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Thomas M Hyers

Publications and source records attributed to Thomas M Hyers.

8 recordsLinked to original sources

Compliance with antithrombotic guidelines.

Venous thromboembolism (VTE) remains a significant threat to public health despite the availability of effective and safe prophylactic measures and treatments. Guidelines based on randomized clinical trials are available to improve the management of thromboembolic disease. However, gaps exist between recommendations and clinical practice, and many patients are unnecessarily exposed to the risk of a deep vein thrombosis or potentially fatal pulmonary embolism. Barriers responsible for poor compliance with current antithrombotic guidelines include lack of familiarity with recommendations, overestimation of bleeding risk, underestimation of thrombotic risk, and logistical limitations of health care management systems. Improving compliance is a complex task, but successful initiatives rest upon improving thrombotic risk-assessment methods and facilitating appropriate prescribing of prophylaxis. Multifaceted, interdisciplinary strategies involving risk-assessment models, electronic reminders, and audit and feedback show the most potential to improve compliance with guidelines.

Fibrinolytic Agents↗

Antithrombotic therapy practices in US hospitals in an era of practice guidelines.

BACKGROUND: Antithrombotic therapy is efficacious for the prevention of thromboembolic disease, but it necessitates careful risk-benefit assessment. METHODS: Antithrombotic therapy data were retrospectively collected from inpatient medical records at 38 US hospitals. Patients treated for atrial fibrillation, acute myocardial infarction, deep vein thrombosis, or pulmonary embolism and patients given prophylaxis for total knee replacement, total hip replacement, or hip fracture surgery between July 1, 2000, and June 30, 2003, were randomly selected. RESULTS: The medical records of 3778 patients (53.3% men) were included. The mean patient age was 66.1 years. Of patients with atrial fibrillation at high risk for stroke, only 54.7% received warfarin sodium, and 20.6% received neither aspirin nor warfarin. Of patients with acute myocardial infarction, only 75.5% received aspirin on hospital arrival. After orthopedic surgery procedures, only 85.6% of patients received prophylaxis with a parenteral anticoagulant agent or warfarin. In 49.4% of patients with deep vein thrombosis, pulmonary embolism, or both, unfractionated or low-molecular-weight heparin use was discontinued before an international normalized ratio of 2.0 or greater was achieved for 2 consecutive days. Patients with deep vein thrombosis or pulmonary embolism were rarely discharged from the hospital with bridge therapy (an injectable anticoagulant agent plus warfarin), although the length of hospitalization was significantly shorter than if discharged taking warfarin alone (4.0 vs 8.1 days; P < .001). CONCLUSIONS: A significant percentage of hospitalized patients do not receive adequate antithrombotic therapy for the primary and secondary prevention of thromboembolic disease.

Aged↗

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.

Anticoagulants↗

Heparin and other rapidly acting anticoagulants.

Unfractionated heparin, derived from porcine intestine, is the prototype of a rapidly acting anticoagulant. It has been used for over 60 years to arrest or prevent thrombus growth. Low-molecular-weight heparins, available in the last 20 years, are manufactured from unfractionated heparin and have superior dose-response relationships because of fewer nonspecific reactions with plasma proteins and cells. Fondaparinux is a recently approved five-saccharide synthetic molecule that carries the evolution of heparin further. It is a pure Xa inhibitor, with minimal nonspecific interactions. It does not appear to elicit the antibody that leads to heparin-induced thrombocytopenia (HIT). All of these agents are given either intravenously or subcutaneously. They act indirectly by activating the natural plasma inhibitor, antithrombin III. Direct thrombin inhibitors bind directly to thrombin's active site without interaction with the cofactor, antithrombin III. Lepirudin (Refludan; Berlex, Wayne, NJ) and argatroban (Argatroban; GlaxoSmithKline, Research Triangle Park, NC) are given intravenously and are usually used in HIT and thrombosis associated with HIT. Bivalirudin (Angiomax; The Medicines Company, Parsippany, NJ) is a parenteral direct thrombin used in place of heparin in percutaneous coronary interventions. Ximelagatran (Exanta; AstraZeneca, Wilmington, DE) is an oral direct thrombin inhibitor under development for both acute and chronic anticoagulation.

Anticoagulants↗

Antithrombotic therapy for venous thromboembolic disease: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy.

This chapter about antithrombotic therapy for venous thromboembolic disease is part of the seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy: Evidence Based Guidelines. Grade 1 recommendations are strong and indicate that the benefits do, or do not, outweigh risks, burden, and costs. Grade 2 suggests that individual patients' values may lead to different choices (for a full understanding of the grading see Guyatt et al, CHEST 2004; 126:179S-187S). Among the key recommendations in this chapter are the following: for patients with objectively confirmed deep vein thrombosis (DVT), we recommend short-term treatment with subcutaneous (SC) low molecular weight heparin (LMWH) or, alternatively, IV unfractionated heparin (UFH) [both Grade 1A]. For patients with a high clinical suspicion of DVT, we recommend treatment with anticoagulants while awaiting the outcome of diagnostic tests (Grade 1C+). In acute DVT, we recommend initial treatment with LMWH or UFH for at least 5 days (Grade 1C), initiation of vitamin K antagonist (VKA) together with LMWH or UFH on the first treatment day, and discontinuation of heparin when the international normalized ratio (INR) is stable and > 2.0 (Grade 1A). For the duration and intensity of treatment for acute DVT of the leg, the recommendations include the following: for patients with a first episode of DVT secondary to a transient (reversible) risk factor, we recommend long-term treatment with a VKA for 3 months over treatment for shorter periods (Grade 1A). For patients with a first episode of idiopathic DVT, we recommend treatment with a VKA for at least 6 to 12 months (Grade 1A). We recommend that the dose of VKA be adjusted to maintain a target INR of 2.5 (INR range, 2.0 to 3.0) for all treatment durations (Grade 1A). We recommend against high-intensity VKA therapy (INR range, 3.1 to 4.0) [Grade 1A] and against low-intensity therapy (INR range, 1.5 to 1.9) compared to INR range of 2.0 to 3.0 (Grade 1A). For the prevention of the postthrombotic syndrome, we recommend the use of an elastic compression stocking (Grade 1A). For patients with objectively confirmed nonmassive PE, we recommend acute treatment with SC LMWH or, alternatively, IV UFH (both Grade 1A). For most patients with pulmonary embolism (PE), we recommend clinicians not use systemic thrombolytic therapy (Grade 1A). For the duration and intensity of treatment for PE, the recommendations are similar to those for DVT.

Evidence-Based Medicine↗

Management of venous thromboembolism: past, present, and future.

Venous thromboembolism, including deep vein thrombosis and pulmonary embolism, represents a significant source of morbidity and mortality in the United States and worldwide. The pharmacologic management of venous thromboembolic disease has witnessed significant advances since oral anticoagulant and heparin therapies began to gain widespread use more than 50 years ago. Cumulative clinical experience gained from using these 2 classes of antithrombotic agents for the prevention and treatment of venous thromboembolism in high-risk patients pointed to a number of efficacy and safety limitations. This prompted further research and the eventual introduction, in the 1980s, of low-molecular-weight heparin(s) as a potentially superior therapeutic modality. Within the last decade the pace of development of newer classes of antithrombotic agents for venous thromboembolism prevention and treatment (as well as other indications) has accelerated. Among agents at late stages of investigation are ximelagatran (a direct thrombin inhibitor), nematode anticoagulant peptide c2 (a tissue factor VIIa inhibitor), and sodium N-[8(2-hydroxylbenzoyl)amino]caprylate (SNAC)/heparin (a heparin derivative). The most recently approved agents for venous thromboembolism indications include the heparinoid, danaparoid sodium, and the newly introduced selective factor Xa inhibitor, fondaparinux.

Anticoagulants↗