Use Of Compression Ultrasonography Research Articles

Practice Variations in the Diagnosis and Treatment of Pulmonary Embolism.

Venous thromboembolism is responsible for a significant burden of disease worldwide. Despite the publication of multiple international guidelines, anecdotal evidence suggests significant clinical variation exists in the diagnostic and management pathways of pulmonary embolism (PE). We conducted a retrospective cohort study using electronic medical records to examine clinical variation in patients admitted to a tertiary referral center in Australia with a diagnosis of PE between November 2018 and January 2020. Three hundred cases met the inclusion criteria; we found variation in rates of compression ultrasonography, acute investigation of the right ventricle, and planning of repeat imaging at specialist follow-up. Guidelines do not address the use of compression ultrasonography in already diagnosed PE, are conflicting in their recommendation for acute investigation of the right ventricle, and recommend repeat imaging only if there are persistent symptoms at the time of specialist follow-up. The variations we found in this study may in part be due to physician preference or due to the paucity of evidence for some of these diagnostic practices. Robust future studies are required to guide the use of these investigations in PE.

Residual vein obstruction to predict the risk of recurrent venous thromboembolism in patients with deep vein thrombosis: a systematic review and meta‐analysis

Residual vein obstruction (RVO) detected on compression ultrasonography of the leg after a few months of anticoagulation therapy might be able to identify patients with deep vein thrombosis (DVT) at high risk of having a recurrent venous thromboembolism (VTE). To determine whether RVO is associated with an increased risk of recurrent events in patients with DVT. A systematic literature search strategy was conducted using MEDLINE, EMBASE, and the Cochrane Register of Controlled Trials. We selected 14 articles (nine prospective cohort studies and five randomized controlled trials) that included patients with DVT who had an assessment for RVO with the use of compression ultrasonography. Two reviewers independently extracted data onto standardized forms. Overall, the presence of RVO was not associated with an increased risk of recurrent VTE (odds ratio [OR] 1.24, 95% confidence interval [CI] 0.9-1.7) in patients with unprovoked DVT who stopped oral anticoagulation therapy at the time of RVO assessment. However, RVO was significantly associated with recurrent VTE in patients with any (unprovoked or provoked) DVT (OR 1.5, 95% CI 1.1-2.0). RVO was associated with a modestly increased risk of recurrent VTE in patients with DVT (unprovoked and provoked). However, RVO did not seem to be a predictor of recurrent VTE in patients with unprovoked DVT following anticoagulation discontinuation. Further prospective studies are needed to assess the role of RVO in patients with unprovoked DVT.

Cost-effectiveness of Lower Extremity Compression Ultrasound in Emergency Department Patients With a High Risk of Hemodynamically Stable Pulmonary Embolism

Computed tomography angiograms (CTAs) for patients with suspected pulmonary embolism (PE) are being ordered with increasing frequency from the emergency department (ED). Strategies are needed to safely decrease the utilization of CTs to control rising health care costs and minimize the associated risks of anaphylaxis, contrast-induced nephropathy, and radiation-induced carcinogenesis. The use of compression ultrasonography (US) to identify deep vein thromboses (DVTs) in hemodynamically stable patients with signs and symptoms suggestive of PE is highly specific for the diagnosis of PE and may represent a cost-effective alternative to CT imaging. The objective was to analyze the cost-effectiveness of a selective CT strategy incorporating the use of compression US to diagnose and treat DVT in patients with a high pretest probability of PE. The authors constructed a decision analytic model to evaluate the scenario of an otherwise healthy 59-year-old female in whom PE was being considered as a diagnosis. Two strategies were used. The selective CT strategy began with a screening compression US. Negative studies were followed up with a CTA, while patients with positive studies identifying a DVT were treated as though they had a PE and were anticoagulated. The universal CT strategy used CTA as the initial test, and anticoagulation was based on the CT result. Costs were estimated from the 2009 Medicare data for hospital reimbursement, and professional fees were obtained from the 2009 National Physician Fee Schedule. Clinical probabilities were obtained from existing published data, and sensitivity analyses were performed across plausible ranges for all clinical variables. In the base case, the selective CT strategy cost $1,457.70 less than the universal CT strategy and resulted in a gain of 0.0213 quality-adjusted life-years (QALYs). Sensitivity analyses confirm that the selective CT strategy is dominant above both a pretest probability for PE of 8.3% and a compression US specificity of 87.4%. A selective CT strategy using compression US is cost-effective for patients provided they have a high pretest probability of PE. This may reduce the need for, and decrease the adverse events associated with, CTAs.

217: Cost-Effectiveness of Lower Extremity Compression Ultrasonography In Emergency Department Patients With a High Risk of Non-Massive Pulmonary Embolism

Computed tomography (CT) angiograms for patients with suspected pulmonary embolism (PE) are being ordered with increasing frequency from the emergency department. Strategies are needed to safely decrease the utilization of CTs in order to control rising health care costs and minimize the associated risks of contrast-induced nephropathy (CIN) and radiation-induced carcinogenesis (RIC). The use of compression ultrasonography (CUS) to identify deep venous thromboses (DVTs) in hemodynamically stable patients with signs and symptoms suggestive of PE is highly specific for the diagnosis of PE and may represent a cost-effective alternative to CT imaging.

Predicting Deep Venous Thrombosis in Pregnancy: Out in “LEFt” Field?

In the nonpregnant general population, deep venous thrombosis (DVT) can be excluded at the initial presentation not only by clinical assessment and review of risk factors, but also by the clinician's assessment of probability using subjective criteria or prediction rules. Because of the absence of a validated prediction rule for diagnosing DVT during pregnancy, diagnosis in pregnant patients depends largely on the use of compression ultrasonography, the diagnostic reference standard that establishes the presence or absence of DVT. The aim of this cross-sectional study was to investigate the predictive accuracy of clinicians' subjective assessment of the probability of DVT in women with suspected DVT and to identify useful objective prediction variables. The participants were 194 unselected pregnant women with suspected first DVT. Potential study patients were identified by clinicians during the initial examination when the clinical assessment was consistent with DVT, and led to consultation with thrombosis experts who obtained informed consent for participation in the study. Before compression ultrasonography testing, the experts examined each study patient and categorized their pretest probability of DVT based on subjective criteria as low, moderate, or high. The sensitivity, specificity, negative predictive value, and likelihood ratios of the clinicians' subjective pretest probability were calculated. Patients defined as DVT positive had abnormal diagnostic compression ultrasonography results at the initial presentation or during serial testing, or had symptomatic DVT or pulmonary embolism on follow-up. Patients with negative compression ultrasonography at presentation and no venous thromboembolism on follow-up were defined as DVT negative. DVT was diagnosed in 17 women (8.8%). The prevalence of DVT in patients with low pretest probability (two-third of patients) was 1.5% (2/131), with a 95% confidence interval of 0.4% to 5.4% (P < 0.001). The prevalence among those with moderate or high pretest probability was considerably higher, 24.6% (15/61), with a 95% confidence interval of 15.5% to 36.7% (P < 0.001). Multivariate analysis identified 3 independent variables that were highly predictive of DVT in pregnant women: left leg symptoms, difference in calf circumference of 2 cm or more, and presentation during the first trimester of pregnancy. DVT was unlikely in the absence of all 3 variables, and its probability increased substantially if 1 or more was present. These findings demonstrate that probability of DVT in pregnant women with suspected DVT may be assessed with use of 3 easily determined objective variables. The data show that DVT is very unlikely with a very low pretest probability.

Is antithrombotic prophylaxis required in cancer patients with central venous catheters? Yes for special patient groups.

Is antithrombotic prophylaxis required in cancer patients with central venous catheters? Yes for special patient groups.

THE DIAGNOSIS OF LOWER EXTREMITY DEEP VENOUS THROBOSIS

The diagnosis of lower extremity deep venous thrombosis (DVT) is critical to emergency physicians because of the risk of pulmonary embolism. This article reviews the diagnostic modalities available for patients with suspected lower extremity DVT. The use of compression ultrasonography and the recent advances in the D-dimer assays are emphasized. A clinical algorithm that utilizes a non invasive approach to this potentially life threatening disease is presented.

Looking for deep vein thrombosis in suspected pulmonary embolism.

Pulmonary embolism (PE) and deep vein thrombosis are two facets of the same disease, that is, venous thromboembolism (VTE). In patients with angiographically proven PE, the prevalence of proximal deep vein thrombosis by venography is around 70%. The sensitivity of compression ultrasonography (US) for the diagnosis of acute VTE in patients with a suspicion of PE is between 40 and 60%, with a high specificity (96 to 100%). Taking into account the 20 to 30% prevalence of PE in a population consulting for suspicion of this disease, the first line use of compression US will allow the diagnosis of acute VTE in half of patients with confirmed PE, that is, in 10 to 15% of patients addressed for suspicion of PE. In outpatients, the first line use of D-dimers which will exclude acute VTE in one-third of the initial population will slightly increase the reliability of compression US as a first imaging test. New tools of looking for deep vein thrombosis, such as computed tomographic venography coupled with computed tomographic pulmonary angiography, could become an interesting approach in the diagnostic strategy of PE, but require adequate evaluation in prospective studies.

Optimal management strategy for use of compression US for deep venous thrombosis in symptomatic patients: A cost-effectiveness analysis

The authors' purpose was to identify the optimal strategy for using compression ultrasonography (US) in patients suspected of having deep venous thrombosis (DVT). The authors developed a decision-analytic model representing the natural history of DVT and the benefits and risks of anticoagulation therapy. They evaluated six initial imaging strategies: (a) unilateral examination of the common femoral and popliteal veins; (b) unilateral examination of the common femoral, popliteal, and femoral veins; (c) bilateral examination of the common femoral and popliteal veins; (d) bilateral examination of the common femoral, popliteal, and femoral veins; (e) complete unilateral examination of the symptomatic leg (including calf veins); and (f) complete bilateral examination of both legs. For 65-year-old men with unilateral symptoms of DVT, the most effective strategy was bilateral examination of the common femoral and popliteal veins with anticoagulation therapy in patients with proximal DVT and follow-up bilateral examination of the common femoral and popliteal veins in patients without an initial diagnosis of DVT with an incremental cost-effectiveness ratio of $39,000 per quality-adjusted life year gained. These results suggest that bilateral examination limited to the common femoral and popliteal veins, with follow-up bilateral examination limited to the common femoral and popliteal veins, was as cost-effective as other well-accepted medical interventions. The results were sensitive to the distribution of clot, diagnostic accuracy of compression US, and probability of bleeding with long-term morbidity.