Progressive Care Nursing Certification (PCCN) Practice Exam

What is the therapeutic range for anticoagulation in a patient with atrial fibrillation on warfarin?

1. INR less than 1.0

2. INR between 1.0 and 1.5

3. INR between 2.5 and 3.5

4. INR between 4.5 and 6.0

The correct answer is: INR between 2.5 and 3.5

The therapeutic range for anticoagulation in a patient with atrial fibrillation who is on warfarin is typically between 2.0 and 3.0, although some guidelines may specify a target of 2.5 to 3.5, particularly for certain patient populations or conditions. This range is crucial as it reduces the risk of thromboembolic events such as stroke while also minimizing the potential for bleeding complications that can occur with excessive anticoagulation. Aiming for this INR range helps to ensure that the blood's clotting ability is sufficiently impaired to prevent clots that can lead to strokes, which is a common concern in atrial fibrillation patients, while also avoiding the increased risks associated with bleeding. Maintaining the INR within the therapeutic range requires regular monitoring and dose adjustments of warfarin, as various factors can influence INR levels. The other options fall outside this therapeutic range, thus leading to either insufficient or excessive anticoagulation. An INR less than 1.0 indicates a risk of clot formation, while an INR between 1.0 and 1.5 is inadequate for anticoagulation purposes. An INR between 4.5 and 6.0 suggests a significant risk for major bleeding, which is