This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Preoperative assessment and monitoring in anaesthesia, Subject name: Anaesthesia
[{'content': 'Warfarin to be stopped__ days before surgery \nSelect and explain. \nA. 2 to 3 days, B. 4 to 5 days, C. 6 to days, D. 8 to 9 days', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Warfarin should be stopped 4 to 5 days before surgery. clinical implication : to replenish coagulation factors. Monitor PT with INR* , aPTT,ACT. In emergency cases, give Inj.vitamin K., if bleeding continues give FFP,croprecipitate transfusions.', 'role': 'assistant'}]