An elderly patient taking warfarin for atrial fibrillation experiences a fall, leading to a subdural hematoma. Why does warfarin increase the risk of hemorrhage in this case?

💡 Explanation

Warfarin inhibits vitamin K epoxide reductase, which is required for the synthesis of functional clotting factors II, VII, IX, and X in the liver. Because warfarin reduces the concentration of these factors, the blood's ability to clot decreases; therefore, even a minor fall can lead to significant bleeding, rather than hemostasis.

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