Question

A nurse is caring for a client who has a new prescription for warfarin. The nurse should use the results of which of the following diagnostic tests to monitor the effect of this therapy?

A. Prothrombin time (PT) Rationale: The PT, reported as an INR, is used to monitor warfarin therapy.
B. Platelet count Rationale: The platelet count is used to monitor for adverse effects of cancer chemotherapy. Warfarin does not affect the platelet count.
C. White blood cell count (WBC) Rationale: The WBC is used to monitor antibiotic therapy for a client who has a bacterial infection.
D. Activated partial thromboplastin time (aPTT) Rationale: The aPTT is used to monitor heparin therapy.

Answer 1

To monitor warfarin therapy, nurses should use the Prothrombin Time test, reported as an INR, which assesses how long it takes for blood to clot and determines the effectiveness of the anticoagulant therapy.

Step-by-step explanation:

Monitoring Warfarin Therapy

When a patient has a new prescription for warfarin, a nurse should monitor the effect of this therapy using the Prothrombin Time (PT) test. The PT is reported as an International Normalized Ratio (INR), which is a standardized number that ensures the results are consistent regardless of the test methods used. An increased INR indicates a longer time for blood to clot, which means warfarin is effectively thinning the patient's blood to prevent excessive clotting. It is important to note that PT/INR is specifically used to monitor warfarin therapy, while other tests such as the Activated Partial Thromboplastin Time (aPTT) are used to monitor different anticoagulants like heparin.

Platelet count and White Blood Cell (WBC) count are not appropriate tests for monitoring warfarin therapy. Platelet count is more relevant in monitoring for adverse effects of cancer chemotherapy, and WBC count is indicative of infection and used to monitor the effectiveness of antibiotic therapy. The correct use of coagulation tests is instrumental in managing warfarin therapy and ensuring patient safety.