Prevention of Venous Thromboembolism in High-Risk Patients

Implementation of a Standardized Renal Trauma Protocol at a Level 1 Trauma Center: 7-Year Protocol and 10-Year Institutional Review

Objective

Current urologic renal trauma guidelines favor conservative management. In 2012, we implemented an institution-wide renal trauma protocol to standardize management. This protocol details initiation of DVT (deep vein thrombosis) prophylaxis, cessation of bed rest, and frequency of laboratory studies. We hypothesized that low-grade injuries (grade I–III) could be managed without urologic consultation and that our chemical DVT prophylaxis regimen would not pose an increased risk of hemorrhage requiring transfusion.

Methods

We performed a cross-sectional analysis of a prospectively maintained database containing all renal trauma at our institution from 2009 to 2019. We segregated injuries based on grade, presence of multi-organ trauma, and evaluated the presence and types of intervention, initiation of chemical DVT prophylaxis, and post-DVT prophylaxis hemorrhage requiring transfusion.

Results

We identified 295 cases of renal trauma, of which 62 were isolated injuries. Forty-three of the isolated renal injuries were transferred from outside facilities, 70% of which were classified as low-grade injuries. There were 220 low-grade lacerations and 75 high-grade lacerations. No grade I or II lacerations required any interventions. Two (2.5%) grade III lacerations required IR embolization. Twenty-five (41%) grade IV lacerations required intervention, of which five were nephrectomy. Seven (54%) grade V lacerations required intervention, of which 5 were nephrectomies. Upon review of our protocol with early ambulation and DVT prophylaxis, there were no cases of isolated renal injury where initiation of either treatment resulted in delayed hemorrhage requiring transfusion or surgical intervention.

Conclusion

Only 2/220 low-grade renal lacerations required intervention. Our data suggest that grade I and II renal lacerations can be managed safely without urologic consultation. Consultation is warranted for grade III injuries given the possibility of initial understaging. Furthermore, we believe our renal laceration protocol in our admittedly small, isolated sample has shown our DVT prophylaxis initiation to not pose increased risk.

The Impact of D-Dimer on Postoperative Deep Vein Thrombosis in Patients with Thoracolumbar Fracture Caused by High-Energy Injuries

Objective

To investigate the dynamic variation of D-dimer and to evaluate the efficacy and accuracy of D-dimer level in patients with thoracolumbar fractures caused by high-energy injuries.

Methods

A total of 121 patients with thoracolumbar fractures caused by high-energy injuries were retrospectively identified and included in this study. There were 83 males and 38 females, with an average age of 48.6 ± 11.2 years. All patients were treated with either screw fixation surgery or decompression fixation surgery. The D-dimer levels were measured 1 day before surgery and on the first, third, and fifth days after surgery. The dynamic variation of D-dimer and the effects of risk factors on D-dimer levels were analysed. A receiver operating characteristic (ROC) curve analysis was performed and the appropriate D-dimer cut-off level was determined for deep vein thrombosis (DVT) screening.

Results

Due to a trough on the third day, D-dimer levels grew in an unsustainable manner following surgery (P < 0.001). Patients with the operation time >120 min (P = 0.009) and those with an American Spinal Injury Association (ASIA) score A-C (P < 0.001) had higher D-dimer levels. The area under the curve of D-dimer was the greatest on the third day. Applying stratified cut-off values did not change the sensitivity, specificity and negative predictive value in the group with an operation time >120 min, and ASIA score A-C group.

Conclusions

D-dimer levels elevated with fluctuation in patients with thoracolumbar fractures caused by high-energy injuries after surgery. Both operation time and ASIA score had an impact on D-dimer levels. Regarding DVT diagnoses, the diagnostic value of D-dimer was highest on the third day postoperatively, and stratified cut-off values by these two factors did not show better diagnostic efficacy compared with a collective one.

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.

American Society of Hematology 2021 guidelines on the use of anticoagulation for thromboprophylaxis in patients with COVID-19

BACKGROUND

Coronavirus disease 2019 (COVID-19)-related critical illness and acute illness are associated with a risk of venous thromboembolism (VTE).

OBJECTIVE

These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in decisions about the use of anticoagulation for thromboprophylaxis for patients with COVID-19-related critical illness and acute illness who do not have confirmed or suspected VTE.

METHODS

ASH formed a multidisciplinary guideline panel and applied strict management strategies to minimize potential bias from conflicts of interest. The panel included 3 patient representatives. The McMaster University GRADE Centre supported the guideline-development process, including performing systematic evidence reviews (up to 19 August 2020). The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, including GRADE Evidence-to-Decision frameworks, to assess evidence and make recommendations, which were subject to public comment.

RESULTS

The panel agreed on 2 recommendations. The panel issued conditional recommendations in favor of prophylactic-intensity anticoagulation over intermediate-intensity or therapeutic-intensity anticoagulation for patients with COVID-19-related critical illness or acute illness who do not have confirmed or suspected VTE.

CONCLUSIONS

These recommendations were based on very low certainty in the evidence, underscoring the need for high-quality, randomized controlled trials comparing different intensities of anticoagulation. They will be updated using a living recommendation approach as new evidence becomes available.

Venous Thromboembolism Prediction in Postoperative Urogynecology Patients: The Utility of Risk Assessment Tools

OBJECTIVES

The aim of the study was to evaluate the utility of risk assessment tools (Rogers and Caprini Score models) in predicting venous thromboembolism (VTE) in a urogynecology patient population.

METHODS

All surgical patients underwent a procedure in the operating room with 1 of 7 female pelvic medicine and reconstructive surgery.Attendings from January 1 to December 31, 2015, were investigated. Rogers and Caprini Scores were calculated for each patient as well as the occurrence of any VTE in the 30 days after surgery. Patients were then grouped into risk categories based on the American College of Chest Physicians guidelines.

RESULTS

A total of 783 patients were identified and included in this study. The average patient age was 58 years (range = 18-89 years). The average operative time was 109 minutes (range = 4-491 minutes). Most patients obtained a Rogers Score of 5 (32%) and a Caprini Score of 4 (34%). Based on Caprini scoring, the American College of Chest Physicians category distribution was as follows: 10% low risk, 61% moderate risk, and 29% high risk. Based on Rogers scoring, this distribution was as follows: 96.8% very low risk, 3.1% low risk, and 0.1% moderate risk. Two VTE events were identified in the cohort. Overall, the incidence of VTE was 0.26%.

CONCLUSIONS

The standard VTE risk assessment tools grade urogynecology patients very differently. Although the Caprini Scale seems to appropriately differentiate individual patient VTE risk, the Rogers Scale does not adequately stratify this risk, thus potentially limiting its use within this population.

Comparison of two pharmacological prophylaxis strategies for venous thromboembolism in spinal cord injury patients: a retrospective study

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To compare the cost and incidence of venous thromboembolism (VTE) and bleeding between two different VTE pharmacological prophylaxis strategies in individuals with spinal cord injury: one based on motor impairment (Protocol 1) and the other based on time from the lesion and presence of associated risk factors for VTE (Protocol 2).

SETTING

A tertiary rehabilitation hospital in Brazil.

METHODS

We retrospectively reviewed a total of 1475 charts of individual admissions: 814 individuals received pharmacological prophylaxis according to Protocol 1 and 661 according to protocol 2. These cohorts were compared with respect to age, time and level of injury, length of stay, AIS classification, type of injury, and occurrence of VTE and major bleeding. The number of prescribed doses of enoxaparin and expenditures associated with enoxaparin during each period were evaluated.

RESULTS

The median lesion time was 3 years. The risk-based strategy drastically reduced the average monthly use of enoxaparin by 75% and the 12-month enoxaparin expenditure by $119,930.33, without increasing the risk of VTE. The incidence density of thromboembolic events was 0.55/10,000 patient-days, and all events occurred in individuals receiving prophylaxis according to Protocol 1.

CONCLUSIONS

Time from injury and risk of VTE-based protocol for indication of pharmacological prophylaxis drastically reduced costs. No difference in occurrence of VTE was observed.

Thromboembolism in the Sub-Acute Phase of Spinal Cord Injury: A Systematic Review of the Literature

To review the evidence of thromboembolism incidence and prophylaxis in the sub-acute phase of spinal cord injury (SCI) 3-6 months post injury. All observational and experimental studies with any length of follow-up and no limitations on language or publication status published up to March 2015 were included. Two review authors independently selected trials for inclusion and extracted data. Outcomes studied were incidence of pulmonary embolism (PE) and deep vein thrombosis (DVT) in the sub-acute phase of SCI. The secondary outcome was type of thromboprophylaxis. Our search identified 4305 references and seven articles that met the inclusion criteria. Five papers reported PE events and three papers reported DVT events in the sub-acute phase of SCI. Studies were heterogeneous in populations, design and outcome reporting, therefore a meta-analysis was not performed. The included studies report a PE incidence of 0.5%-6.0% and DVT incidence of 2.0%-8.0% in the sub-acute phase of SCI. Thromboprophylaxis was poorly reported. Spinal patients continue to have a significant risk of PE and DVT after the acute period of their injury. Clinicians are advised to have a low threshold for suspecting venous thromboembolism in the sub-acute phase of SCI and to continue prophylactic anticoagulation therapy for a longer period of time.

Low-molecular-weight heparin and intermittent pneumatic compression for thromboprophylaxis in critical patients

The efficacy and safety of physiotherapeutic prophylaxis for venous thromboembolism in critically ill patients with heparin contraindication remains unclear. In the present study it was hypothesized that physiotherapy prophylaxis with intermittent pneumatic compression (IPC) would be safe and effective for patients unable to receive low-molecular-weight heparin (LMWH). In addition, this study investigated whether a combined therapy of IPC with LMWH would be more effective for the prophylaxis of deep vein thrombosis (DVT) in critical patients. A total of 500 patients were divided into four groups according to the prophylaxis of DVT. The IPC group consisted of 95 patients with heparin contraindication that received IPC treatment; the LMWH group consisted of 185 patients that received an LMWH injection; the LMWH + IPC group consisted of 75 patients that received IPC treatment and LMWH injection; and the control group consisted of 145 patients that received no IPC treatment or injection of LMWH. Each patient was evaluated clinically for development of DVT and the diagnosis was confirmed by Doppler study. Venous thromboembolism was a common complication among the trauma patients with severe injuries. Patients responded positively to the treatment used in the intervention groups. Patients exhibited an improved response to LMWH + ICP compared with IPC or LMWH alone, while no significant difference was detected between the IPC and LMWH groups. These results were applicable to patients that had a Wells score of ≥3; however, no significant differences in DVT incidence were observed among the patients who had a Wells score of <3. In this observational study, LMWH + ICP appeared to be more effective than either treatment alone in treating critically ill trauma patients with severe injuries that are at high risk for VTE and bleeding simultaneously.

d-Dimer as a Screening Marker for Venous Thromboembolism After Surgery Among Patients Younger Than 50 With Lower Limb Fractures

OBJECTIVE

For the present study, the authors hypothesized that the d-dimer levels would be systematically raised in a postoperative population of patients younger than 50 with lower limb fractures and to define a feasible cutoff value for identification of venous thromboembolism (VTE).

METHODS

Doppler ultrasonography of lower limbs was performed pre- and postoperatively to evaluate for deep vein thrombosis in 150 patients who underwent open reduction and internal fixation (ORIF). Plasma d-dimer levels were assessed 2 days before surgery and on the 3rd, 7th, and 10th days after surgery. Statistical analysis was carried out to define a feasible threshold for the d-dimer levels.

RESULTS

Plasma d-dimer levels were found to be systematically raised postoperatively, and they differed between patients with and without VTE significantly. On the third day after surgery, d-dimer levels of more than 3 mg/L indicated VTE with a sensitivity of 88.37% and a specificity of 96.96%, allowing for the definition of a feasible cutoff value. Duration of surgery, duration of tourniquet, ventilation time, and time of postoperative immobility of lower limbs were identified as highly significant risk factors for the development of VTE.

CONCLUSION

Using a threshold of 3 mg/L, the d-dimer levels will screen out VTE with a high degree of sensitivity and specificity in younger patients who have undergone ORIF for lower limb fractures.

Late Venous Thromboembolism Prophylaxis after Craniotomy in Acute Traumatic Brain Injury

The objective of this study is to compare rates of venous thromboembolism (VTE) in patients who receive enoxaparin prophylaxis compared with no enoxaparin prophylaxis after craniotomy for traumatic brain injury (TBI). This retrospective cohort evaluated all trauma patients admitted to a Level I trauma center from January 2006 to December 2011 who received craniotomy after acute TBI. Patients were excluded if developed VTE before administration of enoxaparin or they died within the first 72 hours of hospital admission. A total of 271 patients were included (enoxaparin prophylaxis, n = 45; no enoxaparin prophylaxis, n = 225). The median time until enoxaparin initiation was 11 ± 1 days. There was no significant difference in the proportion of patients who developed a VTE when using enoxaparin prophylaxis compared with no enoxaparin prophylaxis (2 vs 4%; P = 0.65). Rates of deep vein thrombosis (2 vs 3%; P = 0.87) and pulmonary embolism (0 vs 1%; P = 0.99) were similar between treatment groups, respectively. Late enoxaparin prophylaxis did not demonstrate a protective effect for VTE. Given the overall low event rate, the administration of pharmacologic prophylaxis against VTE late in the treatment course may not be routinely warranted after craniotomy for acute TBI. Further investigation with early administration of enoxaparin is needed.

Evaluation of thromboprophylaxis in medium-sized general hospital

CONTEXT: Deep vein thrombosis (DVT) is a serious, common disease whose complications include pulmonary thromboembolism (PTE) and postthrombotic syndrome. The importance and benefits of correct and effective pharmacological prophylaxis for DVT are well documented. OBJECTIVES: The aims of this study were to evaluate adequacy of prophylaxis for DVT and PTE at the Santa Casa de Misericórdia de Ponta Grossa (SCMPG), Paraná, Brazil, and determine risk stratification for patients hospitalized in this institution. METHODS: A cohort study was conducted to assess DVT prophylaxis of patients hospitalized on May 15th, 2009. The study population consisted of a sample of 104 patients, subdivided into clinical and surgical groups and stratified into different specialties. Correct use of DVT prophylaxis was evaluated according to recommendations published by The Brazilian Society for Angiology and Vascular Surgery and took into account prophylactic methods specified explicitly in information found in each patient's medical chart. RESULTS: Of the 104 patients interviewed, 51 (49.04%) were clinical patients and 53 (50.96%) surgical. Based on risk stratification, 17 (16.35%) were classified as low risk, 37 (35.58%) as moderate risk, 46 (44.23%) as high risk and 4 (3.85%) as extremely high risk for DVT/PTE. A total of 68 patients (65.38%) received prophylaxis, but of these only 56 (53.85%) received the correct prophylaxis, and 36 (34.62%) did not receive any prophylaxis. CONCLUSION: The rates of prophylaxis use for DVT and PTE in this service are higher than rates published in the literature.

A retrospective analysis of the effectiveness of low molecular weight heparin for venous thromboembolism prophylaxis in trauma patients

BACKGROUND

In trauma patients, Enoxaparin (a low molecular weight heparin, LMWH) prophylaxis for venous thromboembolism (VTE) risk reduction is unproven.

METHODS

Cohort analysis conducted consisting of all trauma patients age >13 admitted to Level-I trauma center and hospitalized >48 hours. VTE risk determined by the Risk Assessment Profile. High risk patients received LMWH unless contraindicated, while low and moderate risk patients received LMWH at attending surgeon's discretion. Odds ratio for VTE by logistic regression. VTE incidence, relative risk (RR), and number needed to treat (NNT) to prevent deep vein thrombosis (DVT) or pulmonary embolism determined by risk category.

RESULTS

Cohort consisted of 2,281 patients (1,211 low, 979 moderate, 91 high risks). VTE occured in 254 patients (11.1%). High-risk patients had significantly higher VTE incidence, odds ratio = 31.8 (P < .001). VTE was significantly reduced in high-risk patients receiving LMWH versus those who did not (.26 vs .53, P = .02). Among moderate and high risk, prophylactic LMWH reduced the incidence of pulmonary embolism (RR = .19, NNT = 40.4, P = .01), and trended toward reduced DVT incidence (RR = .81, NNT = 27.3, P = .15). LMWH lowered DVT incidence (RR = .52, NNT = 4.1, P = .03) in high risk patients.

CONCLUSION

Prophylactic LMWH is associated with reduction of VTE in trauma 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".

Early lower extremity fracture fixation and the risk of early pulmonary embolus: filter before fixation?

BACKGROUND

Venous thromboembolism is a major cause of morbidity and mortality after injury. Prophylactic anticoagulation is often delayed as a result of injuries or required procedures. Those patients at highest risk in this early vulnerable window postinjury are not well characterized. We sought to determine those patients at highest risk for an early pulmonary embolism (PE) after injury.

METHODS

A retrospective analysis using data derived from a large state wide trauma registry (1997-2007) was performed. Patients with a documented PE and time of occurrence were selected (n = 712). Patients with fat emboli and lower extremity vascular injuries were excluded. Patients with a PE within the first 72 hours of admission (EARLY, n = 122) were compared with those with DELAYED presentation. Kaplan-Meier survival analysis was used to characterize the timing of death between the two groups. Backward stepwise logistic regression was used to determine independent risk factors for EARLY PE relative to those with DELAYED PE.

RESULTS

EARLY and DELAYED groups were similar in age, gender, Glasgow Coma Scale, emergency department systolic blood pressure, and injury mechanism. The EARLY PE group had a lower Injury Severity Score but injuries more commonly included femur fracture. Kaplan-Meier analysis revealed that EARLY PE patients have a significantly higher risk of early mortality relative to DELAYED PE patients (p = 0.012). Regression analysis revealed that the only independent risk factor for EARLY PE was lower extremity/pelvic orthopedic fixation (<48 hours from injury). The risk of EARLY PE was more than threefold higher (odds ratios, 3.85; 95% CI, 1.9-7.6; p < 0.001) for those who underwent early lower extremity orthopedic fixation versus those who did not.

CONCLUSION

Early lower extremity/pelvis orthopedic fixation is the single independent predictor of EARLY PE in this patient cohort. Venous thromboembolism/PE prevention strategies should be made a priority in this group of patients, including early preoperative institution of anticoagulation prophylaxis. These results suggest that those with contraindications to early anticoagulation may benefit from insertion of retrievable inferior vena cava filters preoperatively.

Pulmonary embolism prophylaxis with inferior vena cava filters in trauma patients: a systematic review using the meta-analysis of observational studies in epidemiology (MOOSE) guidelines

Prophylactic inferior vena cava filters (pIVCFs) for the prevention of pulmonary embolism (PE) are controversial. Current practice guidelines (EAST and ACCP) are based on the critical appraisal of observational studies. As a result, their recommendations are conflicting and may account for practice pattern variation. The purpose of this study is to critically review the available literature and ascertain the level of evidence both for and against the use of pIVCFs for PE prophylaxis in trauma patients. We searched PubMed and Web of Science for publications from 1950 until July 2010 that assessed the efficacy of PE prevention with pIVCFs in the trauma population. We followed the MOOSE (Meta-analysis of Observational Studies in Epidemiology) guidelines for design, implementation, and reporting. The Newcastle-Ottawa Score was used for quality and comparability assessment. Seven observational studies met inclusion criteria for this meta-analysis, representing 1,900 patients. Only one study was published in this decade. The rate of PE was statistically lower in the IVCF group compared to a matched control group without IVCFs (OR 0.21, 95% CI 0.09-0.49). There was no significant difference in DVT. Using the MOOSE criteria these results show a decreased likelihood of PE among trauma patients who receive pIVCFs. Although these results could favor the placement of pIVCFs, the lack of contemporary use of pharmacologic prophylaxis across studies does not allow us to make firm conclusions either for or against the routine use of pIVCFs. Prospective randomized trials are needed to determine the role of pIVCFs in high-risk trauma patients.

Inferior vena caval filter insertion prior to bariatric surgery: a systematic review of the literature

Placement of inferior vena cava filters (IVCFs) is considered in many patients undergoing bariatric surgery. Their placement is driven by a high rate of pulmonary embolism (PE), uncertainty as to the effectiveness of pharmacologic prophylaxis, and a lack of alternate methods to prevent pulmonary embolism. We performed a systematic review of the literature to evaluate the evidence supporting placement of IVCFs in patients undergoing bariatric surgery. Eleven studies were identified; none were randomized trials. Descriptive analysis suggests that IVCFs reduced PE; however, the strength of this observation is tempered by the lack of use of effective forms of prophylaxis and the failure to account for complications of IVCF placement. We conclude, pending the results of controlled studies, that the use of IVCFs cannot be recommended for routine patients undergoing bariatric surgery.

Incidence and risk factors for deep venous thrombosis after moderate and severe brain injury

BACKGROUND

Patients with traumatic injuries possess a high risk of developing deep venous thrombosis (DVT), thus the need for appropriate prophylaxis. Patients with head injuries pose a unique challenge due to contraindication to the use of anticoagulation. We sought to determine the incidence of DVT and identify specific risk factors for its development in patients with head injuries.

METHODS

All head injury admissions between January 1, 2000, and July 31, 2006, with a length of stay >or=7 days were identified. Patient data including age, sex, injuries, Glasgow Coma Scale, Injury Severity Score (ISS), and venous duplex scan results were collected. Mechanical methods were routinely used for prophylaxis; heparin was not used in this population. Weekly duplex screening was commenced at 7 days to 10 days after admission.

RESULTS

There were 939 patients who met criteria for review, however, duplex scans were performed in only 677, which was the population studied. Overall, DVT was present in 31.6%. There were fewer DVTs in patients with isolated head injuries (25.8%) compared with patients with those with head and extracranial injuries (34.3%)--p = 0.026. Independent predictors for DVT identified included male gender (p = 0.04), age >or=55 (p < 0.001), ISS >or=15 (p = 0.014), subarachnoid hemorrhage (p = 0.006), and lower extremity injury (p = 0.001).

CONCLUSIONS

DVT occurs in one third of moderately to severely brain injured patients. Isolated head injuries have a lower incidence. Older age, male gender, higher ISS, and the presence of a lower extremity injury are strong predictors for developing DVT. Regular screening and the use of prophylactic inferior vena cava filters in patients with risk factors should be strongly considered.

An economic evaluation of venous thromboembolism prophylaxis strategies in critically ill trauma patients at risk of bleeding

BACKGROUND

Critically ill trauma patients with severe injuries are at high risk for venous thromboembolism (VTE) and bleeding simultaneously. Currently, the optimal VTE prophylaxis strategy is unknown for trauma patients with a contraindication to pharmacological prophylaxis because of a risk of bleeding.

METHODS AND FINDINGS

Using decision analysis, we estimated the cost effectiveness of three VTE prophylaxis strategies-pneumatic compression devices (PCDs) and expectant management alone, serial Doppler ultrasound (SDU) screening, and prophylactic insertion of a vena cava filter (VCF) -- in trauma patients admitted to an intensive care unit (ICU) with severe injuries who were believed to have a contraindication to pharmacological prophylaxis for up to two weeks because of a risk of major bleeding. Data on the probability of deep vein thrombosis (DVT) and pulmonary embolism (PE), and on the effectiveness of the prophylactic strategies, were taken from observational and randomized controlled studies. The probabilities of in-hospital death, ICU and hospital discharge rates, and resource use were taken from a population-based cohort of trauma patients with severe injuries (injury severity scores >12) admitted to the ICU of a regional trauma centre. The incidence of DVT at 12 weeks was similar for the PCD (14.9%) and SDU (15.0%) strategies, but higher for the VCF (25.7%) strategy. Conversely, the incidence of PE at 12 weeks was highest in the PCD strategy (2.9%), followed by the SDU (1.5%) and VCF (0.3%) strategies. Expected mortality and quality-adjusted life years were nearly identical for all three management strategies. Expected health care costs at 12 weeks were Can$55,831 for the PCD strategy, Can$55,334 for the SDU screening strategy, and Can$57,377 for the VCF strategy, with similar trends noted over a lifetime analysis.

CONCLUSIONS

The attributable mortality due to PE in trauma patients with severe injuries is low relative to other causes of mortality. Prophylactic placement of VCF in patients at high risk of VTE who cannot receive pharmacological prophylaxis is expensive and associated with an increased risk of DVT. Compared to the other strategies, SDU screening was associated with better clinical outcomes and lower costs.

Traumatic brain injury is associated with the development of deep vein thrombosis independent of pharmacological prophylaxis

INTRODUCTION

Deep venous thrombosis (DVT) is common among trauma patients. If left untreated it may result in lethal pulmonary thromboembolism. Previous studies have suggested that intracranial hemorrhage serves as an independent risk factor for the development of DVT. These studies were not able to exclude anticoagulation therapy as a confounding variable in their analysis. Our objective was to determine the association of traumatic brain injury (TBI) to the formation of DVT irrespective of the use of anticoagulation therapy.

METHODS

All patients admitted to an academic level I Trauma Center between 2000 and 2007 with blunt or penetrating injuries were selected for inclusion in this study. Patients who died or who were discharged within 24 hours of admission were excluded in the analysis. TBI was defined as any intraparenchymal hemorrhage or extra-axial intracranial bleeding identified on radiographic imaging or both. Anticoagulation therapy was defined as the uninterrupted use of either subcutaneous lovenox or heparin. Risk ratios and 95% confidence intervals compared the risk of DVT among patients with and without TBI according to the initiation of anticoagulation therapy (no therapy, <24 hours, 24-48 hours, and >48 hours) adjusted for age, gender, race, injury severity, mechanism of injury, spinal injury, and lower extremity fracture.

RESULTS

Irrespective of the time of initiation of pharmacologic prophylaxis, TBI is independently associated with the formation of DVT. A threefold to fourfold increased risk of DVT formation is consistent across all prophylaxis groups among patients with TBI.

CONCLUSION

The incidence of DVT among injured patients with TBI is significantly higher than those patients without head injury independent of anticoagulation therapy. Rigorous surveillance to detect DVT among trauma patients with TBI should be undertaken and where appropriate alternate means for pulmonary thromboembolism prevention used.

The impact of preinjury antiplatelet and anticoagulant pharmacotherapy on outcomes in elderly patients with hemorrhagic brain injury

BACKGROUND

More elderly trauma patients are identified with preinjury use of clopidogrel, aspirin, or warfarin (CAW). The purpose of this study was to determine whether preinjury CAW use was an important predictor of mortality in patients aged >or=50 years with blunt, hemorrhagic brain injury (HBI).

METHODS

A retrospective review of patients with blunt, HBI aged >or=50 years with subgroup analysis for older (>70 years) and younger (50-70 years) patients was performed. CAW use was analyzed for differences in age, gender, hospital length of stay (LOS), Injury Severity Score (ISS), Glasgow Coma Score (GCS), mechanism of injury (MOI), platelet transfusion therapy (PLT), disposition at discharge, and in-hospital mortality.

RESULTS

From January 2003 to October 2005, 416 patients were identified. The mean age was 69+/-1 years. No differences were found for ISS (24 +/- 0.5), GCS (12 +/- 0.2), or LOS (8 +/- 0.4 days). CAW use was present in 40% of patients and significantly higher in older patients. Mortality was not different between older and younger CAW(+) patients, but it significantly increased for older CAW(-) patients. Significant predictors of death included age, ISS, and GCS (P<.02).

CONCLUSIONS

Preinjury CAW use in older blunt, HBI patients is not associated with increased mortality. Age was a significant predictor of mortality independent of CAW use.

Primary prophylaxis of venous thromboembolism in surgical patients

Venous thromboembolism is a major risk for surgical patients during the perioperative period. Prevention of perioperative venous thromboembolism remains a critical component of surgical patient care. The risk for venous thromboembolism in surgical patients can be stratified by their risk factors and by the type of operation. Pharmacological prophylaxis for venous thromboembolism includes unfractionated heparin, low-molecular weight heparin, fondaparinux, warfarin, antiplatelet therapy, and direct thrombin inhibitors. Mechanical devices such as graduated compression stockings, intermittent pneumatic compressions, and venous foot pumps are also effective modalities for venous thromboembolism prophylaxis. The optimal preventive measure of venous thromboembolism should be based on the degree of risk for venous thromboembolism with the intensity of prophylaxis while balancing potential treatment benefits and risks in each individual patient. The epidemiology of venous thromboembolism, the methods for achieving venous thromboembolism prophylaxis, and the approach to institute venous thromboembolism prophylaxis in surgical patients undergoing various operative interventions are reviewed in this article.

Supportive management of patients with brain tumors

Management issues for patients with brain tumors include peritumoral edema, symptomatic seizures, venous thromboembolism, headache, pain, fatigue and neuropsychological complaints. Vasogenic edema is typically ameliorated with the lowest dose possible of corticosteroid. Seizures are managed with attention to additional or complicated side effects of antiepileptic drugs and their interactions with chemotherapy, and primary prevention with antiepileptic medications is not recommended. Appropriate treatments for headache, pain, fatigue and neuropsychological complaints are important, but are not yet well standardized. Above all, patients' personal goals regarding their priorities at the end of life have the most importance.

Inferior vena cava filters in the management of venous thromboembolism

Inferior vena cava (IVC) filters, both retrievable and permanent, are indicated for the prevention of pulmonary embolism (PE) in patients contraindicated for anticoagulant therapy, in those with anticoagulant therapy complications, and perhaps for those with recurrent PE despite therapeutic anticoagulation. Because of the lack of randomized controlled trials (only 1 has been published), clinicians have little evidence-based information to assist them in determining proper use of IVC filters. The introduction of retrievable filters and the ease of insertion have stimulated increased use of these devices without strong evidence or follow-up to assess either efficacy or longer-term clinical outcomes. Current evidence-based guidelines recommend IVC filter insertion only in patients with proven venous thromboembolism and an absolute contraindication for anticoagulation.