Anticoagulation: monitoring of patients receiving anticoagulation.

For patients with acute venous thromboembolism treated with warfarin, parenteral anticoagulation should be continued for a minimum of 5 days and until the international normalized ratio (INR) is 2 or greater for at least 24 hours. Early initiation of warfarin therapy is recommended. The goal therapeutic INR range for patients treated with warfarin is most commonly 2 to 3. During maintenance warfarin therapy, validated decision-support tools should be used to guide dosing. For patients with stable INRs, frequency of INR testing can be extended from every 4 weeks to up to 12 weeks. Self-testing and self-management can be safe options for patients receiving warfarin who are motivated and show competence. Patients starting anticoagulation therapy should receive education on treatment goals, adverse effects, and monitoring strategy. Physicians deciding whether to prescribe one of the new oral anticoagulants instead of warfarin should assess for possible drug interactions and for renal and hepatic impairment and should consider the financial cost to the patient. No routine coagulation assay monitoring is required for patients receiving apixaban, dabigatran, or rivaroxaban. Physicians who oversee oral anticoagulation therapy should do so in a systematic and coordinated fashion.