A 69-year-old man with non-valvular atrial fibrillation is taking warfarin with a target INR 2.0-3.0. He presents with melaena and haemodynamic instability. INR is 4.5. What is the most appropriate immediate management of his anticoagulation?AContinue warfarin and observeBGive vitamin K orally and continue warfarinCCease warfarin and give IV vitamin K plus prothrombin complex concentrateDCease warfarin and give subcutaneous vitamin K onlyESwitch immediately to a direct oral anticoagulant without reversalCheck my answer