Prevention of venous thromboembolism after injury: an evidence-based report--part II: analysis of risk factors and evaluation of the role of vena caval filters

Timing of venous thromboemboli in patients with acetabular and pelvic ring fractures

PURPOSE

To determine the timing of symptomatic venous thromboemboli (VTE) in patients sustaining a pelvic and/or acetabular fracture. Secondly, to evaluate for any factors that may influence this timing.

METHODS

A retrospective cohort of 47 patients with acetabular and/or pelvic ring injuries who developed VTEs at a single academic level I trauma center were identified from 2012 to 2018. The chronology of VTE diagnosis in relation to date of injury, initial surgery, final surgery, and date of discharge was evaluated. Patients who developed VTEs were then evaluated based on known risk factors for VTE to determine if any of these affected timing.

RESULTS

Symptomatic VTEs were diagnosed in 3.8% of patients with pelvic and/or acetabular fractures. In patients who developed a thromboembolism, diagnosis occurred on average 21.5 (± 19.2), 20.7 (± 19.9), 9.8 (± 23.4), and 4.3 (± 27.6) days after injury, index procedure, final procedure, and date of discharge. 25% of patients developed VTE more than 4 weeks after their initial injury. No known risk factors effected the timing of VTE.

CONCLUSION

The 2015 OTA expert panel recommends 4 weeks of anticoagulation for orthopedic trauma patients at high risk of VTE, which may be too short a duration. In our cohort, 25% of VTEs occurred greater than 4 weeks after injury. Additional research is needed to clarify the exact duration of anticoagulation after pelvic and acetabular fractures; however, surgeons may want to consider anticoagulating patients for greater than 4 weeks.

LEVEL OF EVIDENCE

Level III-retrospective cohort.

Low-Molecular Weight Heparin is Superior to Unfractionated Heparin for Elderly Trauma Patients

BACKGROUND

Several studies have demonstrated that low-molecular weight heparin (LMWH) is superior to unfractionated heparin (UFH) in trauma patients. The superiority of either one has not been established for the elderly. In this study, we compared LMWH to UFH in elderly trauma patients.

METHODS

A retrospective analysis of the American College of Surgeons' Trauma Quality Improvement Program database was performed for patients aged ≥65 y. Propensity score matching was performed to minimize confounders between the two groups. Outcomes included venous thromboembolic (VTE) and bleeding events.

RESULTS

Overall, 93,987 patients were identified (mean age 77.1 ± 7.3 y, females 55,035 [58.6%]), of which 67,738 (72.1%) patients received LMWH and 26,249 (27.9%) received UFH. After Propensity score matching, LMWH was associated with a lower incidence of deep venous thrombosis (1.7% versus 2.1%, P = 0.007) and pulmonary embolisms (0.6% versus 1%, P< 0.001). LMWH was also associated with fewer bleeding complications (transfusions: 2.8% versus 3.5%, P< 0.001, procedures: 0.7% versus 0.9%, P = 0.007). Sub-analyses showed that differences in VTE rates were identified in patients with mild injuries (Injury Severity Score [ISS] <16, 0.6% versus 1.9%, P< 0.001). Differences in bleeding complications were identified in patients with injuries of mild (ISS <16, transfusions: 3% versus 3.8%, P< 0.001, surgeries: 0.3% versus 0.4%, P= 0.015) and moderate severity (ISS 16-24, transfusions: 1.9% versus 2.7%, P= 0.038, surgeries: 1% versus 1.7%, P= 0.013).

CONCLUSION

LMWH prophylaxis is superior to UFH for VTE prevention among elderly trauma patients. LMWH prophylaxis is associated with fewer bleeding complications compared to UFH in patients with injuries of mild or moderate severity.

Incidence and Nature of Lower-Limb Deep Vein Thrombosis in Patients with Polytrauma on Thromboprophylaxis: A Prospective Cohort Study

Purpose

Deep vein thrombosis (DVT) is common among the severely injured and may lead to pulmonary embolism (PE), which can be life threatening. Thromboprophylaxis may reduce the incidence of venous thromboembolism (VTE); it does not guarantee complete protection. This study’s primary aim was to determine the incidence and nature of lower-limb DVT in polytrauma patients taking prophylaxis. The secondary objective was to assess the incidence of DVT-related complications, including the development of PE and death.

Patients and Methods

This prospective observational study included patients age 18 years or older who presented with polytrauma directly from the scene and were admitted into the trauma unit between March 1, 2020 and August 31, 2020. All patients underwent lower-limb ultrasound during their hospital course to diagnose DVT.

Results

A total of 169 patients underwent extremity Doppler ultrasound to detect DVT. Of these, 69 patients (40.8%) were considered at the highest-risk for VTE development. For VTE prophylaxis, 115 patients (68%) received pharmacologic agents, and 54 patients (32%) had intermittent pneumatic compression on admission. Three patients (1.8%) developed DVT despite prophylaxis. Four patients (2.4%) developed PE during the index presentation and were diagnosed between days 3 and 13 after injury. Early DVT was not detected in any patients with diagnosed PE. Overall, nine patients (5.33%) died, but no in-hospital deaths were related to DVT and/or PE.

Conclusion

The incidence of DVT in polytrauma patients remains low in our small series, perhaps because of the mandatory VTE risk assessment for all hospitalized patients and the early initiation of prophylaxis. Using a trauma center registry to measure DVT and PE incidence regularly is recommended to improve trauma care quality.

Risk factors of postoperative deep vein thrombosis (DVT) under low molecular weight heparin (LMWH) prophylaxis in patients with thoracolumbar fractures caused by high-energy injuries

To determine the incidence of DVT and to evaluate the risk factors of DVT under LMWH prophylaxis in patients with thoracolumbar fractures caused by high‑energy injuries postoperatively. A total of 534 patients from January 2016 to November 2019 were included in this retrospective study. Medical record data, including demographic data, perioperative variables, and laboratory results, were collected. LMWH prophylaxis was used for DVT in all the patients. The incidence and risk factors of DVT after surgery were identified by logistic regression analysis and receiver operating characteristic (ROC) curve analysis. The overall incidence of postoperative DVT was 18.91% (101/534). Three patients (0.56%) had proximal DVT and ninety-eight (18.35%) patients had distal DVT. The incidence of postoperative DVT in patients with thoracic fractures was 26.80% and 15.50% with lumbar fractures. The multivariate analysis showed that six risk factors increased the incidence of postoperative DVT, including advanced age, decreased lower extremity motor, blood transfusion, duration of bed rests, fibrinogen (FIB), and D-dimer. The ROC analysis indicated that the diagnostic value of D-dimer was highest whose area under the ROC curves (AUC) value was 0.754. Despite LMWH prophylaxis, the risk of postoperative DVT is still very high, especially in thoracic fracture. Advanced age, decreased lower extremity motor, blood transfusion, duration of bed rests, FIB, and D-dimer are risk factors for DVT. Moreover, the diagnostic value of D-dimer is the highest among these factors.

Prophylactic inferior vena cava filters for operative pelvic fractures: a twelve year experience

INTRODUCTION

Conflicting evidence exists regarding the role of inferior vena cava filters (IVCFs) in the prevention of pulmonary embolism. The aim of this study was to review an institutional policy of prophylactic IVCF placement in all operative pelvic and acetabular fractures as a means of preventing PE by comparing it to a historical prepolicy period of significantly less aggressive IVCF placement.

METHODS

The trauma registry of a single level 1 trauma center was retrospectively queried for all pelvic or acetabular fractures for the prepolicy and intervention periods as defined as January 2003-December 2008 and January 2009-December 2014, respectively-yielding 231 patients for analysis. The primary and secondary outcomes measured were the incidence of PE and deep vein thrombosis.

RESULTS

The rate of prophylactic IVCF insertion significantly increased during the study period (p < 0.001). The incidence of pulmonary embolism (1.8% vs. 5.1%, p = 0.351) and DVT (19.3% vs. 10.3%, p = 0.231) were not significantly different when comparing the prepolicy and intervention cohorts. In patients with operative fractures, a nonsignificant trend of increasing incidence of DVTs was appreciated in patients with a prophylactic IVCF versus those without prophylactic IVCF (13 vs. 2, p = 0.222).

DISCUSSION

A policy of increased use of prophylactic IVCFs in patients with operative pelvic and acetabular fractures failed to reduce the incidence of PE or DVT. In contrast, several case reports and institutional series have published several risks associated with IVCF placement including failure to retrieve temporary IVCF.

CONCLUSION

The benefit of prophylactic IVCF in this patient population is unclear.

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.

Venous thromboembolism events following spinal fractures: A single center experience

OBJECTIVE

Venous thromboembolic events (VTE), including deep venous thrombosis (DVT) and pulmonary embolism (PE), are a major cause of readmission, morbidity, and mortality after spine surgery. Patients with spinal fractures are particularly at an increased risk for VTE. The objective of this study is to understand VTE risk factors in this patient population and to examine current institutional practices.

PATIENTS AND METHODS

We retrospectively examined records from 195 consecutive patients with spinal fractures who underwent spinal stabilization surgeries- amongst a cohort of 6869 patients who underwent spinal surgery. We collected data on patient demographics, surgery, hospital course, and 30-day rates of VTE, readmission, reoperation. Multivariable logistic regression was used to identify independent predictors of each outcome.

RESULTS

Among 195 patients undergoing surgery for spinal fractures, 9.2% experienced a VTE, compared to 2.3% among all other spine patients (OR 4.466, p < 0.0001). 48.7% spine fracture patients received chemoprophylactic anticoagulation, compared to 35.7% of all other spine patients (OR 2.657, p < 0.0001). Within 30 days of surgery, estimated blood loss (EBL) was associated with VTE (OR 1.001, p = 0.0415) and DVT (OR 1.001, p = 0.049), and comorbid cardiac disease burden showed a trend toward significance in predicting both VTE (OR 1.890, p = 0.0956) and DVT (OR 4.228, p = 0.0549). Number of levels in surgery predicted PE within 30 days of surgery (OR 1.573, p = 0.0107).

CONCLUSIONS

Compared to all other patients undergoing spine surgery, patients with spinal fractures are more likely to receive chemoprophylactic anticoagulation, but nevertheless have a higher rate of VTE events. EBL and comorbid disease burden predict VTE events in patients with spine fractures.

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.

Inferior Vena Cava Filters: Current Indications, Techniques, and Recommendations

The vena cava filter (VCF) is intended to prevent the progression of deep venous thrombosis to pulmonary embolism. Recently, the indications for VCF placement have expanded, likely due in part to newer retrievable inferior vena caval filters and minimally invasive techniques. This article reviews the available VCFs, the indications for use, the techniques for placement, and possible outcomes and complications.

High level of venous thromboembolism in critically ill trauma patients despite early and well-driven thromboprophylaxis protocol

Background

Venous thromboembolism (VTE) is one of the most common preventable causes of in-hospital death in trauma patients surviving their injuries. We assessed the prevalence, incidence and risk factors for deep venous thrombosis (DVT) and pulmonary embolism (PE) in critically ill trauma patients, in the setting of a mature and early mechanical and pharmacological thromboprophylaxis protocol.

Methods

This was a prospective observational study on a cohort of patients from a surgical intensive care unit of a university level 1 trauma centre. We enrolled consecutive primary trauma patients expected to be in intensive care for ≥48 h. Thromboprophylaxis was protocol driven. DVT screening was performed by duplex ultrasound of upper and lower extremities within the first 48 h, between 5 and 7 days and then weekly until discharge. We recorded VTE risk factors at baseline and on each examination day. Independent risk factors were analysed using a multivariate logistic regression.

Results

In 153 patients with a mean Injury Severity Score of 23 ± 12, the prevalence of VTE was 30.7%, 95 CI [23.7–38.8] (29.4% DVT and 4.6% PE). The incidence was 18%, 95 CI [14–24] patients-week. The median time of apparition of DVT was 6 days [1; 4]. The global protocol compliance was 77.8% with a median time of introduction of the pharmacological prophylaxis of 1 day [1; 2]. We identified four independent risk factors for VTE: central venous catheter (OR 4.39, 95 CI [1.1–29]), medullar injury (OR 5.59, 95 CI [1.7–12.9]), initial systolic arterial pressure <80 mmHg (OR 3.64, 95 CI [1.3–10.8]), and pelvic fracture (OR 3.04, 95 CI [1.2–7.9]).

Conclusion

Despite a rigorous, protocol-driven thromboprophylaxis, critically ill trauma patients showed a high incidence of VTE. Further research is needed to tailor pharmacological prophylaxis and balance the risks and benefits.

Electronic supplementary material

The online version of this article (doi:10.1186/s13613-017-0315-0) contains supplementary material, which is available to authorized users.

Unfractionated heparin versus low-molecular-weight heparin for venous thromboembolism prophylaxis in trauma

BACKGROUND

Venous thromboembolism (VTE) is a common complication in trauma patients. Pharmacologic prophylaxis is utilized in trauma patients to reduce their risk of a VTE event. The Eastern Association for the Surgery of Trauma guidelines recommend use of low-molecular-weight heparin (LMWH) as the preferred agent in these patients. However, there is literature suggesting that unfractionated heparin (UFH) is an acceptable, and less costly, alternative VTE prophylaxis agent with equivalent efficacy in trauma patients. We examined data from the Michigan Trauma Quality Improvement Program to perform a comparative effectiveness study of UFH versus LMWH on outcomes for trauma patients.

METHODS

We conducted an analysis of the Michigan Trauma Quality Improvement Program data from January 2012 to December 2014. The data set contains information on date, time, and drug type of the first dose of VTE prophylaxis. Thirty-seven thousand eight hundred sixty-eight patients from 23 hospitals were present with an Injury Severity Score of 5 or greater and hospitalization for more than 24 hours. Patients were excluded if they died within 24 hours or received no pharmacologic VTE prophylaxis or agents other than UFH or LMWH while admitted to the hospital. We compared patients receiving LMWH to those receiving UFH. Outcomes assessed were VTE event, pulmonary embolism, deep vein thrombosis, and mortality during hospitalization. We used a generalized estimating equation approach to fit population-averaged logistic regression models with the type of first dose of VTE prophylaxis as the independent variable. Unfractionated heparin was considered the reference value. Timing of the first dose of VTE prophylaxis was entered into the model in addition to standard covariates. Odds ratios were generated for each of the dependent variables of interest.

RESULTS

The analysis cohort consisted of 18,010 patients. Patients administered LMWH had a decreased risk of mortality (odds ratio, 0.64; confidence interval, 0.49-0.83), VTE (odds ratio, 0.67; confidence interval, 0.53-0.84), pulmonary embolism (odds ratio, 0.53; confidence interval, 0.35-0.79), and deep vein thrombosis (odds ratio, 0.73; confidence interval, 0.57-0.95) when compared with UFH following risk adjustment and accounting for hospital effect. The reduced risk of a VTE event for patients receiving LMWH was most pronounced for patients in the lower injury-severity categories.

CONCLUSIONS

In our examination of VTE prophylaxis drug effectiveness, LMWH was found to be superior to UFH in reducing the incidence of mortality and VTE events among trauma patients. Therefore, LMWH should be the preferred VTE prophylaxis agent for use in hospitalized trauma patients.

LEVEL OF EVIDENCE

Therapeutic, level III.

The high-risk polytrauma patient and inferior vena cava filter use

OBJECTIVES

The aim of this study was to assess the impact on practice of vena cava filter insertion guidelines (Eastern Association for the Surgery of Trauma: practice management guidelines).

DESIGN

The study was performed at a level 1 trauma centre with data from the 'Trauma Audit and Research Network' cross-referenced to hospital data.

RESULTS

A total of 1138 specific 'high-risk' major trauma patients were identified over a 6-year period. The mean age was 46 years (18-102) and the male to female ratio was 3.3:1. The average Injury Severity Score was 23.6 (4-75). The overall DVT rate was 2.6% and the PE rate was 1.8%. A retrievable IVC filter was inserted in 42 cases (3.8%). The filter retrieval rate was 23.8% at a mean of 68.5days (4-107). Only one complication was reported of a breakthrough PE despite filter. Applying the EAST guidelines to this cohort would have suggested filter insertion in 279 (24.6%) cases. The kappa concordance value between observed practice and the 'EAST filter group' was 0.103 (poor). The PE rate in the 'EAST filter group' was 2.2% vs 1.6% in the 'no filter group' (p=0.601, no statistical difference) and the observed odds ratio was 0.814 (95% CI 0.413, 1.602).

CONCLUSION

The EAST guidelines are useful but may be overestimating the need for filter insertion.

F11 rs2289252T and rs2036914C Polymorphisms Increase the Activity of Factor XI in Post-trauma Patients with Fractures Despite Thromboprophylaxis

OBJECTIVE

To evaluate the association between F11 rs2289252, rs2036914 polymorphisms and the activity of clotting factor XI in post-trauma patients with fractures receiving routine anticoagulation therapy for deep venous thrombosis (DVT).

METHODS

A case-control study involving 110 consecutive post-trauma patients with fractures and DVT in our hospital was conducted from April 2014 to October 2015; these patients comprised a DVT group. Another 40 sex- and age-matched patients with fractures but without DVT served as controls. Additionally, 40 sex- and age-matched healthy people were chosen as a normal group. Venous blood samples (2 mL) were drawn from all participants and genomic DNA extracted from the leukocytes of the patients with fracture-related DVT, whose genotype and allele frequency distribution of F11 gene rs2089252 and rs2036914 single nucleotide polymorphism were then assessed by a sequencing method. The activity of factor XI was measured by a solidification method in all participants, including those in control and normal groups.

RESULTS

The activity of factor XI in patients with fracture-related DVT and F11 rs2089252 CT was 1.16 times that of those with CC genotypes (P < 0.0001), whereas in patients with fracture-related DVT and F11 rs2089252 TT genotypes it was 1.32 times that of those with CC genotypes (P < 0.0001), in patients with fracture-related DVT and F11 rs2089252 T allele it was 1.24 times that of those with C allele (P < 0.05), in patients with fracture-related DVT and F11 rs2036914 CC it was 1.35 times that of those with TT genotypes, in patients with fracture-related DVT and F11 rs2036914 CT genotypes it was 1.12 times that of those with TT genotypes (P < 0.05), and in patients with fracture-related DVT F11 and rs2036914 C allele it was 1.22 times that of those with T allele (P < 0.05). The activity of factor XI was significantly higher in the control than in the normal group (P < 0.05).

CONCLUSIONS

High activity of factor XI indicates a risk of occurrence of DVT in post-trauma patients with fractures. F11 rs2089252 and rs2036914 (single nucleotide polymorphisms) are associated with activity of factors XI in such patients despite prophylaxis.

A simplified stratification system for venous thromboembolism risk in severely injured trauma patients

BACKGROUND

The objective of this study was to re-evaluate and simplify the Greenfield risk assessment profile (RAP) for venous thromboembolism (VTE) in trauma using information readily available at the bedside.

METHODS

Retrospective review of 1233 consecutive admissions to the trauma intensive care unit from August 2011-January 2015. Univariate analyses were performed to determine which RAP risk factors were significant contributors to VTE. Multivariable logistic regression was used to develop models for risk stratification. All results were considered statistically significant at P ≤ 0.05.

RESULTS

The study population was as follows: age 44 ± 19, 75% male, 72% blunt, injury severity score 21 ± 13, RAP score 9 ± 5, and 8% mortality. Groups were separated into +VTE (n = 104) and -VTE (n = 1129). They were similar in age, gender, mechanism, and mortality, but injury severity and RAP scores were higher in the +VTE group (all P < 0.0001). The +VTE group had more transfusions and longer time to prophylaxis (all P < 0.05). Receiving four or more transfusions in the first 24 h (odds ratio [OR], 2.60; 95% confidence interval [CI], 1.64-4.13), Glasgow coma score <8 for >4 h (OR, 2.13; 95% CI, 1.28-3.54), pelvic fracture (OR, 2.26; 95% CI, 1.44-3.57), age 40-59 y (OR, 1.70; 95% CI, 1.10-2.63), and >2-h operation (OR, 1.80; 95% CI, 1.14-2.85) predicted VTE with an area under the receiver operator curve of 0.729, which was comparable with 0.740 for the RAP score alone.

CONCLUSIONS

VTE risk in trauma can be easily assessed using only five risk factors, which are all readily available at the bedside (transfusion, Glasgow coma scale, pelvic fracture, prolonged operation, and age). This simplified model provides similar predictive ability to the more complicated RAP score. Prospective validation of a simplified risk assessment score is warranted.

Aspirin as added prophylaxis for deep vein thrombosis in trauma: A retrospective case-control study

BACKGROUND

Current prophylaxis does not completely prevent deep vein thrombosis (DVT) in trauma patients. Recent data suggest that platelets may be a major contributor to hypercoagulability after trauma, indicating a potential role for antiplatelet medications in prophylaxis for DVT. We sought to determine if preinjury aspirin use was associated with a reduced incidence of lower extremity DVT in trauma patients.

METHODS

Using a retrospective case-control design, we matched 110 cases of posttrauma lower extremity DVT one-to-one with controls using seven covariates: age, admission date, probability of death, number of DVT risk factors, sex, mechanism of injury, and presence of head injury. Data collected included 26 risk factors for DVT, prehospital medications, and in-hospital prophylaxis. Logistic regression models were created to examine the relationship between prehospital aspirin use and posttrauma DVT.

RESULTS

Preinjury aspirin was used by 7.3% of cases (patients diagnosed with in-hospital DVT) compared with 13.6% of controls (p = 0.1). Aspirin was associated with a significant protective effect in multivariate analysis, with an odds ratio of 0.17 (95% confidence interval, 0.04-0.68; p = 0.012) in the most complete model. When stratified by other antithrombotic use, aspirin showed a significant effect only when used in combination with heparinoid prophylaxis (odds ratio, 0.35; 95% confidence interval, 0.13-0.93; p = 0.036).

CONCLUSION

Preinjury aspirin use seems to significantly lower DVT rate following injury. This association is strongest when heparinoid prophylaxis is prescribed after patients on preinjury aspirin therapy are admitted. Aspirin as added prophylaxis for DVT in trauma patients needs to be further evaluated.

LEVEL OF EVIDENCE

Prognostic and epidemiologic study, level III.

Vena Caval Filters: A Review for Intensive Care Specialists

Venous thromboembolism (VTE) is a common complication among patients in the intensive care unit. While anticoagulation remains standard therapy, vena caval filters are an important alternative when anticoagulation is contraindicated. To determine the safety and efficacy of vena caval filters in the treatment of VTE, a comprehensive review of the English-language medical literature was performed. Except for one randomized controlled trial, the literature supporting the use of vena caval filters consists almost exclusively of case series, which in many instances are limited by incomplete and short follow-up. While case series suggest that filters function effectively in the prevention of pulmonary embolism (2%-4% symptomatic pulmonary embolism [PE], fatal PE < 2%), recent higher quality studies indicate that filters may not provide significant additional protection to that provided by anticoagulation alone. Furthermore, filters are associated with a 2- fold increase in the incidence of recurrent DVT. Until randomized comparative studies are available, the safety and efficacy of all the available devices should be considered to be roughly equivalent. Since filters do not inhibit continued clot formation, all filter patients should receive anticoagulation for durations appropriate for their thrombotic disorder. Although extended anticoagulation may prevent thrombotic complications associated with filter placement, this strategy has yet to be experimentally tested. While many additional indications for vena caval filter use have been proposed (VTE in cancer patients, PE prophylaxis in trauma patients, etc), well-designed clinical trials demonstrating their efficacy in these situations are lacking. Further development of temporary/retrievable filters, which offer the potential to avoid the long-term complications of permanent filters, should be a research priority. Until additional data are available, vena caval filters should generally be restricted to patients with VTE who cannot receive anticoagulation.

Optional Vena Cava Filters: What, Why, and When

Optional vena cava filters can used to provide either short-term or permanent protection from pulmonary embolism. These devices have recently become available for clinical use in the United States. However, there remains a paucity of data about these devices and their outcomes. This article reviews current and future devices, the rationale behind non-permanent caval filtration, and the generally accepted guidelines for their clinical application.

Methods and Guidelines for Venous Thromboembolism Prevention in Polytrauma Patients with Pelvic and Acetabular Fractures

Sequential compression devices and chemical prophylaxis are the standard venous thromboembolism (VTE) prevention for trauma patients with acetabular and pelvic fractures. Current chemical pharmacological contemplates the use of heparins or fondaparinux. Other anticoagulants include coumarins and aspirin, however these oral agents can be challenging to administer and may need monitoring. When contraindications to anticoagulation in high-risk patients are present, prophylactic inferior vena cava filters can be an option to prevent pulmonary emboli. Unfortunately strong evidence about the most effective method, and the timing of their commencement, in patients with pelvic and acetabular fractures remains controversial.

Changes in the rate of prophylactic vena cava filter insertion at a university hospital

OBJECTIVE

We previously demonstrated a high rate of prophylactic vena cava filter (VCF) insertion at our institution. We have since attempted to restrict the use of VCF to indications supported by Level-I evidence. This study was designed to evaluate the success of our interventions.

METHODS

All patients receiving VCF between 2007-2009 and 2012-2014 at a university hospital were reviewed. After assessing the use of VCF in the first period, a meeting was convened among the Departments of Radiology, Vascular Surgery and Trauma. Policy was implemented to avoid the inappropriate use of VCF. Data were prospectively collected in the second period to assess the effect of our intervention.

RESULTS

There were 156 VCF placed from 2012 to 2014. VCF was absolutely indicated in 84% of cases, relatively indicated in 9% and prophylactic in 7%. These data contrast our previous experience from 2007 to 2009. In the earlier series, a total of 244 filters were placed, in which 54% of patients had an absolute indication, 14% relative, and 32% prophylactic. There was a significant decrease in filters placed for pure prophylaxis: whereas 76 prophylactic filters were placed between 2007 and 2009, only 11 were placed between 2012 and 2014 (p < 0.0001). No significant differences existed for relatively indicated filters. The department of trauma and surgical critical care (TSCC) observed the most dramatic change in practice. TSCC placed 61 prophylactic VCF between 2007 and 2009 (57% of all filters placed by the department), and 4 prophylactic VCF from 2012 to 2014 (15% of filters placed by TSCC) (p < 0.0001).

CONCLUSION

These findings demonstrate a significant change in the attitudes regarding prophylactic VCF insertion between the two periods of study. Further investigations must be performed to assess changes in clinical outcomes that may result from the altered practice at our university.

Early pharmacological venous thromboembolism prophylaxis is safe after operative fixation of traumatic spine fractures

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To examine the impact of early (<48 hr) versus late (≥48 hr) initiation of pharmacological venous thromboembolism (VTE) prophylaxis on outcomes and complications among trauma patients undergoing operative fixation of spine fractures.

SUMMARY OF BACKGROUND DATA

VTE complications are associated with poor outcomes after trauma. Although pharmacological prophylaxis decreases the risk of VTE after trauma, concerns regarding bleeding-related complications among certain patient subgroups persist. At present, there are limited data regarding the safety of early VTE prophylaxis in trauma patients undergoing operative fixation of spine fractures.

METHODS

We performed a 5-year retrospective analysis of our level 1 trauma center registry to identify consecutive patients undergoing operative fixation of spine fractures. Demographics, injury patterns and severity, details of operative procedures, timing of administration of VTE prophylaxis, and outcomes were analyzed. Patients receiving early VTE prophylaxis were compared with patients receiving late VTE prophylaxis. Multivariate analysis was performed to identify independent predictors of VTE.

RESULTS

Of 1432 patients with spine fractures, 206 patients (14.4%) underwent operative fixation. Forty-eight (23.3%) received early VTE prophylaxis and 158 (76.7%) received late VTE prophylaxis. No patient developed an epidural hematoma or postoperative bleeding necessitating intervention in either group. Thirteen patients (6.2%) developed VTE, of which 12 occurred in the late VTE prophylaxis group. Age 45 years or more (odds ratio = 5.12, 95% confidence interval = 1.01-25.94, P = 0.048) and traumatic brain injury (odds ratio = 6.94, 95% confidence interval = 1.19-40.35, P = 0.031) were independently associated with an increased risk for VTE.

CONCLUSION

Pharmacological VTE prophylaxis initiated within 48 hours of operative fixation of traumatic spine fractures seems to be safe and is not associated with an increased risk of bleeding or neurological complications. Large, multicenter prospective studies are required to further define the efficacy and safety of an early pharmacological VTE prophylaxis strategy in this at-risk patient population.

LEVEL OF EVIDENCE

3.

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.

[Vena cava filter. Which indications remain in the era of differentiated anticoagulation?]

CLINICAL/METHODICAL ISSUE

Venous thromboembolism (VTE) is the third most common disease of the cardiovascular system. It is associated with a 30-day lethality in the range of 6  % in deep vein thrombosis and 12  % in pulmonary embolism (PE). There are various guidelines with sometimes controversial recommendations regarding the use of inferior vena cava (IVC) filters.

STANDARD RADIOLOGICAL METHODS

Implantation of IVC filters is a standard therapy in selected patients with an estimated 259,000 filters implanted in 2012.

METHODICAL INNOVATIONS

Optionally retrievable filters are increasingly being used in clinical routine practice. Future developments will include biodegradable and drug-eluting filters.

PERFORMANCE

When compared to anticoagulation as the reference therapy of VTE, IVC filters will significantly reduce the frequency of symptomatic PE; however, there is no advantage in overall survival for either therapy.

ACHIEVEMENTS

Despite different guidelines in clinical routine practice the use of IVC filters appears to depend on the individual clinical experience and assessment of the interventionalist.

PRACTICAL RECOMMENDATIONS

Nowadays retrievable filters should be used although there are relevant differences between the various devices. As a matter of principle all IVC filters should be removed as soon as adequate anticoagulation can be established.

Duodenal penetration of an inferior vena cava filter: case report and literature review

The insertion of inferior vena cava filters (IVCF) is a well-known therapy used in the prevention of pulmonary embolism (PE). The incidence of IVCF-related complications is low and complete caval penetration of a filter with adjacent organ injury has a reported incidence of 0–1%. We report the case of an 18-year-old male who sustained a spinal cord injury after a motor vehicle crash. The patient received a prophylactic IVCF and subsequently presented with right flank pain, postprandial nausea, and vomiting. His exam was benign and a computed tomography scan revealed extra-caval penetration of the filter with struts within the duodenal lumen and psoas muscle. The patient underwent an exploratory laparotomy with extraction of the filter, inferior vena cava venorrhaphy, and repair of the duodenal injury. This complication illustrates the potential morbidity of a common procedure and emphasizes the importance of investigating the IVCF as a possible source of abdominal pain.

Thromboprophylaxis for trauma patients

BACKGROUND

Trauma is a leading causes of death and disability in young people. Venous thromboembolism (VTE) is a principal cause of death. Trauma patients are at high risk of deep vein thrombosis (DVT). The incidence varies according to the method used to measure the DVT and the location of the thrombosis. Due to prolonged rest and coagulation abnormalities, trauma patients are at increased risk of thrombus formation. Thromboprohylaxis, either mechanical or pharmacological, may decrease mortality and morbidity in trauma patients who survive beyond the first day in hospital, by decreasing the risk of VTE in this population.A previous systematic review did not find evidence of effectiveness for either pharmacological or mechanical interventions. However, this systematic review was conducted 10 years ago and most of the included studies were of poor quality. Since then new trials have been conducted. Although current guidelines recommend the use of thromboprophylaxis in trauma patients, there has not been a comprehensive and updated systematic review since the one published.

OBJECTIVES

To assess the effects of thromboprophylaxis in trauma patients on mortality and incidence of deep vein thrombosis and pulmonary embolism. To compare the effects of different thromboprophylaxis interventions and their effects according to the type of trauma.

SEARCH METHODS

We searched The Cochrane Injuries Group Specialised Register (searched April 30 2009), Cochrane Central Register of Controlled Trials 2009, issue 2 (The Cochrane Library), MEDLINE (Ovid) 1950 to April (week 3) 2009, EMBASE (Ovid) 1980 to (week 17) April 2009, PubMed (searched 29 April 2009), ISI Web of Science: Science Citation Index Expanded (SCI-EXPANDED) (1970 to April 2009), ISI Web of Science: Conference Proceedings Citation Index-Science (CPCI-S) (1990 to April 2009).

SELECTION CRITERIA

Randomized controlled clinical trials involving people of any age with major trauma defined by one or more of the following criteria: physiological: penetrating or blunt trauma with more than two organs and unstable vital signs, anatomical: people with an Injury Severity Score (ISS) higher than 9, mechanism: people who are involved in a 'high energy' event with a risk for severe injury despite stable or normal vital signs. We excluded trials that only recruited outpatients, trials that recruited people with hip fractures only, or people with acute spinal injuries.

DATA COLLECTION AND ANALYSIS

Four authors, in pairs (LB and CM, EF and RC), independently examined the titles and the abstracts, extracted data, assessed the risk of bias of the trials and analysed the data. PP resolved any disagreement between the authors.

MAIN RESULTS

Sixteen studies were included (n=3005). Four trials compared the effect of any type (mechanical and/or pharmacological) of prophylaxis versus no prophylaxis. Prophylaxis reduced the risk of DVT in people with trauma (RR 0.52; 95% CI 0.32 to 0.84). Mechanical prophylaxis reduced the risk of DVT (RR = 0.43; 95% CI 0.25 to 0.73). Pharmacological prophylaxis was more effective than mechanical methods at reducing the risk of DVT (RR 0.48; 95% CI 0.25 to 0.95). LMWH appeared to reduce the risk of DVT compared to UH (RR 0.68; 95% CI 0.50 to 0.94). People who received both mechanical and pharmacological prophylaxis had a lower risk of DVT (RR 0.34; 95% CI 0.19 to 0.60)

AUTHORS' CONCLUSIONS

We did not find evidence that thromboprophylaxis reduces mortality or PE in any of the comparisons assessed. However, we found some evidence that thromboprophylaxis prevents DVT. Although the strength of the evidence was not high, taking into account existing information from other related conditions such as surgery, we recommend the use of any DVT prophylactic method for people with severe trauma.

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.

Venous thromboembolism in the elderly: the result of comorbid conditions or a consequence of injury?

BACKGROUND

Venous thromboembolism (VTE) is a common complication in trauma patients. Several risk factors have been identified that may place patients at in increased risk for VTE including preexisting medical conditions, iatrogenic factors, and injury-related factors. Advanced age has also been implicated as a risk factor for VTE. The purpose of this study was to determine the incidence and outcomes of VTE in geriatric trauma patients as well as to identify risk factors for VTE in this population.

METHODS

We performed a 10-year retrospective review of all trauma patients aged 65 years or older discharged with a diagnosis of VTE. Demographic data, injuries, mechanism, Injury Severity Score, Abbreviated Injury Score, Glasgow Coma Scale, length of stay, and mortality were collected.

RESULTS

: Of 2,521 trauma patients aged 65 years or older, 82 (3.2%) were diagnosed with VTE. Seventy-two of 82 patients were diagnosed with deep vein thrombosis, and pulmonary embolism was found in 8 patients. Two patients had both a deep vein thrombosis and pulmonary embolism. Independent predictors of VTE included traumatic brain injury (p < 0.05); chest Abbreviated Injury Score ≥ 3 (p < 0.001); mechanical ventilation (p < 0.001); major operation (p < 0.001); and history of VTE (p = 0.05). Other comorbid conditions were not significantly associated with VTE. Preinjury anticoagulation had a trend toward a protective effect. Although length of stay was longer in patients with VTE (adjusted mean difference 14.7 days, p < 0.001), mortality for patients with and without VTE was 8.5% and 7.0%, respectively (p = 0.59).

CONCLUSION

VTE is associated with prolonged length of stay and duration of mechanical ventilation as well as continued medical dependence after discharge. Several risk factors place the elderly trauma patient at an increased risk for VTE, and trauma or injury-related risk factors seem to have a greater impact on the development of VTE in comparison to underlying conditions or increasing patient age (>65 years).

LEVEL OF EVIDENCE

II, prognostic study.

Comprehensive assessment of prophylactic preoperative inferior vena cava filters for major spinal reconstruction in adults

STUDY DESIGN

A retrospective data analysis.

OBJECTIVE

To report a comprehensive assessment of preoperative prophylactic inferior vena cava (IVC) filter placement in spine surgery.

SUMMARY OF BACKGROUND DATA

Venous thromboembolism (VTE) is a serious complication after major spinal reconstructive surgery in adults. Specifically, pulmonary embolism (PE) can result in significant morbidity and mortality, and it has been reported in up to 13% of patients. Prophylactic IVC filter placement was initiated for all "high-risk" spinal surgery patients after a pilot study demonstrated decreased VTE-related morbidity and mortality.

METHODS

After institutional review board approval, the medical records of all patients receiving an IVC filter at a single institution from 2000 to 2007 were reviewed. Age, sex, surgical approach, postoperative deep vein thrombosis (DVT), postoperative superficial thrombus, presence of pulmonary or paradoxical embolus, mortality, and IVC filter complications were all evaluated. Indications for IVC filter placement included history of DVT or PE, malignancy, hypercoagulability, prolonged immobilization, staged procedures of longer than 5 segment levels, combined anterior-posterior approaches, iliocaval manipulation during exposure, and anesthetic time of more than 8 hours. Descriptive statistics were used for the analysis of patient characteristics. Nonparametric frequency statistics (odds ratios [OR], χ) were used for analysis of main outcomes.

RESULTS

A total of 219 patients (150 women, 69 men) with a mean age of 58.8 (range, 17-86) years, were analyzed. There were 2 complications from IVC filter placement (66 Greenfield filters; 157 retrievable filters). The incidence of lower extremity DVT was 18.7% (41/219) in 36 patients. PE incidence was 3.7% (8/219 patients), and the paradoxical embolus rate was 0.5% (1 patient). Prophylactic IVC filter use reduced the odds of developing a pulmonary embolus (OR = 3.7, P < 0.05) compared with population controls. Patients receiving Greenfield filters had significantly higher VTE incidence than those receiving retrievable filters (OR = 2.8, P = 0.008). Anesthesia duration of more than 8 hours significantly increases VTE incidence (P = 0.029). No statistical significance (P < 0.05) was noted with combined anterior-posterior approach (118 patients) versus posterior-only approach (101 patients) and the incidence of DVT (24/118, 20.3% for former; 17/101, 16.8% for latter). There were a total of 14 deaths; none related to PE or paradoxical embolism during an 8-year period. Mean and median follow-up was 2.8 and 2.4 years, respectively, with 126 achieving 2 or more years of follow-up.

CONCLUSION

VTE-related morbidity and mortality have heightened the awareness within the spine community to the perioperative management of patients undergoing major spinal reconstruction. Prophylactic IVC filter placement significantly lowers VTE-related events, including PE development, than population controls.

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.

Filtro de veia cava: uma década de experiência em um centro de trauma nível I

OBJETIVO: Avaliar os dados relativos à utilização de filtro de veia cava na Divisão de Trauma do Centro Médico da UCSD San Diego, CA/EUA. MÉTODOS: Estudo descritivo realizado na Divisão de Trauma visando avaliar a experiência acumulada e a conduta terapêutica nos doentes atendidos pela equipe da Divisão de Trauma e submetidos à colocação de filtro de veia cava como método de prevenção ou tratamento do TEP no período de janeiro de 1999 a dezembro de 2008. RESULTADOS: O estudo compreendeu 512 doentes, destacando-se o sexo masculino (73%). Quanto à causa do traumatismo predominou o acidente automobilístico, seguido por lesões provocadas por quedas. A relação homem/mulher foi 3:1. A faixa etária mais atingida foi 21 a 40 anos, representando 36% dos doentes. O percentual de filtros de cava profiláticos foi de 82% contra 18% de filtros terapêuticos. O traumatismo craniano foi a principal causa para indicação de filtros profiláticos seguido dos traumas raquimedulares. O índice de TVP pós-filtro foi 11%. CONCLUSÃO: Na presença de contraindicação ao uso de anticoagulantes em doentes vítimas de trauma grave, os filtros de veia cava inferior demonstraram ser uma opção efetiva e segura. Entretanto, deve-se aplicar rigor ao julgamento clínico para todas as indicações, mesmo após o advento de filtros "recuperáveis".

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.

Randomized controlled trials affecting polytrauma care

Trauma remains the leading cause of death in the world in patients under 45 years of age. The evaluation, resuscitation, and appropriate management of polytraumatized patients are paramount to successful outcomes. The advance of evidence-based medicine has had a powerful and positive impact on trauma care, even though the nature of many traumatic injuries lends itself poorly to study in a randomized fashion. During the initial management of bleeding patients, hypotensive resuscitation prior to surgical control has found strong support in the literature, and its use has been adopted by many surgeons. Head injury is the most common cause of traumatic death, and while high-level evidence is limited, adherence to management guidelines is associated with improved outcomes. For abdominal trauma, the concept of damage control surgery, while popular, has never been put to the test in a randomized controlled trial. Numerous randomized trials in the field of critical care have affected the management of severely injured patients, including intensive insulin therapy and low tidal volume ventilation in patients with compromised respiratory function. Finally, a multidisciplinary approach to trauma care in designated trauma centers allows for improved outcomes in polytraumatized patients.

Optional inferior vena cava filters in the trauma patient

Trauma patients are at exceedingly high risk of development of venous thromboembolism (VTE) including deep venous thrombosis and pulmonary embolism (PE). The epidemiology of VTE in trauma patients is reviewed. PE is thought to be the third major cause of death after trauma in those patients who survive longer than 24 hours after onset of injury. In fact, patients recovering from trauma have the highest rate of VTE among all subgroups of hospitalized patients. Various prophylactic and surveillance methods have been evaluated and found helpful in certain situations, but VTE complications can occur despite such measures. Therapeutic and prophylactic uses of inferior vena cava (IVC) filters in trauma patients are reviewed. Prophylactic IVC filter use is revealed to be a controversial subject with valid arguments on both sides of the issue. With the lack of prospective randomized trials of IVC filter use in trauma, it is impossible to make evidence-based recommendations. Unfortunately, two sets of guidelines are available for insertion of filters in trauma patients, with conflicting recommendations. The introduction of retrievable IVC filters seems to offer a unique solution for VTE protection in the trauma patient population, which often consists of younger members of our population. Lastly, current generations of FDA-approved retrieval filters are discussed.

Deep vein thrombosis prophylaxis in trauma patients

Deep vein thrombosis (DVT) and pulmonary embolism (PE) are known collectively as venous thromboembolism (VTE). Venous thromboembolic events are common and potentially life-threatening complications following trauma with an incidence of 5 to 63%. DVT prophylaxis is essential in the management of trauma patients. Currently, the optimal VTE prophylaxis strategy for trauma patients is unknown. Traditionally, pelvic and lower extremity fractures, head injury, and prolonged immobilization have been considered risk factors for VTE; however it is unclear which combination of risk factors defines a high-risk group. Modalities available for trauma patient thromboprophylaxis are classified into pharmacologic anticoagulation, mechanical prophylaxis, and inferior vena cava (IVC) filters. The available pharmacologic agents include low-dose heparin (LDH), low molecular weight heparin (LMWH), and factor Xa inhibitors. Mechanical prophylaxis methods include graduated compression stockings (GCSs), pneumatic compression devices (PCDs), and A-V foot pumps. IVCs are traditionally used in high risk patients in whom pharmacological prophylaxis is contraindicated. Both EAST and ACCP guidelines recommend primary use of LMWHs in trauma patients; however there are still controversies regarding the definitive VTE prophylaxis in trauma patients. Large randomized prospective clinical studies would be required to provide level I evidence to define the optimal VTE prophylaxis in trauma patients.

Death and venous thromboembolism after lower extremity amputation

BACKGROUND

Lower extremity amputation is often performed in patients with end-stage vascular disease and is considered a high-risk procedure. Uncertainty exists about the rate of venous thromboembolism (VTE) in these patients.

OBJECTIVES

To establish the incidence of death and venous thromboembolism after lower extremity amputation.

METHODS

A prospective cohort study was performed to establish the incidences of death and VTE after lower extremity amputation, as detected by bilateral complete compression ultrasonography and ventilation-perfusion scintigraphy performed preoperatively and around day 14 postoperatively. Standard low-molecular-weight heparin thromboprophylaxis was given during the study period. A secondary outcome was the incidences of mortality and symptomatic venous thromboembolic complications during 8 weeks of postoperative follow-up.

RESULTS

Forty-nine patients (53 amputations) were ultimately included in the intention-to-treat analysis. Five patients died within the 2-week period and an additional seven patients died during the 8 weeks clinical follow-up period. The total mortality rate therefore was 12 of 53 amputations [22.6%; 95% confidence interval (CI), 12.3-36.2%]. Six patients developed pulmonary embolisms (of which two were fatal) and one patient developed an asymptomatic contralateral distal deep venous thrombosis, resulting in a total VTE rate of 7 out of 53 amputations (13.2%; 95% CI, 5.47-25.3%).

CONCLUSION

Lower extremity amputation is accompanied by a high mortality rate from sepsis, and respiratory and vascular causes. This study shows that VTE substantially contributes to the morbidity and mortality after lower extremity amputation despite adequate pharmacological thromboprophylaxis in this vulnerable population of patients.

Complications related to deep venous thrombosis prophylaxis in trauma: a systematic review of the literature

Deep venous thrombosis prophylaxis is essential to the appropriate management of multisystem trauma patients. Without thromboprophylaxis, the rate of venous thrombosis and subsequent pulmonary embolism is substantial. Three prophylactic modalities are common: pharmacologic anticoagulation, mechanical compression devices, and inferior vena cava filtration. A systematic review was completed using PRISMA guidelines to evaluate the potential complications of DVT prophylactic options. Level one evidence currently supports the use of low molecular weight heparins for thromboprophylaxis in the trauma patient. Unfortunately, multiple techniques are not infrequently required for complex multisystem trauma patients. Each modality has potential complications. The risks of heparin include bleeding and heparin induced thrombocytopenia. Mechanical compression devices can result in local soft tissue injury, bleeding and patient non-compliance. Inferior vena cava filters migrate, cause inferior vena cava occlusion, and penetrate the vessel wall. While the use of these techniques can be life saving, they must be appropriately utilized.

Thromboprophylaxis for trauma patients

This is the protocol for a review and there is no abstract. The objectives are as follows: To assess the effects of thromboprophylaxis in trauma patients on mortality and incidence of DVT and PE. To compare the effects of different thromboprophylaxis interventions and their relative effects according to the type of trauma.