The Nurse Is Preparing to Provide Coumadin 5 Mg Po

The nurse is preparing to provide Coumadin 5 mg po to a female patient with an artificial heart valve.Which of the following lab values would cause the nurse to withhold the medication?

A) Activated partial thromboplastin time (aPTT) = 25 seconds
B) Fibrinogen = 250 mg/dL
C) International normalized ratio (INR) = 2.7
D) Prothrombin time (PT) = 22 seconds