Dalteparin vs low-dose unfractionated heparin for prophylaxis against clinically evident venous thromboembolism in acute traumatic spinal cord injury: a retrospective cohort study

Venous Thromboembolism Chemoprophylaxis in Trauma and Emergency General Surgery Patients: A Systematic Review

BACKGROUND

Appropriate venous thromboembolism (VTE) chemoprophylaxis in trauma and emergency general surgery (EGS) patients is crucial.

OBJECTIVE

The purpose of this study is to review the recent literature and offer recommendations for VTE chemoprophylaxis in trauma and EGS patients.

METHODS

We conducted a literature search from 2000 to 2021 for articles investigating VTE chemoprophylaxis in adult trauma and EGS patients. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines.

RESULTS

Our search resulted in 34 articles. Most studies showed low-molecular-weight heparin (LMWH) is similar to unfractionated heparin (UFH) for VTE prevention; however, LMWH was more commonly used. Adjusted chemoprophylaxis dosing did not change the VTE rate but the timing did. Direct oral anticoagulants (DOACs) have been shown to be safe and effective in trauma and traumatic brain injury (TBI)/spinal cord injury (SCI). Studies showed VTE prophylaxis in EGS can be inconsistent and improves with guidelines that lower VTE events.

CONCLUSIONS

There may be no benefit to receiving LMWH over UFH in trauma patients. In addition, different drugs under the class of LMWH do not change the incidence of VTE. Adjusted dosing of enoxaparin does not seem to affect VTE incidence. The use of DOACs in the trauma TBI and SCI setting has been shown to be safe and effective in reducing VTE. One important consideration with VTE prophylaxis may be the timing of prophylaxis initiation, specifically as it relates to TBI, with a higher likelihood of developing VTE as time progresses. EGS patients are at a high risk of VTE. Improved compliance with clinical guidelines in this population is correlated with decreased thrombotic events.

The effectiveness and safety of LMWH for preventing thrombosis in patients with spinal cord injury: a meta-analysis

BACKGROUND

Unfractionated heparin (UFH) and low molecular weight heparin (LMWH) are commonly used for preventing venous thrombosis of the lower extremity in patients with traumatic spinal cord injury. Although, LMWH is the most commonly used drug, it has yet to be established whether it is more effective and safer than UFH. Further, a comparison of the effectiveness of LMWH in preventing thrombosis at different locations and different degrees of spinal cord injury has also not been clearly defined.

MATERIALS AND METHODS

Cohort studies comparing the use of LMWH and UFH in the prevention of lower limb venous thrombosis in patients with spinal cord injury were identified using PubMed. The risk of bias and clinical relevance of the included studies were assessed using forest plots. The Newcastle-Ottawa quality assessment scale was used to evaluate the quality of the included studies. The main results of the study were analyzed using Review Manager 5.3.

RESULTS

A total of five studies were included in this meta-analysis. Four studies compared the effectiveness and safety of LMWH and UFH in preventing thrombosis in patients with spinal cord injury. No significant differences were found between the therapeutic effects of the two drugs, and the summary RR was 1.33 (95% CI 0.42-4.16; P = 0.63). There was also no significant difference in the risk of bleeding between the two medications, and the aggregate RR was 0.78 (95% CI 0.55-1.12; P = 0.18). When comparing the efficacy of LMWH in preventing thrombosis in different segments and different degrees of spinal cord injury, no significant differences were found.

CONCLUSIONS

The results of this analysis show that compared with UFH, LMWH has no obvious advantages in efficacy nor risk prevention, and there is no evident difference in the prevention of thrombosis for patients with injuries at different spinal cord segments.

Lower Mortality and Morbidity with Low-Molecular-Weight Heparin for Venous Thromboembolism Prophylaxis in Spine Trauma

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

The objective of this study was to evaluate outcomes between patients receiving LMWH versus UH in a retrospective cohort of patients with spine trauma.

SUMMARY OF BACKGROUND DATA

Although multiple clinical trials have been conducted, current guidelines do not have enough evidence to suggest low-molecular-weight heparin (LMWH) or unfractionated heparin (UH) for venous thromboembolism (VTE) prophylaxis in spine trauma.

METHODS

Patients with spine trauma in the Trauma Quality Improvement Program datasets were identified. Those who died, were transferred within 72 hours, were deemed to have a fatal injury, were discharged within 24 hours, suffered from polytrauma, or were missing data for VTE prophylaxis were excluded. A propensity score was created using age, sex, severity of injury, time to prophylaxis, presence of a cord injury, and altered mental status or hypotension upon arrival, and inverse probability weighted logistic regression modeling was used to evaluate mortality, venous thromboembolic, return to operating room, and total complication rates. E values were used to calculate the likelihood of unmeasured confounders.

RESULTS

Those receiving UH (n = 7172) were more severely injured (P < 0.0001), with higher rates of spinal cord injury (32.26% vs. 25.32%, P < 0.0001) and surgical stabilization (29.52% vs. 22.94%, P < 0.0001) compared to those receiving LMWH (n = 20,341). Patients receiving LMWH had lower mortality (odds ratio [OR]: 0.47; 95% CI: 0.42-0.53; P < 0.001; E = 3.68), total complication (OR: 0.92; 95% CI: 0.88-0.95; P < 0.001; E = 1.39), and VTE event (OR: 0.80; 95% CI: 0.72-0.88; P < 0.001; E = 1.81) rates than patients receiving UH. There were no differences in rates of unplanned return to the operating room (OR: 1.01; 95% CI: 0.80-1.27; P = 0.93; E = 1.11).

CONCLUSION

There is an association between lower mortality and receiving LMWH for VTE prophylaxis in patients with spine trauma. A large randomized clinical trial is necessary to confirm these findings.

LEVEL OF EVIDENCE

3.

Venous Thromboembolism Chemoprophylaxis Within 24 Hours of Surgery for Spinal Cord Injury: Is It Safe and Effective?

OBJECTIVE

Current guidelines recommend initiation of venous thromboembolism (VTE) chemoprophylaxis within 72 hours of spinal cord injury (SCI). This study investigated the safety and efficacy of chemoprophylaxis within 24 hours of surgery for SCI.

METHODS

A retrospective review of 97 consecutive patients who underwent surgery for acute traumatic SCI at a single level 1 trauma center from 2013-2018 was performed. VTE/postoperative bleeding rates during hospitalization, demographics, medical/surgical complications, drain output, length of stay, and disposition were obtained. Chi-square with odds ratios (ORs), 1-way analysis of variance, and logistic regression were performed to establish significant differences between groups.

RESULTS

Seventy-nine patients were included, 49 received chemoprophylaxis within 24 hours and 20 within 24-72 hours. Cohort characteristics included an average age of 51.8 years, 77.2% male, 62.0% cervical, and 35.4% thoracic SCIs. Using the American Spinal Injury Association Impairment Scale (AIS), 39.2% were AIS-A injuries, 19.0% AIS-B, 25.3% AIS-C, and 16.5% AIS-D. Unfractionated heparin was administered in 88.6% of patients and 11.4% received low molecular weight heparin. Chemoprophylaxis within 24 hours of surgery was associated with a lower rate of VTE (6.1% vs. 35.0%; OR, 0.121; 95% confidence interval [CI], 0.027-0.535) and deep vein thrombosis (4.1% vs. 30.0%; OR, 0.099; 95% CI, 0.018-0.548) versus 24-72 hours. Pulmonary embolism rates were not significantly different (6.1% vs. 5.0%, p = 1.0). There were no postoperative bleeding complications and no significant difference in drain output between cohorts.

CONCLUSION

Early VTE chemoprophylaxis is effective with lower VTE rates when initiated within 24 hours of surgery for SCI and is safe with no observed postoperative bleeding complications.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on the Evaluation and Treatment of Patients With Thoracolumbar Spine Trauma: Prophylaxis and Treatment of Thromboembolic Events

QUESTION 1

Does routine screening for deep venous thrombosis prevent pulmonary embolism (or venous thromboembolism (VTE)-associated morbidity and mortality) in patients with thoracic and lumbar fractures?

RECOMMENDATION 1

There is insufficient evidence to recommend for or against routine screening for deep venous thrombosis in preventing pulmonary embolism (or VTE-associated morbidity and mortality) in patients with thoracic and lumbar fractures. Strength of Recommendation: Grade Insufficient.

QUESTION 2

For patients with thoracic and lumbar fractures, is one regimen of VTE prophylaxis superior to others with respect to prevention of pulmonary embolism (or VTE-associated morbidity and mortality)?

RECOMMENDATION 2

There is insufficient evidence to recommend a specific regimen of VTE prophylaxis to prevent pulmonary embolism (or VTE-associated morbidity and mortality) in patients with thoracic and lumbar fractures. Strength of Recommendation: Grade Insufficient.

QUESTION 3

Is there a specific treatment regimen for documented VTE that provides fewer complications than other treatments in patients with thoracic and lumbar fractures?

RECOMMENDATION 3

There is insufficient evidence to recommend for or against a specific treatment regimen for documented VTE that would provide fewer complications than other treatments in patients with thoracic and lumbar fractures. Strength of Recommendation: Grade Insufficient.

RECOMMENDATION 4

Based on published data from pooled (cervical and thoracolumbar) spinal cord injury populations, the use of thromboprophylaxis is recommended to reduce the risk of VTE events in patients with thoracic and lumbar fractures. Consensus Statement by the Workgroup The full version of the guideline can be reviewed at: https://www.cns.org/guideline-chapters/congress-neurological-surgeons-systematic-review-evidence-based-guidelines/chapter_7.

A Review of Two Heparin Prophylaxes for Trauma

Venous thromboembolism (VTE) prophylaxis has a significant impact on mortality and morbidity in trauma patients. This article reviews 9 published studies that investigate and compare low-dose unfractionated heparin (LDUH) with low-molecular-weight heparin (LMWH) for prophylaxis of VTE in the trauma patient population in terms of efficacy, safety, and cost. There is no difference between LDUH and LMWH for VTE prophylaxis. Four databases were utilized to find 9 relevant studies whose patient population was adult trauma patients: PubMed, CINAHL, EMBASE and Scopus. Two studies found statistically significant differences in deep venous thrombosis, and 3 found differences in pulmonary embolism between LDUH and LMWH. Only 1 study demonstrated a significant difference in bleeding complications between the 2 treatment regimens. Two statedthat using LDUH resulted in remarkable cost savings versus LMWH. The 9 studies all came to different conclusions. Contrary findings may have been affected by population variety, different dosing regimens, various applications of mechanical VTE prophylaxis, and/or different VTE-screening tools. All of the studies had major variances leading to conflicting results, which made this review unable to draw concrete conclusions. Limitations of each study, population variety, and disparity of dosing regimens made it difficult for this review to make recommendations for practice.

Thromboembolic Events After Traumatic Vertebral Fractures: An Analysis of 190,192 Patients

STUDY DESIGN

Retrospective cohort study OBJECTIVE.: To determine the rate of venous thromboembolism event (VTE) and risk factors for their occurrence in patients with vertebral fractures.

SUMMARY OF BACKGROUND DATA

Deep vein thrombosis or pulmonary embolism (VTE) events are a significant source of potentially preventable morbidity and mortality in trauma patients. In patients with traumatic vertebral fractures, a common high-energy injury sometimes resulting in spinal cord injury, there is debate about what factors may be associated with such VTEs.

METHODS

All patients with vertebral fractures in the American College of Surgeons National Trauma Data Bank Research Data Set (NTDB RDS) from years 2011 and 2012 were identified. Multivariate logistic regression was used to determine factors associated with the occurrence of VTE while considering patient factors, injury characteristics, and hospital course.

RESULTS

A total of 190,192 vertebral fractures patients were identified. The overall rate of VTE was 2.5%. In multivariate analysis, longer inpatient length of stay was most associated with increased VTEs with an odds ratio (OR) of up to 96.60 (95% CI: 77.67 - 129.13) for length of stay longer than 28 days (compared to 0 - 3 days). Additional risk factors in order of decreasing odds ratios were older age (OR of up to 1.65 [95% CI: 1.45 - 1.87] for patients age 70 - 79 years [compared to age 18 - 29 years]), complete spinal cord injuries (OR: 1.49 [95% CI: 1.31 - 1.68]), cancer (OR: 1.37 [95% CI: 1.25 - 1.50]), and obesity (OR: 1.32 [95% CI: 1.18 - 1.48]). Multiple associated non-spinal injuries were also associated with increased rates of VTE.

CONCLUSION

While the overall rate of VTE is relatively low after vertebral fractures, longer LOS and other defined factors to lesser extents were predisposing factors. By determining patients at greatest risk, protocols to prevent such adverse outcomes can be developed and optimized.

LEVEL OF EVIDENCE

3.

Meta-analysis of heparin therapy for preventing venous thromboembolism in acute spinal cord injury

OBJECTIVE

Venous thromboembolism (VTE) is a frequent complication in patients with acute spinal cord injury (SCI) and may have serious consequences. This study aimed to assess the efficacy and safety of heparin and low-molecular-weight heparin (LMWH) venous thromboprophylaxis in patients with acute SCI.

METHODS

PubMed, Web of Science, EMBASE and the Cochrane library were searched from January 1980 to August 2016. The primary outcome was the incidence of VTE. Secondary outcomes included the incidences of Deep-vein thrombosis (DVT), pulmonary embolism (PE) and major bleeding.

RESULTS

A total of 11 studies including 1605 patients qualified for inclusion. Four studies evaluated the efficacy of heparin treatment compared with placebo or no treatment. There were significant differences between the two treatments, and the summary RR was 0.35 (95% confidence interval (CI) 0.15-0.87; P = 0.02). Seven studies compared low dose unfractionated heparin (LDUH) with LMWH. The incidence of VTE was not significantly different between the two treatments (RR 1.09, 95% CI 0.63-1.89; P = 0.76). There were no differences in the incidence of major bleeding with unfractionated heparin versus LMWH (summary RR 1.32, 95% CI 0.62-2.84; P = 0.47).

CONCLUSIONS

In this meta-analysis, heparin exhibited protective effects compared with placebo or no treatment with respect to the occurrence of VTE; there were no differences between LMWH and unfractionated heparin with ret to thromboembolism prophylaxis efficacy. LMWH did not reduce the risk of bleeding compared with LDUH.

Prophylaxis of Venous Thrombosis in Neurocritical Care Patients: An Evidence-Based Guideline: A Statement for Healthcare Professionals from the Neurocritical Care Society

The risk of death from venous thromboembolism (VTE) is high in intensive care unit patients with neurological diagnoses. This is due to an increased risk of venous stasis secondary to paralysis as well as an increased prevalence of underlying pathologies that cause endothelial activation and create an increased risk of embolus formation. In many of these diseases, there is an associated risk from bleeding because of standard VTE prophylaxis. There is a paucity of prospective studies examining different VTE prophylaxis strategies in the neurologically ill. The lack of a solid evidentiary base has posed challenges for the establishment of consistent and evidence-based clinical practice standards. In response to this need for guidance, the Neurocritical Care Society set out to develop and evidence-based guideline using GRADE to safely reduce VTE and its associated complications.

Dalteparin versus Enoxaparin for the prevention of venous thromboembolic events in trauma patients

BACKGROUND

The use of low-molecular-weight heparin (LMWH) for the chemoprophylaxis of venous thromboembolism (VTE) in trauma patients is supported by Level-1 evidence. Because Enoxaparin was the agent used in the majority of studies for establishing the efficacy of LMWH in VTE, it remains unclear if Dalteparin provides an equivalent effect.

OBJECTIVE

To compare Dalteparin to Enoxaparin and investigate their equivalence as VTE prophylaxis in trauma.

PATIENTS/SETTING

Trauma patients receiving VTE chemoprophylaxis in the Surgical Intensive Care Unit of a Level-1 Trauma Center from 2009 (Enoxaparin) to 2010 (Dalteparin) were included.

MEASUREMENTS

The primary outcome was the incidence of clinically significant VTE. Secondary outcomes included heparin-induced thrombocytopenia (HIT), major bleeding, and drug acquisition cost savings. Equivalence margins were set between -5 and 5 %.

MAIN RESULTS

A total of 610 patient records (277 Enoxaparin, 333 Dalteparin) were reviewed. The two study groups did not differ significantly: blunt trauma 67 vs. 62 %, p = 0.27; mean Injury Severity Score (ISS) 17 ± 10 vs. 16 ± 10, p = 0.34; Acute Physiology and Chronic Health Evaluation (APACHE) II score 17 ± 9 vs. 17 ± 10, p = 0.76; time to first dose of LMWH 69 ± 98 vs. 65 ± 67 h, p = 0.57). The rates of deep venous thrombosis (DVT) (3.2 vs. 3.3 %, p = 1.00), pulmonary emboli (PE) (1.8 vs. 1.2 %, p = 0.74), and overall VTE (5.1 vs. 4.5 %, p = 0.85) did not differ. The absolute difference in the incidence of overall VTE was 0.5 % [95 % confidence interval (CI): -2.9, 4.0 %, p = 0.85]. The 95 % CI was within the predefined equivalence margins. There were no significant differences in the frequency of HIT or major bleeding. The total year-on-year cost savings, achieved with 277 patients during the switch to Dalteparin, was estimated to be $107,778.

CONCLUSIONS

Dalteparin is equivalent to Enoxaparin in terms of VTE in trauma patients and can be safely used in this population, with no increase in complications and significant cost savings.

Heparin for venous thromboembolism prophylaxis in patients with acute spinal cord injury: a systematic review and meta-analysis

OBJECTIVE

The objective of this study is to systematically review and estimate the effect of heparin for thromboprophylaxis in patients with acute spinal cord injury (SCI).

METHODS

We searched the PubMed database up to February 2013. Only randomized control trials (RCTs), quasi-RCTs, cohorts, case-control and cross-sectional studies were included. The incidence of venous thromboembolism (VTE) and major bleeding complication were recorded as the endpoints. The summary relative risks (RR) were calculated by meta-analysis.

RESULTS

A total of 18 studies with 2578 patients were included. Four studies evaluated the effects of low-dose unfractionated heparin (LDUH) compared placebo or untreated. No significant differences were observed, with the summary RR 0.661 (95% confidence interval (CI) 0.365-1.199; Z=1.36, P=0.173) for VTE. Only one RCT compared fixed-dose LDUH with adjusted-dose LDUH, which showed lower VTE incidence but higher bleeding incidence for adjusted dose. Nine trials have compared LDUH with low-molecular-weight heparin (LMWH). No significant differences were observed for VTE with the summary RR 1.633 (95% CI 0.822-3.243; Z=1.40, P=0.162). But major bleeding was lower with LMWH (summary RR=2.034, 95% CI 1.018-4.063; Z=2.01, P=0.044). Three studies compared different LMWHs, which included one for enoxaparin versus tinzaparin and two for enoxaparin versus dalteparin. No significant differences were observed with the summary RR 0.694 (95% CI 0.336-1.434; Z=0.99, P=0.324) for VTE. Three studies compared different dose of LMWH. No differences were observed.

CONCLUSION

Our meta-analysis showed that in patients with acute SCI, LDUH have no thromboprophylaxis effect compared with placebo or untreated; LMWH seems only can reduce bleeding incidence, but not prophylaxis thromboembolism compared with LDUH. Because of no good quality studies existed in this setting, well-designed RCTs are urgently needed.

Treatment of acute transverse myelitis and its early complications

Acute transverse myelitis (ATM) has many potential etiologies, but a significant proportion of cases are categorized as idiopathic despite thorough evaluation. Clinical presentation of ATM typically includes some combination of motor weakness, sensory symptoms, and bowel and bladder dysfunction. Prompt recognition, even before a final etiologic diagnosis is reached, is critical to initiating early therapeutic intervention to reduce the harmful effects of inflammation. Acute therapeutic options for ATM include corticosteroids, plasma exchange, IV immunoglobulin, and chemotherapeutic agents such as cyclophosphamide. In some instances, combinations of these therapies are used. This article examines the therapeutic approach to ATM and its various acute clinical manifestations.

Incidence and diagnosis of heparin-induced thrombocytopenia (HIT) in patients with traumatic injuries treated with unfractioned or low-molecular-weight heparin: a literature review

INTRODUCTION

The incidence of thromboembolic complications after major traumatic injuries is high (>50%). Thromboprophylaxis, often by low-molecular-weight heparin (LMWH) or unfractioned heparin (UH) is therefore routinely administered. Thromboprophylaxis is also advised after immobilisation for isolated lower leg injuries. Heparin induced thrombocytopenia (HIT) is a rare but very serious immune mediated complication of treatment with LMWH, which can cause potentially fatal thromboembolism. In the general medical and surgical population the incidence of HIT is 0.2%. Little is known about the incidence of HIT and value of screening in trauma patients and in isolated lower extremity injuries. Therefore, we performed a systematic literature review.

METHODS

The online databases Medline and EMBASE were searched independently by two authors. Manuscripts were selected for analysis by quantitative and qualitative selection. After eliminating duplicate articles and irrelevant studies, seven relevant papers reporting on the incidence of HIT in trauma patients were identified and two studies reported the incidence of HIT in patients with lower leg injuries.

RESULTS

The selected papers varied in study design: three randomised controlled trials, three cohort studies and one case report were identified. The methodological quality of the studies varied. In a total population of 1920 patients, HIT was identified in seven patients (0.36%). Pooling of data was impossible due to heterogeneity in study design and populations. No HIT was reported in 826 patients with lower extremity injuries, requiring immobilisation.

DISCUSSION

Only a few studies have reported on the incidence of HIT in trauma patients who receive prophylactic LMWH. In the heterogenous populations of the available studies, the incidence of HIT appears to be very low and comparable to other patient populations. There is hardly any literature on the incidence of HIT in patients with isolated lower leg injuries receiving LMWH, but incidence seems to be very low.

CONCLUSION

The incidence of HIT in trauma patients who receive LMWH thromboprophylaxis appears to be low (0.36%). Incidence of HIT in patients with isolated lower leg injuries receiving LMWH seems very low. Monitoring of platelet count could be considered in hospitalised patients with a high risk for development of HIT. A pre-test scoring system may identify these patients.

Silent pulmonary embolism in a patient with acute myocardial infarction and type B acute aortic dissection - a case report

A 69-year-old man while being treated for type B aortic dissection was also found to have acute myocardial infarction. The patient initially was treated conservatively. Prophylactic anticoagulant treatment of potential thrombosis was not given because of aortic dissection. Stent-graft implantation to the thoracic aorta was considered at the time. Unexpectedly, elective computer tomography (CT), revealed 2 large thrombi at the bifurcation of the pulmonary trunk. The patient did not show any symptoms of pulmonary embolism. Heparin therapy was initiated immediately. The patient responded well to the therapy and on transesophageal echocardiography and subsequent CT no embolic material was found. Since that time, the patient is receiving oral anticoagulation. The case we present raises the question of anticoagulation prophylaxis in the presence of aortic dissection in bedridden patients. Failure to use such therapy in our patient could have resulted in an unfavorable clinical outcome.

Risk factors for failure of heparin thromboprophylaxis in patients with acute traumatic spinal cord injury

Venous thromboembolism (VTE) is a well-recognized complication of Acute Traumatic Spinal Cord Injury (ATSCI). Despite prophylaxis by heparins, VTE occurs in a substantial number of ATSCI patients without an obvious explanation. In this matched case-control study we examined whether thrombophilia and other risk factors are associated with failure of thromboprophylaxis. Cases and controls receiving heparin thromboprophylaxis were selected from consecutively admitted ATSCI patients. Patients who developed a new, objectively confirmed, symptomatic VTE despite prophylaxis at hospital were matched by gender, age, level and mechanism of ATSCI with 2-3 controls without VTE. Patients were interviewed about VTE risk factors and tested for factor V Leiden (FVL), prothrombin G20210A (PT), methylenetetrahydrofolate reductase C677T homozygosity (MTHFR), lupus anticoagulant, homocysteine (Hcy) and plasma factor VIII (FVIII) levels. Twenty-two patients with new VTE episodes and 64 controls were ascertained. The total number of gene alterations for MTHFR, FVL and PT or elevated levels of Hcy or FVIII was significantly more common in patients compared to controls (82% vs. 48%, p=0.006). Multiple logistic regression proved the PT mutation, a positive family history of thrombosis and elevated levels of either FVIII or Hcy to be predictors of thrombosis.

CONCLUSION

A positive family history of VTE, carriership of the prothrombin mutation and elevated FVIII or Hcy levels were significantly associated with failure to prevent VTE by heparin therapy following ATSCI. Testing for thrombophilia in patients with ATSCI and possibly a more intense thromboprophylactic regimen seem desirable but need to be verified by a prospective study.