Difficulty: Medium
Average Score: 65%
Practice
The nurse is caring for a client who is receiving heparin therapy. Which laboratory value should the nurse monitor to determine the effectiveness of the therapy?
Correct answer
C
Rationale
The correct answer is C: International normalized ratio (INR). INR is used to monitor the effectiveness of heparin therapy because it provides a standardized measurement of the blood's ability to clot. A higher INR indicates a longer clotting time, showing that heparin is working effectively.
A: Prothrombin time (PT) measures the extrinsic pathway of the clotting cascade and is used to monitor warfarin therapy, not heparin.
B: Partial thromboplastin time (PTT) measures the intrinsic pathway and is used to monitor heparin therapy, but INR is more specific for heparin monitoring.
D: Activated partial thromboplastin time (aPTT) is similar to PTT and is used to monitor heparin therapy, but INR is a more reliable indicator of heparin's effectiveness.
A: Prothrombin time (PT) measures the extrinsic pathway of the clotting cascade and is used to monitor warfarin therapy, not heparin.
B: Partial thromboplastin time (PTT) measures the intrinsic pathway and is used to monitor heparin therapy, but INR is more specific for heparin monitoring.
D: Activated partial thromboplastin time (aPTT) is similar to PTT and is used to monitor heparin therapy, but INR is a more reliable indicator of heparin's effectiveness.