Four criteria can be used to identify patients with DVT for whom outpatient treatment might not be appropriate: presence of massive DVT, presence of symptomatic pulmonary embolism, high risk of bleeding with anticoagulant therapy, and presence of comorbid conditions or other factors that warrant in-hospital care. This is an extensively studied subject and at this point, limited evidence suggests that home management is cost effective and preferred by patients.
James D. Douketis, Treatment of deep vein thrombosis What factors determine appropriate treatment? Can Fam Physician. 2005 February 10; 51(2): 217–223.
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