Probability Of Deep Vein Thrombosis Research Articles

Development and internal validation of a simple clinical score for the estimation of the probability of deep vein thrombosis in outpatient emergency department patients

BackgroundWells score comprises subjective elements, making physicians reluctant to use Wells score or cause them to use it incorrectly. ObjectivesTo develop and internally validate a prediction score that is objective and simple for evaluating suspected deep vein thrombosis (DVT), with a safety comparable with that of Wells score. MethodsWe performed a post hoc analysis using data from the Ri-Schedule study (NCT02486445) involving suspected DVT patients at Østfold Hospital’s Emergency Department, Norway (2015-2018). Candidate variables were identified through bootstrapping technique, with a confirmed DVT diagnosis as the outcome variable. Sensitivity, specificity, negative predictive value (NPV), and positive predictive values (PPV) were estimated and compared with the 2-tier Wells score. ResultsAmong 1312 patients (median age, 64 years [IQR, 52-73]; 55% women), 19.9% were diagnosed with DVT. Exploration of 30 variables identified tenderness along deep veins and previous venous thromboembolism as significant predictors (selection frequency >60% in 1000 bootstrapping samples). The derived score categorized 450 patients with 0 items as unlikely to have DVT, of whom 8.0% were diagnosed with DVT, compared with 8.2% in DVT unlikely category according to Wells score. Compared with Wells score, the derived score demonstrated sensitivity of 86.2 (95% CI, 81.4-90.2) vs 80.1 (95% CI, 74.7-84.8), specificity of 39.4 (95% CI, 36.4-42.4) vs 55.3 (95% CI, 52.2-58.3), NPV of 92.0 (95% CI, 89.4-94.0) vs 91.8 (95% CI, 89.7-93.5), and PPV of 26.1 (95% CI, 24.8-27.5) vs 30.8 (95% CI, 28.9-32.8). When incorporating D-dimer cutoff of <0.5, the derived score had sensitivity of 99.6 (95% CI, 97.9-99.9), specificity of 16.1 (95% CI, 13.1-18.4), NPV of 99.4 (95% CI, 96.0-99.9), and PPV of 22.8 (95% CI, 22.3-23.3). ConclusionThe derived DVT score, with 2 objective variables, had a comparable safety with that of the Wells score. However, an external validation is mandated prior to clinical use.

Correlation between common iliac vein geometry and the risk of deep vein thrombosis in patients with May-Thurner syndrome.

May-Thurner syndrome (MTS) is a continuous pathological change of the left common iliac vein intraluminal wall due to compression between the right common iliac artery and a lumbar vertebra, with clinical signs of compromised venous drainage of the left leg, which eventually leads to development of left-sided deep vein thrombosis (DVT). To analyze the correlation between iliac vessel geometry and probability of DVT in patients with MTS. This study consists of two age-matched female groups: DVT (n = 21) and control (n = 28). Iliac vein geometry, including left common iliac vein (LCIV) diameter, percentage of stenosis, angle between LCIV and right common iliac vein (RCIV), tilt angle of each CIV with horizontal line, and crossing angle between right common iliac artery (RCIA) and LCIV, were measured on computed tomography venography (CTV) images. The probability of DVT development was assessed using logistic regression. Comparing the DVT and control groups, the mean LCIV diameter was 2.4 mm and 3.7 mm (P = 0.001), and mean LCIV stenosis was 77.7% and 68.3% (P = 0.001), respectively. After age-adjustment, the odds of left DVT in patients with MTS correlated with LCIV diameter (odds ratio [OR]=0.25, P < 0.001, 95% confidence interval [CI]=0.11-0.54), LCIV stenosis (%) (OR=1.12, P = 0.003, 95% CI=1.04-1.21), LCIV tilt angle (OR=0.95, P < 0.038, 95% CI=0.91-0.99), and angle between two CIVs (OR=1.04, P < 0.039, 95% CI=1.00-1.09). LCIV diameter and percentage of stenosis, LCIV tilt angle, and CIV angle were independent risk factors for the development of DVT in patients with MTS.

Dynamic observation and risk factors analysis of deep vein thrombosis after hip fracture.

To dynamically observe the occurrence of deep vein thrombosis (DVT) after a hip fracture and analyze of the risk factors affecting the dynamic alteration of DVT. Data of patients with hip fractures from January 1, 2017 to August 31, 2021 were collected. Patients were divided into DVT and non-DVT groups according to their daily Doppler ultrasonography findings. Survival analysis was used to describe dynamic changes in DVT occurrence with time. Log-rank tests were used to compare the influence of individual factors of patients with DVT occurrence, and a Cox proportional hazards regression model was used to identify the risk factors affecting the dynamic alteration of DVT occurrence. A total of 331 patients were included: 148(44.7%) had preoperative DVT, and 143 (96.6%) had DVT in the first 3days after admission. The probability of DVT was 0.42 on Day 1, 0.11 on Day 2, 0.10 on Day 3, 0.08 on Day 4, 0.20 on Day 5, and 0.00 on Day 6-7, with a median survival time of 3.30 d. Age>70 years, intertrochanteric fracture, admission hemoglobin<130g/L, and admission hematocrit<40% had a significantly higher occurrence rate of DVT. A hematocrit level of <40% (Hazard Ratio 2.079, 95% Confidence Interval:1.148-3.764, P = 0.016) was an independent risk factor for DVT. DVT after hip fractures mainly occurred in the first three days after admission, the trend was stabilized within one week, and day 1 had the highest rate of DVT incidence. Age, fracture type, HGB level, and Hct level affected dynamic occurrence of DVT. At constant other factors, Hct<40% was 2.079-fold incidence in the risk of preoperative DVT formation than those with Hct≥40% after hip fracture.

Diagnosis of Deep Vein Thrombosis in Outpatients With Musculoskeletal Disorders: A Survey of Orthopaedic and Sports Academies

PURPOSE: Venous thromboembolism can present as either a deep vein thrombosis (DVT) or a pulmonary embolism. The purpose of this study was to determine if there was a difference in physical therapists' estimation of the probability of a patient having a DVT in patient vignettes as compared with the modified Wells criteria prediction. METHODS: Members of the American Academy of Orthopaedics, Academy of Orthopaedic Physical Therapists (AOPT), and American Academy of Sports Physical Therapy (AASPT) completed patient vignettes. Descriptive statistics were calculated, and sign tests assessed for differences between responses of the presence of DVT (likely or unlikely) and whether referral was necessary. RESULTS: Six hundred and seventy consented, and 521 completed the survey of 24,028 members from the AOPT and AASPT. In total, 7.2% did not feel competent to screen for DVT. Descriptive statistics revealed difficulty in determining whether a DVT was likely or unlikely in 4/5 vignettes as compared with the modified Wells criteria, with only vignette 2 having 95.9% correctly answering as DVT being unlikely. In the other 4 vignettes, approximately 60% to 70% of respondents estimated DVT to be likely, despite 2 of these being unlikely. Across the vignettes, between 2.3% and 19.2% more respondents chose to refer when they determined if a DVT was likely. Across vignettes, statistically significant differences between DVT being likely or unlikely and decision to refer were present. Respondents consistently chose to refer even when a DVT was unlikely (P &lt; .001 for vignettes 1, 3–5. P = .038 for vignette 2). CONCLUSIONS: Venous thromboembolisms are potentially life-threatening conditions seen by physical therapists. Members of the AOPT and AASPT have difficulty in determining the presence or absence of DVT in clinical case vignettes, with some demonstrating a conservative management decision to refer despite low probability of DVT. Efforts to educate members should be considered to improve the understanding of DVT assessment. Clinical Pearls: Members of the AOPT and AASPT appear to have difficulty in determining the presence of a DVT in clinical patient vignettes. Respondents chose to refer patients perhaps with conservative caution. Efforts to educate therapists should be considered to improve the understanding of DVT assessment.

The Relationship of D-dimer Levels and the Incident of Deep Vein Thrombosis in Acute Ischemic Stroke Patients at Haji Adam Malik General Hospital Medan

Background: Deep Vein Thrombosis (DVT) is the formation of a thrombus in deep veins, often observed in stroke patients due to immobilization and infection during hospitalization. High D-dimer levels are associated with DVT in stroke patients. This study aims to evaluate the association between D-dimer levels as a diagnostic tool for DVT in acute ischemic stroke patients. Methods: This cross-sectional, retrospective study was conducted from May to August 2023. The study was carried out on acute ischemic stroke patients at Haji Adam Malik General Hospital, Medan, using consecutive sampling. Doppler ultrasound was used as the gold standard, and D-dimer data were analyzed using the SPSS program, employing the Chi-square test or Fisher's exact test. Results: Of the 49 patients, 35 met the inclusion criteria. Among the patients, 24 (68.6%) were male, 23 (65.7%) were over 50 years old, and 30 (85.7%) had a Body Mass Index (BMI) between 18-24.9. The mean D-dimer value was 2153.43 (±1506.88) ng/mL. All 21 (100%) DVT cases were asymptomatic. According to the Well's score, 15 patients scored 1 (42.8%), 20 patients (57.2%) scored 2, and the probability of DVT is in the moderate range for all 35 patients. The Fisher's Exact Test yielded a p-value of 0.028 (p&lt;0.05). Conclusion: There is a significant relationship between D-dimer levels and the incidence of DVT in patients experiencing acute ischemic stroke. Keywords: Acute Ischemic Stroke, D-dimer, Deep Vein Thrombosis, Doppler Ultrasound

Risk Factors, Diagnosis, Pathophysiology and Management of Deep Vein Thrombosis

Deep vein thrombosis occurs most often in the legs, but can form in the veins of the arms, and in the mesenteric and cerebral veins. Common risk factors of deep vein thrombosis includes age 40 years or older, being overweight, a personal or family history of blood clots, birth control pills, hormone replacement therapy, cancer, certain heart cases, stroke, respiratory failure, varicose veins, pregnancy, surgery including hip, knee, or stomach surgery, restricted mobility due to a long illness, injury, or surgery. Vascular injury that may result from major orthopedic surgery (e.g., knee and hip replacement), trauma (especially fractures of the pelvis, hip, or leg), or indwelling venous catheters. The D-dimer blood test measures degraded fibrinogen, which is raised in patients with a clot. The reference range varies and is set by the laboratory. This test is recommended in patients with a low or moderate clinical probability of deep vein thrombosis, as calculated by the Wells score. The two main types of anticoagulants are heparin and warfarin (coumadin) to keep a clot from growing or prevent new clots from forming. Warfarin interfere with hepatic synthesis of the vitamin K-dependent coagulation factors II, VII, IX and X. Warfarin, a vitamin K antagonist, is an effective and cheap oral anticoagulant.

VENOUS THROMBOEMBOLISM IN THE EMERGENCY DEPARTMENT - SINGLE-CENTER EXPERIENCE.

SUMMARYGiven the importance of early recognition of acute venous thromboembolism (VTE) and the nonspecificity of its symptoms and signs, it is essential to follow the guidelines for diagnostic and therapeutic decisions. Ultrasound examination of the entire lower extremity is currently the standard diagnostic method for symptomatic patients with a clinical probability of deep vein thrombosis (DVT) according to the Wells scoring system. The aim of this study is to show the demographic structure and analyze the number of patients in the emergency department with suspected venous thrombosis. In the past 10 years, 2,022 patients with DVT and 686 with pulmonary emboli have been diagnosed. Despite adherence to the diagnostic protocol, nearly two-thirds of patients require early ultrasound diagnosis. One-fifth of patients had thrombosis of the superficial venous system of the leg or arm. Thrombus was present in the veins of the lower leg in 37% of patients with DVT. The presence of thrombi above the knee, involving the deep femoropopliteal venous system, was found in as much as one-third of patients. These findings and current guidelines suggest that there is a paradigm shift toward more frequent use of DOAC in patients with DVT. However, greater educational efforts may be needed for many physicians to become comfortable with the use of DOAC in the outpatient management of patient populations at low risk for pulmonary embolism.

Diagnostic Value of Neutrophil Lymphocyte Ratio and D-Dimer as Biological Markers of Deep Vein Thrombosis in Patients Presenting with Unilateral Limb Edema.

IntroductionPatients with deep vein thrombosis (DVT) pose high morbidity and mortality risk thus needing fast and accurate diagnosis. Wells clinical prediction scores with D-dimer testing are traditionally used to rule out patients with low probability of DVT. However, D-dimer testing has a few limitations regarding its relatively low specificity. Neutrophil-lymphocyte ratio (NLR), a marker of inflammation, was found to increase in DVT. Hence, we aimed to evaluate the role of NLR for DVT diagnosis.MethodsData were collected from medical records of patients with suspected DVT at Cipto Mangunkusumo National General Hospital during January–December 2014. Diagnosis of DVT was conducted using lower limb ultrasonography. Diagnostic values for NLR, D-dimer, and NLR + D-dimer were determined by receiver operating characteristic (ROC) analysis to obtain area under the curve (AUC), sensitivity, specificity, negative predictive value, and positive predictive values. Sensitivity and specificity analyses of NLR and D-dimer were also conducted based on Wells score and divided into groups of low and high probability of DVT.ResultsThe AUC values for NLR, D-dimer, and NLR + D-dimer were 72.6%, 70.4%, and 76.1%, respectively. The optimal cut-off value determined for NLR was 5.12 with sensitivity of 67.7%, specificity of 67.9%, PPV of 68.85%, and NPV of 64.91% in differentiating subjects with and without DVT. This study also found that D-dimer had sensitivity of 69.4%, specificity of 71.4%, PPV of 72.88%, and NPV of 67.8%. Meanwhile, the NLR + D-dimer combination had sensitivity of 66.1% and specificity of 72.6%. Multivariate analysis showed that NLR (OR: 2.636; 95% CI: 1.144–6.076; p: 0.023) and D-dimer (OR: 4.175; 95% CI: 1.810–9.633; p: 0.001) were associated with DVT.ConclusionNLR value has wider AUC than D-Dimer and is relatively easier to obtain and does not require specific assay, thus enabling rapid evaluation of symptomatic patients suspected of having DVT. Adding NLR to D-dimer increased AUC to detect DVT. Therefore, NLR could serve as a complementary diagnostic tool for D-dimer to exclude DVT, especially in low clinical probability patients.

Diagnostic Accuracy of the Tina-Quant D-Dimer Gen.2 Assay with Age-Adjusted Cut-Off Ranges for Evaluation of Patients with Suspected Deep Vein Thrombosis or Pulmonary Embolism

Introduction: Fibrin degradation products, D-Dimer and X-oligomers, are biomarkers for activation of coagulation. D-Dimer testing is recommended as an additional diagnostic tool for proximal deep vein thrombosis (DVT) and pulmonary embolism (PE), in conjunction with clinical presentation and pre-test probability (Lim, et al. Blood Adv. 2018). D-Dimer levels naturally increase in patients over the age of 50 years, which reduces the specificity of D-Dimer levels as a diagnostic aid for proximal DVT and PE in older patients. We conducted a study to assess the diagnostic accuracy of the Tina-quant® D-Dimer Gen.2 (D-DI2; Roche Diagnostics) assay in patients with a low or intermediate pretest probability for proximal DVT or PE (Bertsch, et al. ISTH 2020; abstract PB0600). An exploratory objective of the study was to evaluate the diagnostic accuracy of the D-DI2 assay in the total study population after applying an age-adjusted cut-off value for patients aged &amp;gt;50 years. Methods: This prospective, observational, multi-center study was conducted between July 2017 and August 2019. Samples were collected at six European hospitals or specialist referral centers, or purchased from a commercial vendor (BioPartners Inc.). The 3.2% citrated plasma samples were analyzed at a central site using the D-DI2 assay on the cobas t 711 analyzer (Roche Diagnostics). Eligible patients were aged ≥18 years, presenting with symptoms suggestive of proximal DVT and/or PE, and with a low or intermediate pretest probability of DVT or PE by Wells score. Main exclusion criteria included DVT and/or PE symptoms for &amp;gt;7 days or a previous diagnosis of DVT and/or PE. DVT and/or PE were diagnosed according to local imaging protocols and standard-of-care procedures, in line with current clinical guidelines. Patients were followed-up for ≥90 days after hospital discharge to verify the clinical diagnosis and record any adverse events. In the primary analysis, a D-DI2 assay cut-off value of 0.5 μg fibrinogen equivalent units (FEU)/mL was applied across all patients, regardless of age. For the purpose of this exploratory analysis, age-adjusted cut-off values were calculated by multiplying age by 0.01 μg FEU/mL for patients aged &amp;gt;50 years. Results: In total, 2516 patients were included in the analysis (1741 DVT cohort; 775 PE cohort); of these, 1538 patients were aged &amp;gt;50 years (996 DVT cohort; 542 PE cohort) and the D-DI2 assay cut-off values for these patients were age-adjusted accordingly. The parameters for diagnostic accuracy for both the DVT and PE cohorts, unadjusted and age-adjusted values, are provided in the Table. Both negative predictive value (NPV) and sensitivity remained high after adjustment for age across both cohorts; however, there were slight decreases compared with the unadjusted values. Positive predictive value (PPV) was increased in both cohorts after age adjustment when compared with the unadjusted values. A reduction in false positives were reported for both the DVT (27%) and PE (26%) cohorts when adjusted for age compared with the unadjusted values. After age-adjustment, the number of false negatives in the total study population increased slightly in the DVT cohort (from zero to one case) and in the PE cohort (from one to five cases). Overall, specificity was increased when the results were adjusted for age. Conclusions: In our study population, when used in conjunction with a low or intermediate pretest probability for DVT and/or PE according to Wells criteria, the D-DI2 assay identifies patients at very low risk for proximal DVT and PE. Adjustment of the cut-off value for age resulted in a slight decrease in NPV, though still below the diagnostic threshold. The benefit of a reduction in false positives observed after age adjustment has the potential to prevent further unnecessary diagnostic procedures for patients. Disclosures Bertsch: Nuremberg General Hospital/Paracelsus Medical University: Current Employment. Blaschke:BMBF: Research Funding; Innovationsfonds: Research Funding; DGINA: Membership on an entity's Board of Directors or advisory committees. Body:University of Manchester: Current Employment; Beckman Coulter: Consultancy; LumiraDx: Consultancy; Roche Diagnostics: Consultancy; Siemens Healthineers: Consultancy; Abbott Point of Care: Consultancy; Abbott Point of Care: Research Funding; Roche Diagnostics: Research Funding; American Association of Clinical Chemistry (sponsored session from Roche, Abbott, ET Healthcare, Ortho, Siemens, Beckman): Speakers Bureau; LumiraDx advisory committee: Membership on an entity's Board of Directors or advisory committees; Creavo (chair of Trial Steering Committee): Membership on an entity's Board of Directors or advisory committees. Davidson:Roche Diagnostics International: Current Employment. Rieger:Roche Diagnostics GmbH: Current Employment. Horner:Salford Royal NHS Foundation Trust: Current Employment. Sonner:Roche Diagnostics GmbH: Consultancy; TRIGA-S Scientific Solutions: Current Employment. Sun:Roche Diagnostics GmbH: Current Employment. Turnes:ICON Clinical Research UK Ltd: Current Employment. Hoffman:Roche Diagnostics GmbH, Germany: Current Employment.

Lower-Extremity Venous Ultrasound in DVT-Unlikely Patients with Positive D-Dimer Test

To review the clinical data, D-dimer level and the ultrasonographic findings from complete venous ultrasound of the lower extremity in deep venous thrombosis (DVT)-unlikely patients with abnormal D-dimer test were compared to DVT-likely patients to ascertain the appropriate ultrasound examination protocol for patients in this group. A retrospective cohort study was conducted of all patients who underwent a complete (whole leg) venous ultrasound in one 13-month period. The medical history, demographic, clinical risk factors, and ultrasonographic findings of the patients with high clinical probability for deep vein thrombosis (Wells score ≥2), along with patients with a low clinical probability of deep vein thrombosis (Wells score ≤1) but with a D-dimer level higher than the threshold (≥500 ng/ml FEU) were evaluated. There were 96 patients in the DVT-likely group and 86 patients in the DVT-unlikely group. The indication for ultrasound examination in the DVT-unlikely group was preoperative assessment to avoid the risk of pulmonary thromboembolism. The patients in the DVT-likely group had more positive ultrasound results for DVT (15.63% vs. 5.18%, p value = 0.03) than the patients in the DVT-unlikely group. In the DVT-unlikely group, the median D-dimer level in the patients with positive ultrasound for DVT showed statistically significantly higher levels than the patients with negative ultrasound for DVT did (2208 vs. 921 ng/ml FEU, p value = 0.02). The optimal D-dimer cut-off from the receiver operating characteristics analysis shows the maximized summation of sensitivity and specificity (80% and 66.67%) at 1251 ng/ml FEU. The prevalence of acute thrombus in a thigh vein in DVT-unlikely, preoperative patients is low (1.2%). To minimize the number of unnecessary complete venous ultrasound lower-extremity examinations, the use of a higher D-dimer cut-off level and limiting proximal or thigh vein ultrasound examinations in the preoperative patient is considered.

The Effects of Multi-Slice Helical Computed Tomography and Phlebography on Edema Regression Nursing of Lower Limbs Varicosis

Objective: To explore the effects of multi-slice helical computed tomography (MSCT) and phlebography on edema regression nursing of lower limbs varicosis, and to analyze the values of MSCT and phlebography on the diagnosis and treatment of lower limb varicosis. Methods: A total of 193 patients with lower limb varicosis treated in the Vascular Surgery Department were included as the research objects. According to different examination methods, the included patients were divided into the MSCT group, and the MSCT combined with the phlebography group, Then, patients in both groups received joint treatment of high ligation and varicectomy. The Gabor filtering-based algorithm and the Mean-Variance Efficient Frontier (MVEF) algorithm were used to smoothen the obtained images. Also, the operation rates and contradiction compositions of patients in both groups were analyzed. Patients who received surgical treatment were followed up for three months to one year; whether the deep vein thrombosis (DVT) occurred in them were observed, as well as the edema regression. Results: As for gender, grading, disease history, duration of disease, and onset age of both groups, no statistical significance was found (P &gt; 0.05). Compared to group A, the positive detection rate of postoperative DVT was lower in group B, so did the operation rate. In group A, 32 cases of edema regressed significantly, and the disease condition was relieved. In group B, 35 cases of edema were regressed. Conclusion: Compared with MSCT, phlebography had a higher screening rate for indications of lower limb varicosis, which could effectively reduce the probability of DVT after operations and relieve the symptoms of edema in patients. In addition, although the sensitivity of MSCT was relatively low, it could be used for the primary screening diagnosis of lower limb varicosis.

Deep vein thrombosis: update on diagnosis and management.

Diagnosis of deep vein thrombosis (DVT) requires a multifaceted approach that includes clinical assessment, evaluation of pre-test probability, and objective diagnostic testing. Common symptoms and signs of DVT are pain, swelling, erythema and dilated veins in the affected limb. The pre-test probability of DVT can be assessed using a clinical decision rule that stratifies DVT into "unlikely" or "likely". If DVT is "unlikely", refer for D-dimer test. If the D-dimer level is normal, DVT can be excluded; if the D-dimer level is increased, refer for compression ultrasound. If DVT is "likely", refer for compression ultrasound. When DVT is confirmed, anticoagulation is indicated to control symptoms, prevent progression and reduce the risk of post-thrombotic syndrome and pulmonary embolism. Anticoagulation may consist of a parenteral anticoagulant overlapped by warfarin or followed by a direct oral anticoagulant (DOAC) (dabigatran or edoxaban), or of a DOAC (apixaban or rivaroxaban) without initial parenteral therapy. DOACs are the preferred treatment for DVT because they are at least as effective, safer and more convenient than warfarin. DOACs may require dose reduction or avoidance in patients with renal dysfunction, and should be avoided in pregnancy. Recent evidence shows that DVT in patients with cancer may be treated with edoxaban (after discontinuation of 5 days of initial heparin or low molecular weight heparin [LMWH]) or rivaroxaban if patients prefer not to have daily injections of LMWH, but the risk of gastrointestinal bleeding is higher with DOACs than with LMWH in patients with gastrointestinal cancer.

Stratification of deep vein thrombosis and pulmonary embolism risk factors after trauma and orthopedic surgery

The aim of this work is to assess the methods of risk stratification of deep vein thrombosis (DVT) and pulmonary embolism (PE) after trauma and orthopedic surgery. Modern data devoted to risk factors of DVT and PE (including genetic) are uncertaint. We analyzed probability of DVT and PE on the base of literature data for trauma and orthopedic patients. Different models of risk stratification being compared. Single gene mutation is not sig-nificant for DVT risk prediction. Correlations between several gene mutations and polymorphism increase probability of proper risk estimation. Programmatic DVT and HAS risk estimation calculator developed and is accessible on web-site.

An Unusual Presentation of Deep Vein Thrombosis.

May–Thurner syndrome (MTS) usually presents as acute or chronic deep vein thrombosis (DVT) in patients. A 49-year-old woman presented with left lower limb DVT, which was followed by a diagnosis of MTS on a background of polycystic ovary syndrome (PCOS) and hypothyroidism. MTS is more common among women in the second to fourth decades of life. An endovascular approach is the preferred first-line treatment for MTS.LEARNING POINTSThis case highlights the importance of serial ultrasound Doppler scans in cases where the probability of deep vein thrombosis (DVT) is high as a negative initial Doppler scan does not exclude DVT.May–Thurner syndrome (MTS) should be suspected especially in younger patients in whom no cause for DVT has been found.Missing a diagnosis of MTS could result in life-threatening conditions such as pulmonary embolism and post-thrombotic syndrome.

Are Revision Hip Arthroplasty Patients at Higher Risk for Venous Thromboembolic Events Than Primary Hip Arthroplasty Patients?

BackgroundThe purpose of this study is to determine whether revision total hip arthroplasty (THA) is associated with increased rates of deep vein thrombosis (DVT) and pulmonary embolism (PE) when compared to primary THA. MethodsWe queried the American College of Surgeons National Surgical Quality Improvement Program database for all primary and revision THA cases from 2011 to 2014. Demographic data, medical comorbidities, and venous thromboembolic rates within 30 days of surgery were compared between the primary and revision THA groups. ResultsRevision THA had a higher rate of DVT than the primary THA (0.6% vs 0.4%, P = .016), but there was no difference in the rate of PE (0.3% vs 0.2%, P = .116). When controlling for confounding variables, revision surgery alone was not a risk factor for DVT (odds ratio 0.833, 95% confidence interval 0.564-1.232) or PE (odds ratio 1.009, 95% confidence interval 0.630-1.616). Independent risk factors for DVT include age >70 years, malnutrition, infection, operating time >3 hours, general anesthesia, American Society of Anesthesiologists classification 4 or greater, and kidney disease (all P < .05). Probability of DVT ranged from 0.2% with zero risk factors to 10% with all risk factors. Independent risk factors for PE included age >70 years, African American ethnicity, and operating time >3 hours (all P < .05) with probabilities of PE postoperatively ranging from 0.2% to 1.1% with all risk factors. ConclusionRevision surgery alone is not a risk factor for venous thromboembolism after hip arthroplasty. Surgeons should weigh the risks and benefits of more aggressive anticoagulation in certain high-risk patients.

Seasonal variations in the incidence of deep vein thrombosis following total knee or hip arthroplasty

Objective To explore the difference in the incidence of deep vein thrombosis (DVT) following total knee arthroplasty (TKA) or total hip arthroplasty (THA) between different seasons. Methods The present retrospective study examined 2 363 patients undergoing TKA or THA from August 2008 to February 2016. There were 653 male and 1 710 female with the average age of 64.44±13.03 years old (17-91 years old), including 954 patients in TKA and 1 409 in THA. All of the patients received anticoagulant drugs and were compressed with a pressure pump starting on the first postoperative night. Routine venography of the bilateral lower limbs was performed at 3-5 days after the operation. The incidence of DVT in different seasons and different age groups (≥65 years old and <65 years old) were counted. Results The present study suggested that the probabilities of DVT after arthroplasty in spring, summer, fall and winter were 15.85% (116/732), 14.92% (71/476), 17.88% (108/604), 22.50% (124/551) respectively with significantly difference (P 0.05). The probability of DVT following arthroplasty in older patients (age≥65 years old) in spring, summer, fall and winter were 18.49% (76/411), 16.61% (45/271), 22.07% (81/367), 28.05% (99/353) with significantly difference among the groups (P 0.05). The probability of symptomatic DVT in four seasons were 2.49% (8/321), 2.93% (6/205), 3.80% (9/237), 3.54% (7/198) in younger patients ( 0.05). Conclusion Seasonal variations could place an important effect on the incidence of DVT following TKA or THA, especially for the old patients with age ≥65 years. Key words: Arthroplasty, replacement, knee; Arthroplasty, replacement, hip; Seasons; Venous thrombosis; Lower extremity

Test Characteristics of Emergency Physician−Performed Limited Compression Ultrasound for Lower-Extremity Deep Vein Thrombosis

BackgroundThe current literature suggests that emergency physician (EP)−performed limited compression ultrasound (LCUS) is a rapid and accurate test for deep vein thrombosis (DVT). ObjectiveOur primary objective was to determine the sensitivity and specificity of LCUS for the diagnosis of DVT when performed by a large heterogeneous group of EPs. MethodsThis was a prospective diagnostic test assessment of LCUS conducted at two urban academic emergency departments. The scanning protocol involved compression at the common femoral, superficial femoral, and popliteal veins. Patients were eligible if undergoing radiology department ultrasound of the lower extremity with moderate or high pretest probability for DVT, or low pretest probability for DVT with a positive d-dimer. The enrolling EP performed LCUS before radiology department ultrasound of the same lower extremity. Sensitivity, specificity, and associated 95% confidence intervals (CIs) were calculated with the radiologist interpretation of the radiology department ultrasound as the criterion standard. ResultsA total of 56 EPs enrolled 296 patients for LCUS, with a median age of 50 years and 50% female. Fifty (17%) DVTs were identified by radiology department ultrasound, and another five (2%) cases were deemed indeterminate. The sensitivity and specificity of EP-performed LCUS was 86% (95% CI 73−94%) and 93% (95% CI 89−96%), respectively. ConclusionsA large heterogeneous group of EPs with limited training can perform LCUS with intermediate diagnostic accuracy. Unfortunately, LCUS performed by EPs with limited ultrasound training is not sufficiently sensitive or specific to rule out or diagnose DVT as a single testing modality.

Left lower limb may be a forbidden region for indwelling needle during operation

IntroductionInformation about the incidence and risk factors of venous thromboembolism (VTE) after thyroid operation is limited. This study aimed to analyze the incidence and risk factors of postoperative VTE in patients who had undergone thyroid surgery. Materials and methodsA prospective, multi-center cohort study was performed from June 2013 to June 2015 in 3 hospitals throughout South Central China. We analyzed 5029 patients who had undergone thyroid operation and received no VTE prophylaxis postoperatively. For the diagnosis of deep vein thrombosis (DVT), bilateral whole-leg ultrasound was conducted in patients with a high pretest probability of DVT. Lung ventilation/perfusion scintigraphy, pulmonary angiography, or helical computed tomography was implemented in patients suspected to have pulmonary embolism (PE). ResultsDVT was diagnosed in 18 patients (0.36%). No patient was diagnosed with PE. Binomial logistic regression analysis revealed that age and left lower limb intraoperative venous access (IVA) were significant risk factors for DVT. The incidence of DVT increased as the number of risk factors increased. ConclusionsVTE is uncommon in patients who have undergone thyroid surgery. The left lower limb was not an appropriate insertion site IVA. Pharmacologic thromboprophylaxis was not mandatory, particularly in those patients without risk factors.

A clinical score to rule out the concomitant presence of deep vein thrombosis in patients presenting with superficial vein thrombosis: The ICARO study

BackgroundSuperficial vein thrombosis (SVT) is commonly encountered in clinical practice. Recent studies have suggested that the concomitant presence of deep vein thrombosis (DVT) or pulmonary embolism (PE) at the time of SVT diagnosis is not uncommon, thus increasing the interest on this disease. Whether this coexistence is predicted by specific risk factors remains unknown. Aim of the studyTo evaluate potential risk factors for DVT coexistence in patients presenting with acute objectively diagnosed SVT of the lower limbs and to develop a simple score entirely based on clinical variables to define the pre-test probability of DVT in these patients. MethodsA multicenter, retrospective cohort study on SVT patients was conducted. Information was collected on clinical signs and on risk factors for venous thrombosis. Results494 patients (mean age 56.3±17.9years, 64.2% women) were included. Concomitant DVT was found in 16.0% of patients. After multivariate analysis, we identified 5 independent variables that were used to develop the ICARO score: active malignancy (1.5 points), limb edema (1.5 points), rope-like sign (−1 point), age≥50years (1 point), unprovoked SVT (−1 point). The prevalence of concomitant DVT was 1.1% in the low-probability category (<0 points), 12.0% in the intermediate-probability category (0 to 1 points), and 32.3% in the high probability category (≥1.5 points). ConclusionsThe concomitant presence of major DVT is not negligible in patients with SVT. Our prediction score entirely based on simple clinical variables may be useful in assessing the risk of concomitant DVT in these patients.

Analysis of the accuracy of the Wells scale in assessing the probability of lower limb deep vein thrombosis in primary care patients practice.

BackgroundThe clinical picture of deep vein thrombosis (DVT) is nonspecific. Therefore assessment of the probability of occurrence of DVT plays a very important part in making a correct diagnosis of DVT.The aim of our prospective study was to assess the accuracy of the Wells scale in primary care setting in diagnostic procedure of suspected deep vein thrombosis.MethodsIn the period of 20 - months (from 2007 to 2009) a group of residents from one of the urban districts of Warsaw, who reported to family doctors (22 primary care physicians were involved in the study) with symptoms of DVT were assessed on the probability of occurrence of deep vein thrombosis using the Wells scale. Family doctors were aware of symptoms of DVT and inclusion patients to this study was based on clinical suspicion of DVT.Patients were divided into three groups, reflecting probability of DVT of the lower limbs.To confirm DVT a compression ultrasound (CUS) test was established.We analyzed the relationship between a qualitative variable and a variable defined on an original scale (incidence of DVT versus Wells scale count) using the Mann–Whitney test. Chi-square test compared rates of DVT events in all clinical probability groups.Patient were follow up during 3 months in primary care setting.ResultsIn the period of 20 months (from 2007 to 2009) a total number of 1048 patients (male: 250 , female: 798 mean age: 61.4) with symptoms suggestive of DVT of the lower extremities entered the study. Among the 100 patients classified in the group with a high probability of DVT of the lower extremities, 40 (40%) patients (proximal DVT - 13; distal DVT - 27) were diagnosed with it (95% CI [30.94% -49.80%]). In the group with a moderate probability consisting of 302 patients, DVT of the lower extremities was diagnosed in 19 (6.29%) patients (95% CI [4.06% -9.62%]), (proximal DVT – 1; distal DVT - 18). Of the 646 patients with a low probability of DVT of the lower extremities distal DVT was diagnosed in 1 (0.15%) patient (95% CI [0.03% -0.87%]).ConclusionThe Wells scale used in primary care setting demonstrated a high degree of accuracy.