Venous thromboembolism (VTE) affects more than 2 million Americans every year.1 Pulmonary embolism (PE) is one of the most common preventable causes of in-hospital deaths in the United States. Clinical manifestations of PE may be the first indication the patient has a VTE, and fatal PEs occur in at least 75% of hospitalized medical patients. More than 300,000 patients die from PE each year—an estimated incidence of 10%. This makes VTE prevention a top patient-safety goal in hospitals.2,3
Thromboprophylaxis can be accomplished with unfractionated heparin (UFH), low-molecular-weight heparin (LMWH; e.g., enoxaparin, dalteparin, tinzaparin) or heparinoid, or a selective factor Xa inhibitor (e.g., fondaparinux).4 For long-term treatment, oral warfarin is often used. Doses and duration of prophylaxis and treatment regimens vary.
Current guidelines should be reviewed for specific recommendations. Two current guidelines are the American College of Chest Physicians (ACCP) Seventh Conference on the Prevention of VTE and the American Society of Clinical Oncology (ASCO) Guideline for VTE prophylaxis and treatment in oncology patients. Although guidelines are available, thromboprophylaxis continues to baffle many healthcare providers. There are many advantages to thromboprophylaxis including the prevention of significant morbidity, prevention of PE, decreases in resource consumption, and decreases in the long-term clinical and economic sequelae.
The ACCP notes that most surgical patients will require thromboprophylaxis. Contraindications need to be evaluated prior to antithrombotic/anticoagulant use. Additionally, all trauma patients with at least one VTE risk factor should receive thromboprophylaxis. Acutely ill patients hospitalized with congestive heart failure or severe respiratory distress or who are confined to bed and have one or more additional risk factors, should receive VTE prophylaxis. Additionally, most patients upon admission to an intensive-care unit should be assessed for VTE risk and receive thromboprophylaxis as required.
VTE is a major complication in up to 20% of cancer patients, with hospitalized oncology patients and those undergoing treatment at the highest risk. Some of the newer drug treatments used in these patients have higher VTE rates (e.g., bevacizumab, thalidomide, lenalidomide). These patients need to be carefully evaluated for VTE prophylaxis and closely monitored.5
Generally, in hospitalized patients with cancer, VTE prophylaxis should be considered with UFH, LMWH, or fondaparinux, in the absence of bleeding or other contraindications to anticoagulation. Relative contraindications to anticoagulation include (but are not limited to):
- Active uncontrolled bleeding;
- Active cerebrovascular hemorrhage;
- Dissecting or cerebral aneurysm;
- Bacterial endocarditis;
- Active peptic or gastrointestinal ulceration;
- Severe uncontrolled or malignant hypertension;
- Severe head trauma;
- Pregnancy (warfarin contraindication);
- Heparin-induced thrombocytopenia (heparin, LMWH); and
- Epidural catheter placement.
These same contraindications can be applied to the non-oncology patient, as well.
An important aspect of VTE management is the “Clinical Practice Guideline from the American Academy of Family Physicians and the American College of Physicians on the Diagnosis of VTE from the Annals of Family Medicine.” Consult this for a review of diagnostic tests for VTE.
Thromboprophylaxis is a necessity in a number of at-risk hospitalized patients. Knowing which patients will benefit, and the contraindications for use, will improve patient outcomes. Consult current guidelines for diagnosis recommendations as well as agents of choice, dosing regimens, and therapy duration. TH
Michele B. Kaufman is registered pharmacist based in New York City.
- DVT: Assess Your Patients’ Risk, Take Preventive Measures. ASHP Foundation Discoveries, Summer 2007;19(1):1,5. Available at www.ashpfoundation.org/MainMenuCategories/AboutUs/Newsletter/DiscoveriesSummer2007.aspx. Last accessed Nov. 26, 2007.
- Geertz WH, Pineo Graham F, Heit JA et al. Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest. 2004;126:338-400.
- Wein L, Wein S, Haas SJ, et al. Pharmacological venous thromboembolism prophylaxis in hospitalized medical patients, a meta-analysis of randomized controlled trials. Arch Intern Med. 2007;167:1476-1486.
- Lyman GH, Khorana AA, Falanga A, et al. American Society of Clinical Oncology guideline: recommendations for venous thromboembolism prophylaxis and treatment in patients with cancer. J Clin Oncol. 2007;25(34): 5490–5505.
- Qaseem A, Snow V, Barry P for the Joint American Academy of Family Physicians/American College of Physicians Panel on Deep Vein Thrombosis/Pulmonary Embolism. Current diagnosis of venous thromboembolism in primary care: a clinical practice guideline from the American Academy of Family Physicians and the American College of Physicians. Ann Fam Med. 2007;5:57-62.