VTE in General/Internal Medicine
A key risk factor for VTE in this group is hospitalization and associated immobility.1,2 Acute medical illness, malignancy, cancer therapy, heart or respiratory failure, inflammatory bowel disease, myocardial infarction, stroke, nephrotic syndrome, infection, recent surgery or trauma, conditions involving paresis, neurologic disease, use of central venous catheter/transvenous pacemaker, and polycythaemia are all patient diseases and conditions which affect risk. In addition, patient characteristics such as increasing age, obesity, thrombophilia, previous VTE, hormone therapy, varicose veins, and pregnancy and the post-partum period are independent risk factors for VTE in these patients.1-3
Risk-assessment of the VTE risks faced by these patients is uncommon. Physicians may perceive these patients, often with numerous active conditions, to be at relatively low risk of VTE-associated morbidity and mortality. However, most hospitalized patients have one or more risk factors for VTE. It has been estimated that around 10–17% of general/internal medicine patients are at risk of VTE.1,4,5
Several well-conducted clinical trials support evidence-based recommendations for more widespread systematic use of thromboprophylaxis in the general/internal medicine patient population. Data from the MEDENOX, PREVENT, and ARTEMIS studies reveal that use of a low-molecular-weight heparin (LMWH) such as enoxaparin or dalteparin, or prophylaxis with fondaparinux results in a consistent 50% reduction in VTE events.4-7 Prophylaxis in these patients is effective and has a good safety profile.
Despite the strong evidence base in favour of VTE prophylaxis in medical patients and a number of clinical guidelines and recommendations to adopt thromboprophylaxis,1,8 in everyday clinical practice many patients do not receive appropriate prophylaxis. A Swiss study suggests 44.9% of acutely ill patients who should have received thromboprophylaxis received no therapy,9 and a recent study in Canada noted that only 16% of medical patients received appropriate prophylaxis.10
Hospitals need to implement tools and strategies to better identify patients at risk of VTE and choose appropriate prophylaxis (drug and regimen) for specific patients if the acute morbidity, substantial consumption of resources, and long-term sequelae of VTE are to be avoided.
- Geerts WH, Pineo GF, et al. Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest. 2004;126 Suppl 3:338S-400S.
- Heit JA, et al. Relative impact of risk factors for deep vein thrombosis and pulmonary embolism: a population-based study. Arch Intern Med. 2002;162:1245-8.
- Samama MM, Dahl OE, et al. Quantification of risk factors for venous thromboembolism: a preliminary study for the development of a risk assessment tool. Haematologica. 2003;88:1410-21.
- Leizorovicz A, Cohen AT, et al. Randomized, placebo-controlled trial of dalteparin for the prevention of venous thromboembolism in acutely ill medical patients. Circulation. 2004;110:874-9.
- Samama MM, Cohen AT, et al. A comparison of enoxaparin with placebo for the prevention of venous thromboembolism in acutely ill medical patients. Prophylaxis in Medical Patients with Enoxaparin Study Group. N Engl J Med. 1999;341:793-800.
- Alikhan R, Cohen AT, et al. Prevention of venous thromboembolism in medical patients with enoxaparin: a subgroup analysis of the MEDENOX study. Blood Coagul Fibrinolysis. 2003;14:341-6.
- Cohen AT, Davidson BL, et al. Efficacy and safety of fondaparinux for the prevention of venous thromboembolism in older acute medical patients: randomised placebo controlled trial. BMJ. 2006;332:325-9.
- Nicolaides AN, Breddin HK, et al. Prevention of venous thromboembolism. International Consensus Statement. Guidelines compiled in accordance with the scientific evidence. Int Angiol. 2001;20:1-37.
- Chopard P, Dorffler-Melly J, et al. Venous thromboembolism prophylaxis in acutely ill medical patients: definite need for improvement. J Intern Med. 2005;257:352-7.
- Kahn SR, Panju A, et al. Multicenter evaluation of the use of venous thromboembolism prophylaxis in acutely ill medical patients in Canada. Thromb Res. 2007;119:145-55.