Deep vein thrombosis prophylaxis in hospitalized medical patients: current recommendations, general rates of implementation, and initiatives for improvement.

Venous thromboembolism (VTE), which encompasses deep vein thrombosis and pulmonary embolism, is a leading cause of preventable morbidity and mortality following hospitalization. In the last decade, investigators have used randomized controlled trials to assess the efficacy and safety of various methods of VTE prevention for more than 20,000 medical patients. Identifying medical patients at risk for VTE and providing effective prophylaxis is now an important health care priority to reduce the burden of this morbid and sometimes fatal disease.

Patient-level meta-analysis: effect of measurement timing, threshold, and patient age on ability of D-dimer testing to assess recurrence risk after unprovoked venous thromboembolism.

Background: In patients with a first unprovoked venous thromboembolism (VTE), an elevated d-dimer level after anticoagulation is stopped is a risk factor for recurrent VTE. However, questions remain about the utility of measuring d-dimer in clinical practice.

Purpose: To determine whether the timing of testing, patient age, and the cut point used to define a positive or negative result affect the ability of d-dimer testing to distinguish risk for recurrent disease.

Pharmacologic properties of the new oral anticoagulants: a clinician-oriented review with a focus on perioperative management.

The past decade has witnessed an explosion in the clinical development of new orally-administered anticoagulant drugs aimed at complementing vitamin K antagonists and heparins for the prevention and treatment of venous thromboembolism, for the prevention of stroke in patients with chronic atrial fibrillation, and for treatment of acute coronary syndromes. This review will focus on those new oral anticoagulants that are most relevant to the practicing clinician. These drugs consist of dabigatran, a direct thrombin inhibitor and rivaroxaban, a factor Xa inhibitor, both of which have been recently approved for clinical use.

Does the clinical presentation and extent of venous thrombosis predict likelihood and type of recurrence? A patient-level meta-analysis.

Aim: To determine if the mode of presentation of venous thromboembolism (VTE), as deep vein thrombosis (DVT) or pulmonary embolism (PE), predicts the likelihood and type of recurrence.

Methods: We carried out a patient-level meta-analysis of seven prospective studies in patients with a first VTE who were followed after anticoagulation was stopped. We used Kaplan-Meier analysis to determine the cumulative incidence of recurrent VTE according to mode of presentation, and multivariable Cox regression to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for mode of and extent of DVT as potential risk factors for recurrence.

Prevention and treatment of hormone-associated venous thromboembolism: a patient management approach.

Given the known increased risk of venous thromboembolism (VTE) associated with both oral contraceptive (OC) use and hormone replacement therapy (HRT), it is important to address questions about the prevention and management of hormone-associated VTE. Specifically, the objectives of this article are as follows: (1) to provide suggested clinical management approaches for the primary and secondary prevention of VTE for women with thrombophilia; (2) to provide suggested clinical management approaches for the primary and secondary prevention of VTE in the perioperative period for women taking OC or HRT; and (3) to provide practical management approaches for frequently encountered clinical scenarios relating to duration of treatment for hormone-associated VTE.

Safety of uninterrupted anticoagulation in patients requiring elective coronary angiography with or without percutaneous coronary intervention: a systematic review and metaanalysis.

Background: Patients who are receiving vitamin K antagonist (VKA) therapy pose challenges when they require surgery or invasive procedures because the risk for bleeding during the procedure must be balanced against the risk of an atherothrombotic event if the VKA is interrupted. However, it may be possible to safely perform some procedures, such as coronary angiography with or without percutaneous coronary intervention (PCI), without VKA interruption.

Methods: We undertook a systematic review and metaanalysis to assess the safety of a periprocedural management strategy of uninterrupted VKA (U-VKA) vs interrupted VKA (I-VKA) with or without bridging with low-molecular-weight heparin in patients undergoing elective coronary angiography with or without PCI.

The 4Ts scoring system for heparin-induced thrombocytopenia in medical-surgical intensive care unit patients.

Background: Heparin-induced thrombocytopenia (HIT) is commonly considered but rarely confirmed in critically ill patients. The 4Ts score (Thrombocytopenia, Timing of thrombocytopenia, Thrombosis, and oTher reason) might identify individual patients at risk of having this disorder.

Objective: The aim of the study was to evaluate the value of the 4Ts HIT score in comparison with the serotonin-release assay (SRA) in critically ill patients.

Dental surgery for patients on anticoagulant therapy with warfarin: a systematic review and meta-analysis.

Purpose: To evaluate the effect of continuing warfarin therapy on the bleeding risk of patients undergoing elective dental surgical procedures.

Methods: Data sources were the MEDLINE and EMBASE databases, the Cochrane Central Register of Controlled Trials, a manual citation review of the relevant literature, content experts and relevant abstracts from the proceedings of the International Association for Dental Research. Study selection was carried out independently by two reviewers, as was quality assessment.

Risk of deep vein thrombosis following a single negative whole-leg compression ultrasound: a systematic review and meta-analysis.

Context: In patients with suspected lower extremity deep vein thrombosis (DVT), compression ultrasound (CUS) is typically the initial test to confirm or exclude DVT. Patients with an initial negative CUS result often require repeat CUS after 5 to 7 days. Whole-leg CUS may exclude proximal and distal DVT in a single evaluation.

Preventing venous thromboembolism in long-term care residents: Cautious advice based on limited data.

In hospitalized medical patients, randomized trials have established that anticoagulant prophylaxis has an acceptable benefit-to-risk ratio: ie, it lowers the incidence of clinically silent and symptomatic venous thromboembolism (VTE), including fatal pulmonary embolism, more than it raises the risks of bleeding and other complications. However, no similar trials have been done in long-term care residents. More research is needed to ascertain which long-term care residents would benefit most from VTE prophylaxis.

Risk of stroke after surgery in patients with and without chronic atrial fibrillation.

Summary Background: The extent to which chronic atrial fibrillation affects the risk of postoperative stroke is largely unknown.

Objectives: We sought to determine the 30-day rate of stroke among patients with and without chronic AF who underwent 10 different types of surgery.

Patients/methods: The crude incidence of stroke was retrospectively determined using a population-based linked administrative database of hospitalized patients who underwent specified operations between 1 January 1996 and 30 November 2005.

Periprocedural anticoagulation practices in warfarin-treated patients who require elective angiography with or without percutaneous coronary intervention: a retrospective chart review.

Introduction: It may be possible to safely perform some procedures without interrupting warfarin therapy. Coronary angiography with or without percutaneous coronary intervention (PCI) is one such procedure. However, before further high quality research can be performed in this area, information such as current practice and associated event rates is required.

Combined warfarin-aspirin therapy: what is the evidence for benefit and harm and which patients should (and should not) receive it?

Combined warfarin-aspirin therapy is currently used in about 1 million patients in North America for the long-term primary and secondary prevention of atherothrombotic and thromboembolic diseases. Despite a potentially complementary action of anticoagulant and antiplatelet drugs on different components of the thrombotic pathway, their combined use, typically with warfarin and aspirin, is not based in many cases on compelling evidence of a net therapeutic benefit. In the real-world management of patients, clinicians should combine the best available evidence with clinical judgment, considering also that, in most clinical scenarios, clinical practice guidelines may not provide strong or prescriptive recommendations for patients who should (and should not) receive combined aspirin-warfarin therapy.

2009 evidence-based clinical practice guidelines for diagnosing a first episode of lower extremities deep vein thrombosis in ambulatory outpatients.

Introduction: The GRADE working group has recently suggested a rigorous framework for clinical practice guidelines (CPG) addressing diagnostic tests and test strategies based on the impact of alternative approaches on patient-important outcomes. The framework mandates explicit evidence summaries, ratings of the quality of evidence, and specifying recommendations as strong or weak.

Objectives: To test the feasibility and performance of the GRADE approach, we applied this framework to well-researched issues in the diagnoses of deep venous thrombosis (DVT).

Bleeding and venous thromboembolism in the critically ill with emphasis on patients with renal insufficiency.

Purpose Of Review: The purpose of this review is to critique and summarize clinical literature relevant to thromboprophylaxis in critically ill patients with renal insufficiency. The specific objectives are to discuss factors that increase the risks for bleeding and venous thromboembolism in critically ill patients, with a focus on patients with renal insufficiency, and to consider prophylaxis management options and the rationale for their use.

Recent Findings: Herein, we discuss both bleeding and venous thromboembolism in this population, both of which are of concern as complications.

Factors that predict risk of thrombosis in relatives of patients with unprovoked venous thromboembolism.

Background: Factors that predict the risk of venous thromboembolism in the first-degree relatives of patients with unprovoked venous thromboembolism are uncertain but important for counseling. We aimed to identify risk factors for, and quantify the risk of, venous thromboembolism in first-degree relatives of patients (index case patients) with a first episode of unprovoked venous thromboembolism.

Methods: In a cross-sectional study, using a standardized method and without knowledge of whether patients or their relatives had thrombophilia, we assessed the prevalence of previous venous thromboembolism in 1,916 first-degree relatives of 378 unselected patients with a first episode of unprovoked venous thromboembolism.

Thromboprophylaxis for hospitalized medical patients: a multicenter qualitative study.

Background: Observational studies have documented that medical patients infrequently receive venous thromboembolism (VTE) prevention.

Objective: To understand the barriers to, and facilitators of, optimal thromboprophylaxis.

Patients: Hospitalized medical patients.

Event adjudication and data monitoring in an intensive care unit observational study of thromboprophylaxis.

Background: The objective of this report is to describe the roles, responsibilities and recommendations of a 3-member Event Adjudication Committee (EAC) and a 5-member data monitoring committee (DMC) for a prospective multicenter observational study of critically ill patients with renal insufficiency examining the bioaccumulation and bleeding risk associated with dalteparin thromboprophylaxis.

Methods: The EAC reviewed bleeding events to adjudicate whether they were major or minor and whether they were related to dalteparin (uncertain, unlikely, or likely). The DMC reviewed all bleeds deemed by the EAC as uncertain or likely due to dalteparin then recommended either to continue or suspend enrolment pending review by the steering committee, or requested more information.