American Society of Hematology 2018 guidelines for management of venous thromboembolism: prophylaxis for hospitalized and nonhospitalized medical patients

Abstract

Background: Venous thromboembolism (VTE) is the third most common vascular disease. Medical inpatients, long-term care residents, persons with minor injuries, and long-distance travelers are at increased risk. Objective: These evidence-based guidelines from the American Society of Hematology (ASH) intend to support patients, clinicians, and others in decisions about preventing VTE in these groups. Methods: ASH formed a multidisciplinary guideline panel balanced to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline-development process, including updating or performing systematic evidence reviews. The panel prioritized clinical questions and outcomes according to their importance for clinicians and adult patients. The Grading of Recommendations Assessment, Development and Evaluation approach was used to assess evidence and make recommendations, which were subject to public comment. Results: The panel agreed on 19 recommendations for acutely ill and critically ill medical inpatients, people in long-term care facilities, outpatients with minor injuries, and long-distance travelers. Conclusions: Strong recommendations included provision of pharmacological VTE prophylaxis in acutely or critically ill inpatients at acceptable bleeding risk, use of mechanical prophylaxis when bleeding risk is unacceptable, against the use of direct oral anticoagulants during hospitalization, and against extending pharmacological prophylaxis after hospital discharge. Conditional recommendations included not to use VTE prophylaxis routinely in long-term care patients or outpatients with minor VTE risk factors. The panel conditionally recommended use of graduated compression stockings or low-molecular-weight heparin in long-distance travelers only if they are at high risk for VTE.

Enoxaparin Thromboprophylaxis Dosing and Anti–Factor Xa Levels in Low‐Weight Patients

“…Our data suggest that use of a lower dose of enoxaparin for VTE prophylaxis may be sufficient to achieve goal peak aFXa levels in low‐weight patients without any demonstration of increased thrombosis risk. The most current ASH guidelines maintain that optimal dosing of parenteral anticoagulation in underweight patients is an area for further research . Despite this, the latest review article recommends enoxaparin 30 mg daily in those with low body weight .…”

“…In low‐weight patients, fixed prophylactic doses of enoxaparin may be close to or even exceed the weight‐based dosing recommended for VTE treatment, which may increase risk for bleeding. The 2018 American Society of Hematology (ASH) guidelines on VTE prophylaxis specifically mention the need for further research regarding the need for dose adjustment in underweight patients …”

What’s new in VTE risk and prevention in orthopedic surgery

“…However, an individual approach is increasingly appealing; its concept is that the individual’s risk of developing VTE (and bleeding) should be assessed and used to guide individual prophylaxis decisions. Ideally, this approach should use validated risk assessment models (RAMs) specific to patients undergoing orthopedic surgery, similar to risk stratification and RAMs recommended by various national and international guidelines for use in hospitalized medical and nonorthopedic surgical patients . An individual approach to prophylaxis would take into account patient risk factors for VTE and bleeding in addition to the surgery itself to help guide prophylaxis decisions.…”

Validation of risk assessment models for venous thrombosis in hospitalized medical patients

“…Of all RAMs, the IMPROVE 7‐factor score comes closest to both a high sensitivity and specificity, which may therefore be preferred. In contrast, the American College of Chest Physicians (ACCP) suggests that the Padua score should be preferred, while the recently published American Society of Hematology 2018 guidelines advice that practitioners should integrate thrombosis and bleeding risk assessments into clinical decision‐making processes . This strengthens the great need for a RAM with high discriminative power and high sensitivity.…”