What is a typical, reasonable preoperative INR target?

• A. INR <1.0
• B. INR <2.0
• C. INR <2.5
• D. INR <1.5

Answer: (D)

The key idea is balancing bleeding risk with the need to avoid thrombosis when planning surgery for someone on warfarin. For most elective procedures with standard bleeding risk, reducing the anticoagulant effect to an INR below about 1.5 provides a practical compromise: it lowers the chance of surgical bleeding without requiring overly aggressive reversal that could raise thrombosis risk. An INR closer to normal (<1.0) would demand more aggressive reversal and could expose the patient to thromboembolic events if anticoagulation is held longer or bridging is needed. Values higher than 1.5 leave more anticoagulant effect and increase bleeding risk during operation. Therefore, a typical, reasonable preoperative INR target is less than 1.5.