 - Initially there will be an evaluation of all patients with anticoagulation criteria treated with acenocoumarol or warfarin that present and upper or lower gastrointestinal bleeding. All patients were submit to an initial clinical evaluation including history and physical examination and request a blood test with blood count, biochemistry and coagulation, ECG, chest radiography and abdominal ultrasonography. Anticoagulation be corrected by the administration of vitamin K 10 mg and analytical control are performed at 6 hours to check the reversal of the anticoagulation. 