Thromboembolic prophylaxis in head trauma and multiple-trauma patients

The association between trauma and venous thromboembolism (VTE) is well recognized. VTE consists mainly of deep venous thrombosis (DVT) and pulmonary embolism, a complication that leads to mortality in nearly 50% of cases. Without thromboprophylaxis, the risk of DVT exceeds 50%, but even with routine use of prophylaxis,one third of patients may develop DVT. Despite these findings, appropriate DVT prophylaxis is often not prescribed in trauma patients, mainly because of fear that VTE prophylaxis increases bleeding in injured tissues. Pharmacological VTE prophylaxis is based on the use of low-molecular weight heparins (LMWH). Once-daily or twice-daily LMWH protocols started within 36 h of trauma and continued throughout the hospital stay, or once-daily LMWH followed by a twice-daily protocol are possible options. Mechanical VTE prophylaxis by graduated compression stockings or intermittent pneumatic compression provides suboptimal protection, and its use is recommended only in combination with LMWH prophylaxis unless active bleeding is not controlled. The routine use of VTE prophylaxis in trauma patients is a standard of care. The use of LMWH, started once primary hemostasis has been accomplished, is safe, efficacious and cost-effective in the majority of trauma patients, including TBI patients.     

The role of surveillance duplex scanning in preventing venous thromboembolism in trauma patients

BACKGROUND: This study was performed to determine the role of duplex scanning in preventing pulmonary embolism (PE), the correlation of venous thromboembolism (VTE) risk score with the incidence of deep venous thrombosis (DVT), and patients who may benefit from surveillance duplex scanning. METHODS: Age, sex, Injury Severity Score (ISS), VTE score, length of stay, diagnoses, and bleeding risk were recorded from the trauma registry in patients who had a duplex scan from 1995 to 2000. RESULTS: There were 1,513 duplex scans obtained (10,141 trauma admissions), 253 (2.5%) cases of DVT (52% above-knee, 8% upper extremity), and 30 cases of PE (0.3%). Only 5 of 21 duplex scans were positive in PE patients. DVT patients were older (52.9 vs. 46.7 years), with higher ISS (24.0 vs. 20.8) than patients without DVT. Regression analysis showed poor correlation between VTE score and DVT incidence (r2 = 0.27). Univariate analysis identified age, ISS, and VTE score as risk predictors for DVT. CONCLUSION: Adherence to an evidence-based VTE prophylaxis protocol is more important than surveillance duplex scanning in preventing VTE in trauma patients.     

Equivalence of DOACS and LMWH for thromboprophylaxis after hip fracture surgery: Systematic review and meta-analysis

BackgroundPatients with hip fractures (HF) have an increased risk of venous thromboembolism (VTE). In elective orthopedic surgery direct oral anticoagulants (DOACs) have proven to be similarly or more effective compared to low molecular weight heparin (LMWH), but DOACs are not yet approved for thromboprophylaxis in trauma patients with HF. The aim of this study was to systematically review the literature comparing the effectiveness of DOACs and LMWH for thromboprophylaxis in trauma patients with surgically treated HF.Materials and MethodsWe searched PubMed, the Cochrane Library, Web of Science, and Embase. The primary outcome was the incidence of VTE (symptomatic and asymptomatic combined). Secondary outcomes were symptomatic VTE; a symptomatic VTE, symptomatic deep venous thrombosis (DVT); symptomatic pulmonary embolism (PE); major, clinically relevant non-major (CRNM), and minor bleeding. Meta-analysis was performed to compare the odds of VTE and secondary outcomes between DOACs and LMWH.ResultsThe search resulted in 738 titles. Five studies matched inclusion criteria. In total, 4748 hip fracture patients were analyzed (DOACs: 2276 patients, LMWH: 2472 patients). The pooled odds ratio for the risk of VTE for DOAC use was 0.52 (95% confidence interval 0.25–1.11, p = 0.09) compared to LMWH. No statistically significant differences between DOAC and LMWH were found for asymptomatic VTE, symptomatic DVT, PE, major or CRNM bleeding, and minor bleeding.ConclusionsMeta-analysis of the literature suggests that DOACs are associated with equivalent effectiveness and safety compared to LMWH.     

Dalteparin Vs Low-Dose Unfractionated Heparin for Prophylaxis Against Clinically Evident Venous Thromboembolism in Acute Traumatic Spinal Cord Injury: A Retrospective Cohort Study

Background: When venous thromboembolism (VTE) includes deep-vein thrombosis (DVT) and pulmonary embolism (PE), patients with acute traumatic spinal cord injury (SCI) have the highest incidence of VTE among all hospitalized groups, with PE the third most common cause of death. Although low-molecular-weight heparin (LMWH) outperforms low-dose unfractionated heparin (LDUH) in other patient populations, the evidence in SCI remains less robust.

Objective: To determine whether the efficacy for LMWH shown in previous SCI surveillance studies (eg, routine Doppler ultrasound) would translate into real-world effectiveness in which only clinically evident VTE is investigated (ie, after symptoms or signs present).

Methods: A retrospective cohort study was conducted of 90 patients receiving LMWH dalteparin (5,000 U daily) or LDUH (5,000 U twice daily) for VTE prophylaxis after acute traumatic SCI. The incidence of radiographically confirmed VTE was primarily analyzed, and secondary outcomes included complications of bleeding and heparin-induced thrombocytopenia.

Results: There was no statistically significant association (p = 0.7054) between the incidence of VTE (7.78% overall) and the type of prophylaxis received (LDUH 3/47 vs dalteparin 4/43). There was no significant differences in complications, location of VTE, and incidence of fatal PE. Paraplegia (as opposed to tetraplegia) was the only risk factor identified for VTE.

Conclusions: There continues to be an absence of definitive evidence for dalteparin (or other LMWH) over LDUH as the choice for VTE prophylaxis in patients with SCI. Novel approaches to VTE prophylaxis are urgently required for this population, whose risk of fatal PE has not decreased over the last 25 years.     

Utility of Once-Daily Dose of Low-Molecular-Weight Heparin to Prevent Venous Thromboembolism in Multisystem Trauma Patients

Introduction Venous thromboembolism is a preventable cause of death in the severely injured patient. Low-molecular-weight heparins (LMWHs) have been recommended as effective, safe prophylactic agents. However, LMWH use remains controversial in patients at risk for bleeding, those with traumatic brain injury, and those undergoing multiple invasive or operative procedures. We hypothesized that a protocol utilizing once-daily LMWH prophylaxis in high-risk trauma patients, regardless of the need for invasive procedures, is feasible, safe, and effective. Methods From August 1998 to August 2000, all patients admitted to our American College of Surgeons-verified Level I trauma facility following injury were evaluated for deep venous thrombosis (DVT) risk and prospectively followed. Patients at high risk for DVT, including those with stable intracranial injuries, were placed on our institutional protocol and prospectively followed. Patients on the protocol received daily injections of the LMWH, dalteparin; DVT screening was performed with duplex ultrasonography within 48 hours of admission and after 7 to 10 days after injury. Regimen compliance, bleeding complications, DVT rates, and pulmonary embolus (PE) rates were analyzed. Results During the 2-year study period, 6247 trauma patients were admitted; 743 were considered at high risk for DVT. Most of the patients were men (72%), with a mean age of 38.7 years (range 15–89 years) and a mean injury severity score (ISS) of 19.5. Compliance with the daily regimen was maintained in 74% of patients. DVT was detected in 3.9% and PE in 0.8%. The wound complications rate was 2.7%, and the need for unexplained transfusions was 3%. There were no exacerbations of head injury following dalteparin initiation due to bleeding. There were 16 patient deaths; none was caused by PE or late hemorrhage. Conclusions Once-daily dosing of prophylactic LMWH dalteparin is feasible, safe, and effective in high-risk trauma patients. Our protocol allows one to “operate through” systemic prophylaxis and ensures timely prophylaxis for brain-injured and multisystem trauma patients.     

Prophylaxis against venous thromboembolism in orthopedic surgery

Venous thromboembolism (VTE), which is manifested as deep vein thrombosis (DVT) and pulmonary embolism (PE), represents a significant cause of death, disability, and discomfort. They are frequent complications of various surgical procedures. The aging population and the survival of more severely injured patients may suggest an increasing risk of thromboembolism in the trauma patients. Expanded understanding of the population at risk challenges physicians to carefully examine risk factors for VTE to identify high-risk patients who can benefit from prophylaxis. An accurate knowledge of evidence-based risk factors is important in predicting and preventing postoperative DVT, and can be incorporated into a decision support system for appropriate thromboprophylaxis use. Standard use of DVT prophylaxis in a high-risk trauma population leads to a low incidence of DVT. The incidence of VTE is common in Asia. The evaluation includes laboratory tests, Doppler test and phlebography. Screening Doppler sonography should be performed for surveillance on all critically injured patients to identify DVT. D-Dimer is a useful marker to monitor prophylaxis in trauma surgery patients. The optimal time to start prophylaxis is between 2 hours before and 10 hours after surgery, but the risk of PE continues for several weeks. Thromboprophylaxis includes graduated compression stockings and anticoagulants for prophylaxis. Anticoagulants include Warfarin, which belongs to Vitamin K antagonists, unfractionated heparin, low molecular weight heparins, factor Xa indirect inhibitor Fondaparinux, and the oral IIa inhibitor Melagatran and ximelagatran. Recombinant human soluble thrombomodulin is a new and highly effective antithrombotic agent. Prophylactic placement of vena caval filters in selected trauma patients may decrease the incidence of PE. The indications for prophylactic inferior vena cava filter insertion include prolonged immobilization with multiple injuries, closed head injury, pelvic fracture, spine fracture, multiple long bone fracture, and attending discretion. Multiple-trauma patients are at increased risk for DVT but are also at increased risk of bleeding, and the use of heparin may be contraindicated. Serial compression devices (SCDs) are an alternative for DVT prophylaxis. Compression devices provide adequate DVT prophylaxis with a low failure rate and no device-related complications. Immobilization is one of important reasons of VTE. The ambulant patient is far less Ukely to develop complications of inactivity, not only venous thrombosis, but also contractures, decubitus ulcers, or osteoporosis ( with its associated fatigue fractures), as well as bowel or bladder complications.     

Thromboembolism after trauma: an analysis of 1602 episodes from the American College of Surgeons National Trauma Data Bank

OBJECTIVE: Venous thromboembolic events (VTE) are potentially preventable causes of morbidity and mortality after injury. We hypothesized that the current clinical incidence of VTE is relatively low and that VTE risk factors could be identified. METHODS: We queried the ACS National Trauma Data Bank for episodes of deep venous thrombosis (DVT) and/or pulmonary embolism (PE). We examined demographic data, VTE risk factors, outcomes, and VTE prophylaxis measures in patients admitted to the 131 contributing trauma centers. RESULTS: From a total of 450,375 patients, 1602 (0.36%) had a VTE (998 DVT, 522 PE, 82 both), for an incidence of 0.36%. Ninety percent of patients with VTE had 1 of the 9 risk factors commonly associated with VTE. Six risk factors found to be independently significant in multivariate logistic regression for VTE were age > or = 40 years (odds ratio [OR] 2.01; 95% confidence interval [CI] 1.74 to 2.32), lower extremity fracture with AIS > or = 3 (OR 1.92; 95% CI 1.64 to 2.26), head injury with AIS > or = 3 (OR 1.24; 95% CI 1.05 to 1.46), ventilator days >3 (OR 8.08; 95% CI 6.86 to 9.52), venous injury (OR 3.56; 95% CI 2.22 to 5.72), and a major operative procedure (OR 1.53; 95% CI 1.30 to 1.80). Vena cava filters were placed in 3,883 patients, 86% as PE prophylaxis, including in 410 patients without an identifiable risk factor for VTE. CONCLUSIONS: Patients who need VTE prophylaxis after trauma can be identified based on risk factors. The use of prophylactic vena cava filters should be re-examined.     

Dalteparin versus enoxaparin for venous thromboembolism prophylaxis in acute spinal cord injury and major orthopedic trauma patients: 'DETECT' trial

BACKGROUND: To compare the impact of switching from enoxaparin 30 mg subcutaneously (SC) twice daily to dalteparin 5,000 units SC once daily for venous thromboembolism (VTE) prophylaxis in critically-ill major orthopedic trauma and/or acute spinal cord injury (SCI) patients. METHODS: DETECT was a retrospective, cohort study at a tertiary care referral teaching center-phase 1 from December 1, 2002 to November 30, 2003 (enoxaparin); and phase 2 from January 1, 2004 to December 31, 2004 (dalteparin). Major orthopedic trauma patients with pelvic, femoral shaft, or complex lower extremity fractures, and/or acute SCI patients admitted to the intensive care unit and who received a low-molecular-weight heparin (LMWH) for VTE prophylaxis were included. RESULTS: DETECT reviewed 135 patients (63 enoxaparin, 72 dalteparin), with similar baseline demographics, clinical characteristics, injuries, severity of illness, and risk factors for VTE. Clinically symptomatic proximal deep vein thrombosis (DVT) or pulmonary embolism (PE) rates were 1.6% with enoxaparin and 9.7% with dalteparin (p=0.103, absolute risk increase [ARI] of 8.1% [-0.6% to 15.6%]), with no differences in major bleeding (6.4% versus 6.9%) or minor bleeding (64% versus 69%), or mortality (4.8% versus 6.9%). Switching from enoxaparin to dalteparin was associated with $12,485 (CAD) in LMWH acquisition cost savings. CONCLUSIONS: DETECT raises the hypothesis that dalteparin 5,000 units SC daily may not be clinically noninferior to enoxaparin 30 mg SC twice daily for VTE prophylaxis in this high-risk population. Until an adequately-powered, prospective noninferiority trial is performed, enoxaparin is supported by level 1 evidence and should be the prophylactic agent of choice.     

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

Background:

When venous thromboembolism (VTE) includes deep-vein thrombosis (DVT) and pulmonary embolism (PE), patients with acute traumatic spinal cord injury (SCI) have the highest incidence of VTE among all hospitalized groups, with PE the third most common cause of death. Although low–molecular-weight heparin (LMWH) outperforms low-dose unfractionated heparin (LDUH) in other patient populations, the evidence in SCI remains less robust.

Objective:

To determine whether the efficacy for LMWH shown in previous SCI surveillance studies (eg, routine Doppler ultrasound) would translate into real-world effectiveness in which only clinically evident VTE is investigated (ie, after symptoms or signs present).

Methods:

A retrospective cohort study was conducted of 90 patients receiving LMWH dalteparin (5,000 U daily) or LDUH (5,000 U twice daily) for VTE prophylaxis after acute traumatic SCI. The incidence of radiographically confirmed VTE was primarily analyzed, and secondary outcomes included complications of bleeding and heparin-induced thrombocytopenia.

Results:

There was no statistically significant association (p = 0.7054) between the incidence of VTE (7.78% overall) and the type of prophylaxis received (LDUH 3/47 vs dalteparin 4/43). There was no significant differences in complications, location of VTE, and incidence of fatal PE. Paraplegia (as opposed to tetraplegia) was the only risk factor identified for VTE.

Conclusions:

There continues to be an absence of definitive evidence for dalteparin (or other LMWH) over LDUH as the choice for VTE prophylaxis in patients with SCI. Novel approaches to VTE prophylaxis are urgently required for this population, whose risk of fatal PE has not decreased over the last 25 years.     

A potentially expanded role for enoxaparin in preventing venous thromboembolism in high risk blunt trauma patients

BACKGROUND: Venous thromboembolism (VTE) is a frequent and potentially life-threatening complication after trauma. The purpose of this study is to investigate the effectiveness of enoxaparin in preventing deep venous thrombosis (DVT) and pulmonary embolism (PE) after injury in patients who are at high risk for developing VTE. STUDY DESIGN: A prospective single-cohort observational study was initiated for seriously injured blunt trauma patients admitted to a Level I trauma center during a 7-month period. Patients were eligible for the study if time hospitalized was > or = 72 hours, Injury Severity Score (ISS) was > or = 9, enoxaparin was started within 24 hours after admission, and one or more of the following high risk criteria were met: age > 50 years, ISS > or = 16, presence of a femoral vein catheter, Abbreviated Injury Score (AIS) > or = 3 for any body region, Glasgow Coma Scale (GCS) Score < or = 8, presence of major pelvic, femur, or tibia fracture, and presence of direct blunt mechanism venous injury. Patients with closed head injuries and nonoperatively treated solid abdominal organ injuries were also potential participants. The primary outcomes measured were thromboembolic events--either a documented lower extremity DVT by duplex color-flow doppler ultrasonography or a PE documented by rapid infusion CT pulmonary angiography or conventional pulmonary angiography. RESULTS: There were 118 patients enrolled in the study. Two patients (2%) developed DVT, one of which was proximal to the calf (95% confidence interval, 0% to 6%). Two of 12 patients (17%) with splenic injuries who received enoxaparin failed initial nonoperative management. There were no other bleeding complications, and no clinical evidence or documented episodes of PE. One patient died from multiple system organ failure. CONCLUSIONS: Enoxaparin is a practical and effective method for reducing the incidence of VTE in high risk, seriously injured patients. This study supports further investigation into the safety of enoxaparin prophylaxis in patients with closed head injuries and nonoperatively treated solid abdominal organ injuries.     

Symptomatic venous thromboembolism in Asian major trauma patients: incidence, presentation and risk factors

Background

Trauma patients are known to be at increased risk of venous thromboembolism (VTE), and pulmonary embolism (PE) is one of the preventable causes of mortality in trauma patients. The incidence of VTE in Asian populations was believed to be lower than in Caucasians, but the recent literature suggests that this is not the case. The purpose of this study was to assess the incidence of VTE in Asian major trauma patients and to examine the manner of presentation, use of prophylaxis and risk factors for VTE. While other studies of VTE have addressed general and high-risk populations within Asia, our study is one of the few to examine Asian major trauma patients.

Methods

Data for all patients with VTE were extracted from the Singapore General Hospital trauma database over a 10-year period from 1998 to 2007. Patient profiles and clinical factors were compared to patients without a diagnosis of VTE admitted with injuries in the same time period.

Results

There were 8,615 patients entered into our database in this 10-year period. Thirty-four patients had VTE, with an overall incidence of 0.39 %. Thirteen patients had pulmonary embolism, an incidence of 0.15 %. Of note, 30 % of patients with deep vein thrombosis (DVT) presented with fever alone without limb symptoms. Almost all 34 patients who developed VTE had either head injury, a spinal cord injury or a pelvic/extremity injury. Eighteen patients had head injury, 22 patients sustained pelvic or extremity injury, and three patients had spinal cord injury with paraplegia. Head injury and spinal cord injury with neurologic sequelae were statistically significant risk factors for VTE (p < 0.05).

Conclusion

The incidence of symptomatic VTE in the Asian trauma population is no lower than in the West. The incidence found in this study is similar to the incidence of VTE according to a study using data from the American national trauma data bank using similar study methods and with a similar study population. It is also higher than the incidence in the literature for general post-surgical Asian patients. Fever was the presenting factor in some patients and screening for VTE should not be forgotten when assessing fever in the trauma patient. The strong association between head injury, spinal cord injury and VTE confirms that we should pay special attention to VTE prophylaxis for our patients with these injuries.     

Thrombosis Incidence in Unilateral vs. Simultaneous Bilateral Total Knee Arthroplasty with Compression Device Prophylaxis

This study compares the incidence of venous thromboembolic event (VTE) in 55 patients (110 knees) undergoing simultaneous bilateral TKA with 287 patients (287 knees) undergoing unilateral TKA using a mobile compression device as monotherapy prophylaxis in both groups. All patients were clinically evaluated 3 months after surgery with symptomatic confirmed VTE as an endpoint. Deep venous thrombosis (DVT) was documented by duplex ultrasound and pulmonary embolism (PE) was documented by spiral CT. The simultaneous bilateral TKA group had 6 VTEs (10.9%) with 2 PEs (3.6%). The unilateral TKA group had 9 VTEs (3.1%), and 0 PE. Patients undergoing simultaneous bilateral TKA yielded more than twice the rate of VTE compared with patients undergoing unilateral TKA using a mobile compression device as sole thromboprophylactic modality.     

The survival benefit of low molecular weight heparin over unfractionated heparin in pediatric trauma patients

IntroductionVenous thromboembolism (VTE) prophylaxis in pediatric patients is controversial and is mainly dependent on protocols derived from adult practices. Our study aimed to compare outcomes among pediatric trauma patients who received low molecular weight heparin (LMWH) compared to those who received unfractionated heparin (UFH).MethodsWe performed 2 years (2015–2016) retrospective analysis of the Pediatrics ACS-TQIP database. Pediatric trauma patients (age ≤ 17) who received thromboprophylaxis with either LMWH or UFH were included. Patients were stratified into three age groups. Analysis of each subgroup and the entire cohort was performed. Outcome measures included VTE events (deep vein thrombosis [DVT] and pulmonary embolism [PE]), hospital and ICU length of stay (LOS) among survivors, and mortality. Propensity score matching was used to match the two cohorts LMWH vs UFH.ResultsA matched cohort of 1,678 pediatric trauma patients was analyzed. A significant difference in survival, DVT events, and in-hospital LOS was seen in the age groups above 9 years. Overall, the patients who received LMWH had lower mortality (1.4% vs 3.6%, p < 0.01), DVT (1.7% vs 3.7%, p < 0.01), and hospital LOS among survivors (7 days vs 9 days, p < 0.01) compared to those who received UFH. There was no significant difference in the ICU LOS among survivors and the incidence of PE between the two groups.ConclusionLMWH is associated with increased survival, lower rates of DVT, and decreased hospital LOS compared to UFH among pediatric trauma patients age 10–17 years.Level of EvidenceLevel III Prophylactic.Study TypeProphylactic.     

Chemoprophylaxis for venous thromboembolism in pelvic and/or acetabular fractures: A systematic review

BackgroundIt is unclear which pharmacological agents, and at what dosage and timing, are most effective for venous thromboembolism (VTE) prophylaxis in patients with pelvic/acetabular fractures.MethodsWe searched the Cochrane Database of Systematic Reviews, Embase, Web of Science, EBSCO, and PubMed on October 3, 2020, for English-language studies of VTE prophylaxis in patients with pelvic/acetabular fractures. We applied no date limits. We included studies that compared efficacy of pharmacological agents for VTE prophylaxis, timing of administration of such agents, and/or dosage of such agents. We recorded interventions, sample sizes, and VTE incidence, including deep vein thrombosis (DVT) and pulmonary embolism.ResultsTwo studies (3604 patients) compared pharmacological agents, reporting that patients who received direct oral anticoagulants (DOACs) were less likely to develop DVT than those who received low molecular weight heparin (LMWH) (p < 0.01). Compared with unfractionated heparin (UH), LMWH was associated with lower odds of VTE (odds ratio [OR] = 0.37, 95% confidence interval [CI]: 0.22–0.63) and death (OR = 0.27, 95% CI: 0.10–0.72). Three studies (3107 patients) compared timing of VTE prophylaxis, reporting that late prophylaxis was associated with higher odds of VTE (OR = 1.9, 95% CI: 1.2–3.2) and death (OR = 4.0, 95% CI: 1.5–11) and higher rates of symptomatic DVT (9.2% vs. 2.5%, p = 0.03; and 22% vs. 3.1%, p = 0.01). One study (31 patients) investigated dosage of VTE prophylaxis, reporting that a higher proportion of patients with acetabular fractures were underdosed (23% of patients below range of anti–Factor Xa [aFXa] had acetabular fractures vs. 4.8% of patients within adequate range of aFXa, p<0.01).Conclusions: Early VTE chemoprophylaxis (within 24 or 48 h after injury) was better than late administration in terms of VTE and death. Many patients with acetabular fractures are underdosed with LMWH, with inadequate aFXa levels. Compared with UH, LMWH was associated with lower odds of VTE and death. DOACs were associated with lower risk of DVT compared with LMWH.Level of Evidence: III, systematic review of retrospective cohort studies.     

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.     

A Randomised Open-Label Trial Comparing Long-term Sub-Cutaneous Low-Molecular-weight Heparin Compared with Oral-Anticoagulant Therapy in the Treatment of Deep Venous Thrombosis

ObjectiveTo evaluate whether low-molecular-weight heparin (LMWH) could be equally (or more) effective than oral anti-vitamin-K agents (AVK) in the long-term treatment of deep venous thrombosis (DVT).DesignA randomised, open-label trial.Material and methodsIn this trial, 241 patients with symptomatic proximal DVT of the lower limbs confirmed by duplex ultrasound scan were included. After initial LMWH, patients received 6 months of treatment with full therapeutic dosage of tinzaparin or acenocoumarol. The primary outcome was the 12-month incidence of symptomatic recurrent venous thrombo-embolism (VTE). Duplex scans were performed at 6 and 12 months.ResultsDuring the 12-month period, six patients (5%) of 119 who received LMWH and 13 (10.7%) of 122 who received AVK had recurrent VTE (p = 0.11). In patients with cancer, recurrent VTE tended to be lower in the LMWH group (two of 36 [5.5%]) vs. seven of 33 [21.2%]; p = 0.06). One major bleeding occurred in the LMWH group and three in the AVK group. Venous re-canalisation increased significantly at 6 months (73.1% vs. 47.5%) and at 12 months (91.5% vs. 69.2%) in the LMWH group.ConclusionsTinzaparin was more effective than AVK in achieving re-canalisation of leg thrombi. Long-term tinzaparin was at least as efficacious and safe as AVK for preventing recurrent VTE, especially in patients with cancer.     

Randomized clinical trial of intermittent pneumatic compression and low molecular weight heparin in trauma

BACKGROUND: After trauma, up to 60 per cent of immobilized patients have been reported to develop a silent deep vein thrombosis (DVT). No large, prospective randomized trials have tested the efficacy of intermittent pneumatic compression (IPC) devices in these patients. METHODS: A prospective randomized trial was performed of 442 patients who received thromboprophylaxis using either an IPC device or low molecular weight heparin (LMWH). Duplex imaging was performed on both legs on admission, and was repeated weekly thereafter until discharge, at 30 days or when there was a thrombotic event, whichever occurred first. RESULTS: There were no significant differences in time spent in intensive care, or the proportion of patients with pelvic fractures, spinal cord or head injuries between the two groups. Six patients (2.7 per cent) developed a DVT in the IPC group and one (0.5 per cent) in the LMWH group (P = 0.122). Pulmonary embolism occurred in one patient in each group. There were 13 minor bleeding episodes (four in the IPC group and nine in the LMWH group) and eight major bleeding episodes (four in each group), none of which required operative intervention. CONCLUSION: The low rate of thromboembolic complications and the cost savings suggest that IPC might be used safely and effectively for thromboprophylaxis in trauma patients.     

Is routine thromboprophylaxis justified among Indian patients sustaining major orthopedic trauma? A systematic review

Venous thromboembolism (VTE) is one of the most common preventable cause of morbidity and mortality after trauma. Though most of the western countries have their guidelines for thromboprophylaxis in these patients, India still does not have these. The increasing detection of VTE among Indian population, lack of awareness, underestimation of the risk, and fear of bleeding complications after chemical prophylaxis have made deep vein thrombosis (DVT) a serious problem, hence a standard guideline for thromboprophylaxis after trauma is essential. The present review article discusses the incidence of DVT and role of thromboprophylaxis in Indian patients who have sustained major orthopedic trauma. A thorough search of ‘PubMed’ and ‘Google Scholar’ revealed 10 studies regarding venous thromboembolism in Indian patients after major orthopedic trauma surgery (hip or proximal femur fracture and spine injury). Most of these studies have evaluated venous thromboembolism in patients of arthroplasty and trauma. The incidence, risk factors, diagnosis and management of VTE in the subgroup of trauma patients (1049 patients) were separately evaluated after segregating them from the arthroplasty patients. Except two studies, which were based on spinal injury, all other studies recommended screening/ thromboprophylaxis in posttraumatic conditions in the Indian population. Color Doppler was used as common diagnostic or screening tool in most of the studies (eight studies, 722 patients). The incidence of VTE among thromboprophylaxis-receiving group was found to be 8% (10/125), whereas it was much higher (14.49%, 40/276) in patients not receiving any form of prophylaxis. Indian patients have definite risk of venous thromboembolism after major orthopedic trauma (except spinal injury), and thromboprophylaxis either by chemical or mechanical methods seems to be justified in them.     

Treatment of venous thromboembolism: adherence to guidelines and impact of physician knowledge, attitudes, and beliefs

OBJECTIVES: To assess the treatment of venous thromboembolism (VTE) in hospitalized patients enrolled in a national, multicenter database. METHODS: This was a retrospective, cohort study that randomly selected VTE patients from 38 academic/teaching, community, and Veterans Administration (VA) hospitals. The study included a physician survey component. The patients selected were those treated between January 2002 and June 2003 who had an ICD-9-CM code for pulmonary embolus (PE), deep vein thrombosis (DVT), or pregnancy-related PE or DVT. RESULTS: The study included 939 patients: 52.7% with DVT, 28.4% with PE, and 18.8% with PE and DVT. Mean age was 59.5 years. Risk factors included obesity (body mass index > 30) in 30.1%, history of VTE in 28.0%, malignancy in 27.4%, surgery in 21.1%, and immobility in 18.5%. Only 56.1% of patients were treated with low-molecular-weight heparin (LMWH). Bridging from LMWH or unfractionated heparin (UFH) to warfarin was completed during hospitalization in 486 (68.6%), but only 246 (50.6%) had an international normalized ratio (INR) > or = 2 for 48 hours before discontinuation of the injectable anticoagulant. Length of stay in patients discharged on bridge therapy was 4.0 +/- 3.7 days vs 8.1 +/- 5.8 days for patients discharged on warfarin therapy (P < .001). Ninety-two (10.1%) patients were discharged with neither oral nor injectable anticoagulation and had a mean duration of treatment of only 10.6 +/- 16.2 days. Of 245 physicians surveyed from participating hospitals, 84% and 53%, respectively, indicated that LMWH was their preferred agent for treatment of DVT and treatment of PE. With regard to warfarin, 30% did not believe it was necessary to have a therapeutic INR for > or = 2 days before discontinuing LMWH or UFH, and 27% responded that it was necessary to keep DVT patients in the hospital until they were therapeutic. CONCLUSIONS: In this cross-section of United States hospitals, lower than anticipated use of LMWH, insufficient bridging from UFH or LMWH to warfarin, and continuation of anticoagulation after hospitalization were all problems discovered with the treatment of VTE. Physician knowledge, attitudes, and beliefs are partially responsible for the gap between actual practice and international guidelines. These results suggest that hospitals should evaluate their adherence to international VTE treatment guidelines and develop strategies to optimize antithrombotic therapy.     

多模式预防措施对老年关节置换术后静脉血栓栓塞症发生及转归的影响

目的分析采用多模式血栓预防措施后,老年初次髋、膝关节置换术后静脉血栓栓塞症（VTE）的发生和转归情况。 方法回顾性收集2015年1月至2017年6月行初次单侧髋、膝关节置换的老年患者375例（年龄≥60岁）,所有患者均接受抗凝药物、足底小腿静脉气压泵、加强踝泵和早期下地等康复预防以及减少围手术期脱水等多模式血栓预防措施,术后采用彩色多普勒超声检查双侧下肢深静脉血栓（DVT）的发生情况,对有症状患者行肺动脉CT造影排查肺动脉栓塞（PE）。 结果共349名患者获完整随访,随访率92.5%。随访期间无症状性PE,DVT共38例,总发生率为10.9%,均为远端DVT。手术同侧DVT 38例,双侧3例。症状性DVT共27例（27/38,71.1%）,无症状性DVT 11例（11/38,29.0%）。单纯腓肠肌间静脉血栓29例,单条小腿静脉血栓3例,混合静脉血栓6例。接受不同手术方式的患者DVT发生率差别有统计学意义（χ²=0.000,P<0.001）,其中接受全膝关节置换手术患者DVT的发生率为16.3%,显著高于单髁关节置换手术组的4.7%。单纯腓肠肌间静脉血栓未予药物治疗,其他DVT口服利伐沙班抗凝治疗4 w。术后8 w,有26例（26/38,68.4%）血栓完全消融,12例（12/38,31.6%）血栓未完全消融,但所有DVT相关临床表现均消失,无残留血栓后遗症,且无血栓进展或新发PE。 结论采取多模式预防措施后,老年关节置换术后VTE发生率低,且均为远端DVT,经观察或短程抗凝治疗,症状消失并无后遗症。