Normal prothrombin time is within which range?

Normal prothrombin time is within which range?

• A. 8-12 seconds
• B. 6-9 seconds
• C. 12-15 seconds
• D. 20-25 seconds

Answer: (C)

Prothrombin time assesses how long the extrinsic pathway takes to form a clot. The normal reference range is roughly twelve to fifteen seconds (lab values may vary slightly). This range is used to monitor anticoagulation with warfarin and to evaluate vitamin K–dependent factor function. Times longer than this suggest a coagulopathy or anticoagulation effect, while shorter times are not typical. So the normal range is twelve to fifteen seconds.

Prothrombin time assesses how long the extrinsic pathway takes to form a clot. The normal reference range is roughly twelve to fifteen seconds (lab values may vary slightly). This range is used to monitor anticoagulation with warfarin and to evaluate vitamin K–dependent factor function. Times longer than this suggest a coagulopathy or anticoagulation effect, while shorter times are not typical. So the normal range is twelve to fifteen seconds.