Oral antiocoagulation with warfarin is used to prevent thromboembolic events in patients with atrial fibrillation and prosthetic heart valves, to prevent and treat venous thromobembolism, to treat pulmonary embolism, and to manage hypercoagulable states. In atrial fibrillation, warfarin reduces the annual risk of stroke from 4.5% to 1.4%. However, oral anticoagulants also confer risk for major hemorrhagic complications.

Oral anticoagulation is best carried out by specialized anticoagulation clinics (ACs) that provide efficient, consistent care. AC staff must review new INR (international normalized ratio) results, inform patients of new results, adjust warfarin doses, schedule follow-up appointments, identify missed appointments, and document appropriately. Because over-or underanticoagulation can lead to serious adverse consdquences, these tasks must be carried out meticulously. AC staff may manage up to several hundred patients. Information technology can help assure that routine work is taken care of efficiently and that important events are not overlooked. A model is presented that might be helpful to healthcare organizations considering such technology.