 28 (6.8%) with LEDVT and 2 (0.5%) with PE. Risk factors for VTE with a p<0.2 on univariate analysis included: PMH of DVT, injury severity score (ISS), extremity fractures (Fx), and a pelvis or LE extremity Fx repair. After logistic regression, only PMH of DVT (OR=22.6) and any extremity Fx (OR=2.4) remained as independent predictors.

CONCLUSION

VTE occur in 7% of critically injured trauma patients who cannot receive chemical prophylaxis. Aggressive screening and/or prophylactic IVCF placement may be considered in patients with a PMH of DVT or extremity fractures when anticoagulation is prohibited.

Prevention of venous thrombotic events in brain injury: review of current practices

Venous thromboembolic event after traumatic brain injury represents a unique clinical challenge. Physicians must balance appropriate timing of chemoprophylaxis with risk of increased cerebral hemorrhage. Despite an increase in the literature since the 1990s, there are clear disparities in treatment strategies. This review discusses the prominent studies and subsequent findings regarding the topic with an attempt to establish recommendations using the existing evidence-based literature.

Controversies in the management of adults with severe traumatic brain injury

Despite progress in the management of adults with severe traumatic brain injury, several controversies persist. Among the unresolved issues of greatest concern to neurocritical care clinicians and scientists are the following: (1) the best use of technological advances and the data obtained from multimodality monitoring; (2) the use of mannitol and hypertonic saline in the management of increased intracranial pressure; (3) the use of decompressive craniectomy and barbiturate coma in refractory increased intracranial pressure; (4) therapeutic hypothermia as a neuroprotectant; (5) anemia and the role of blood transfusion; and (6) venous thromboembolism prophylaxis in severe traumatic brain injury. Each of these strategies for managing severe traumatic brain injury, including the postulated mechanism(s) of action and beneficial effects of each intervention, adverse effects, the state of the science, and critical care nursing implications, is discussed.

Post-traumatic pulmonary embolism in the intensive care unit

OBJECTIVE:

To determine the predictive factors, clinical manifestations, and the outcome of patients with post-traumatic pulmonary embolism (PE) admitted in the intensive care unit (ICU).

METHODS:

During a four-year prospective study, a medical committee of six ICU physicians prospectively examined all available data for each trauma patient in order to classify patients according to the level of clinical suspicion of pulmonary thromboembolism. During the study period, all trauma patients admitted to our ICU were classified into two groups. The first group included all patients with confirmed PE; the second group included patients without clinical manifestations of PE. The diagnosis of PE was confirmed either by a high-probability ventilation/perfusion (V/Q) scan or by a spiral computed tomography (CT) scan showing one or more filling defects in the pulmonary artery or its branches.

RESULTS:

During the study period, 1067 trauma patients were admitted in our ICU. The diagnosis of PE was confirmed in 34 patients (3.2%). The mean delay of development of PE was 11.3 ± 9.3 days. Eight patients (24%) developed this complication within five days of ICU admission. On the day of PE diagnosis, the clinical examination showed that 13 patients (38.2%) were hypotensive, 23 (67.7%) had systemic inflammatory response syndrome (SIRS), three (8.8%) had clinical manifestations of deep venous thrombosis (DVT), and 32 (94%) had respiratory distress requiring mechanical ventilation. In our study, intravenous unfractionated heparin was used in 32 cases (94%) and low molecular weight heparin was used in two cases (4%). The mean ICU stay was 31.6 ± 35.7 days and the mean hospital stay was 32.7 ± 35.3 days. The mortality rate in the ICU was 38.2% and the in-hospital mortality rate was 41%. The multivariate analysis showed that factors associated with poor prognosis in the ICU were the presence of circulatory failure (Shock) (Odds ratio (OR) = 9.96) and thrombocytopenia (OR = 32.5).Moreover, comparison between patients with and without PE showed that the predictive factors of PE were: Age > 40 years, a SAPS II score > 25, hypoxemia with PaO₂/FiO₂ < 200 mmHg, the presence of spine fracture, and the presence of meningeal hemorrhage.

CONCLUSION:

Despite the high frequency of DVT in post-traumatic critically ill patients, symptomatic PE remains, although not frequently observed, because systematic screening is not performed. Factors associated with poor prognosis in the ICU are the presence of circulatory failure (shock) and thrombocytopenia. Predictive factors of PE are: Age > 40 years, a SAPS II score > 25, hypoxemia with PaO₂/FiO₂ < 200, the presence of a spine fracture, and the presence of meningeal hemorrhage. Prevention is highly warranted.

Therapeutic anticoagulation can be safely accomplished in selected patients with traumatic intracranial hemorrhage

Introduction

Therapeutic anticoagulation is an important treatment of thromboembolic complications, such as DVT, PE, and blunt cerebrovascular injury. Traumatic intracranial hemorrhage has traditionally been considered to be a contraindication to anticoagulation.

Hypothesis

Therapeutic anticoagulation can be safely accomplished in select patients with traumatic intracranial hemorrhage.

Methods

Patients who developed thromboembolic complications of DVT, PE, or blunt cerebrovascular injury were stratified according to mode of treatment. Patients who underwent therapeutic anticoagulation with a heparin infusion or enoxaparin (1 mg/kg BID) were evaluated for neurologic deterioration or hemorrhage extension by CT scan.

Results

There were 42 patients with a traumatic intracranial hemorrhage that subsequently developed a thrombotic complication. Thirty-five patients developed a DVT or PE. Blunt cerebrovascular injury was diagnosed in four patients. 26 patients received therapeutic anticoagulation, which was initiated an average of 13 days after injury. 96% of patients had no extension of the hemorrhage after anticoagulation was started. The degree of hemorrhagic extension in the remaining patient was minimal and was not felt to affect the clinical course.

Conclusion

Therapeutic anticoagulation can be accomplished in select patients with intracranial hemorrhage, although close monitoring with serial CT scans is necessary to demonstrate stability of the hemorrhagic focus.

Pharmacological prophylaxis of venous thromboembolism during acute phase of spontaneous intracerebral hemorrhage: what do we know about risks and benefits?

Spontaneous intracerebral hemorrhage (sICH) represents a devastating clinical event with high mortality and morbidity rates. Only few patients with sICH are treated with neurosurgical evacuation of the hematoma, and the majority of them need only a good conservative medical approach. The goal of medical treatment is to avoid secondary neurological and systemic complications. Venous thromboembolism (VTE) represents one of the most feared complications of sICH, and it is a potential cause of death. The balance between the benefit of VTE prevention and the risk of hematoma enlargement and/or rebleeding with the use of pharmacologic thromboprophylaxis remains controversial because of the lack of consistent evidences in the literature. The efficacy of mechanical prophylaxis is also uncertain. Consequently, until now there are no clear guidelines and scientific evidences available for physicians in this field. The aim of this review is to analyze the available literature and guidelines about pharmacological VTE prophylaxis in patients with nonsurgical sICH.

Prevention of VTE in nonorthopedic surgical patients: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines

BACKGROUND

VTE is a common cause of preventable death in surgical patients.

METHODS

We developed recommendations for thromboprophylaxis in nonorthopedic surgical patients by using systematic methods as described in Methodology for the Development of Antithrombotic Therapy and Prevention of Thrombosis Guidelines. Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines in this supplement.

RESULTS

We describe several alternatives for stratifying the risk of VTE in general and abdominal-pelvic surgical patients. When the risk for VTE is very low (< 0.5%), we recommend that no specific pharmacologic (Grade 1B) or mechanical (Grade 2C) prophylaxis be used other than early ambulation. For patients at low risk for VTE (∼1.5%), we suggest mechanical prophylaxis, preferably with intermittent pneumatic compression (IPC), over no prophylaxis (Grade 2C). For patients at moderate risk for VTE (∼3%) who are not at high risk for major bleeding complications, we suggest low-molecular-weight heparin (LMWH) (Grade 2B), low-dose unfractionated heparin (Grade 2B), or mechanical prophylaxis with IPC (Grade 2C) over no prophylaxis. For patients at high risk for VTE (∼6%) who are not at high risk for major bleeding complications, we recommend pharmacologic prophylaxis with LMWH (Grade 1B) or low-dose unfractionated heparin (Grade 1B) over no prophylaxis. In these patients, we suggest adding mechanical prophylaxis with elastic stockings or IPC to pharmacologic prophylaxis (Grade 2C). For patients at high risk for VTE undergoing abdominal or pelvic surgery for cancer, we recommend extended-duration, postoperative, pharmacologic prophylaxis (4 weeks) with LMWH over limited-duration prophylaxis (Grade 1B). For patients at moderate to high risk for VTE who are at high risk for major bleeding complications or those in whom the consequences of bleeding are believed to be particularly severe, we suggest use of mechanical prophylaxis, preferably with IPC, over no prophylaxis until the risk of bleeding diminishes and pharmacologic prophylaxis may be initiated (Grade 2C). For patients in all risk groups, we suggest that an inferior vena cava filter not be used for primary VTE prevention (Grade 2C) and that surveillance with venous compression ultrasonography should not be performed (Grade 2C). We developed similar recommendations for other nonorthopedic surgical populations.

CONCLUSIONS

Optimal thromboprophylaxis in nonorthopedic surgical patients will consider the risks of VTE and bleeding complications as well as the values and preferences of individual patients.

Effects of enoxaparin in the rat hippocampus following traumatic brain injury

Purpose of this study was to investigate the effects of low molecular weight heparin, enoxaparin, on different parameters of the hippocampal damage following traumatic brain injury (TBI) in the rat. TBI of moderate severity was performed over the left parietal cortex using the lateral fluid percussion brain injury model. Animals were s.c. injected with either enoxaparin (1mg/kg) or vehicle 1, 7, 13, 19, 25, 31, 37, and 43 h after the TBI induction. Sham-operated, vehicle-treated animals were used as the control group. Rats were sacrificed 48h after the induction of TBI. Hippocampi were processed for spectrophotometric measurements of the products of oxidative lipid damage, thiobarbituric acid-reactive substances (TBARS) levels, as well as the activities of antioxidant enzymes, superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px). Moreover, the Western blotting analyses of the oxidized protein levels, expressions of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), pro- and mature-interleukin-1β (pro-, and mature-IL-1β), and active caspase-3 were performed. COX-2 expressions were also explored by using immunohistochemistry. Glial fibrillary acidic protein immunochistochemistry was performed with the aim to assess the level of astrocytic activity. Fluoro-Jade B staining was used to identify the level and extent of hippocampal neuronal injury. TBI caused statistically significant increases of the hippocampal TBARS and oxidized protein levels as well as COX-2, pro-IL-1β, and active caspase-3 overexpressions, but it did not significantly affect the SOD and GSH-Px activities, the iNOS, and mature-IL-1β expression levels. TBI also induced hippocampal reactive astrocytosis and neurodegeneration. Enoxaparin significantly decreased the hippocampal TBARS and oxidized protein levels, COX-2 overexpression and reactive gliosis, but it did not influence the SOD and GSH-Px activities, pro-IL-1β and active caspase-3 overexpressions as well as neurodegeneration following TBI. These findings demonstrate that enoxaparin may reduce oxidative damage, inflammation and astrocytosis following TBI in the rat and could be a candidate drug for neuroprotective treatment of this injury.

Vena cava interruption

Anticoagulation has been proven to be effective in preventing and treating deep vein thrombosis and pulmonary embolus. However, many critically ill patients are unable to receive anticoagulation or suffer recurrent venous thromboembolism despite adequate treatment. This article examines the use of vena cava filters in the critically ill. Indications for, techniques, and complications of vena cava filter insertion are reviewed. The importance of vena cava filters with the option to be retrieved and bedside insertion in the intensive care unit is emphasized.

Three thousand seven hundred thirty-eight posttraumatic pulmonary emboli: a new look at an old disease

OBJECTIVE

This study was undertaken to determine the current incidence of pulmonary embolism (PE) and its attributable mortality after injury.

BACKGROUND

Despite compliance with prophylactic measures, PE remains a threat to postinjury recovery. We hypothesized that the liberal use of chest computed tomography after injury has resulted in an increased rate of detection of PE but that the mortality attributable to PE has decreased over the past decade. We also postulated that the risk factors for posttraumatic PE might be different from those for deep venous thrombosis (DVT).

METHODS

We examined demographics, injury data, risk factors, and outcomes from patients with DVT and PE compiled in the recent years (2007-2009) in the National Trauma Data Bank (NTDB). For comparison, we used patient data entered into NTDB from 1994 to 2001. Statistical models were created to examine the predictors of DVT and PE and PE-related mortality.

RESULTS

Among 888,652 patients in the current NTDB cohort, there were 9398 episodes of DVT (1.06%) and 3738 of PE (0.42%). Although many risk factors overlapped, a severe chest injury (Abbreviated Injury Score ≥ 3) conferred a much higher risk of PE than DVT. When comparing results from centers that had contributed to both data sets, there was a more than 2-fold increase in PE occurrence in the current cohort (0.49% vs 0.21%, P < 0.01) but with a significant reduction in PE-adjusted mortality (odds ratio, 4.08 vs 2.42).

CONCLUSIONS

The reported incidence of PE after trauma has more than doubled in recent years, while the PE-associated mortality has significantly decreased, suggesting that we are identifying a different disease entity or stage. Chest injuries convey a substantial risk for PE, a risk not likely to be diminished by leg compression devices or vena cava filters.