Date of Award

Spring 5-23-2015

Document Type

Doctor of Nursing Practice Final Manuscript

Degree Name

Doctor of Nursing Practice



First Advisor

Karen Macauley PhD DNP FNP-BC GNP-BC

Second Advisor

Kathy James DNSc, FNP-BC, FAAN


Background: Warfarin is the oral anticoagulant that is most commonly used to control and prevent thromboembolic disorders. It requires meticulous testing and dosing adjustments to attain therapeutic international normalized ratio (INR) levels. Patient self-testing (PST) is associated with a reduced risk of all-cause mortality and lower rates of thromboembolism and bleeding. PST meters offers convenience and promotes self-initiative of care.

Purpose: The purpose of the project is to evaluate the effectiveness of INR PST in adult patients diagnosed with atrial fibrillation, deep vein thrombosis, and mechanical heart valve on warfarin therapy in a Cardiology practice compared to traditional laboratory methods, or usual care.

Description of Design: Chart reviews were conducted to identify patients on warfarin (for greater than six months) with the medical indication of atrial fibrillation, deep vein thrombosis, and mechanical heart valve. Data obtained from medical records included INR lab values, age, gender, medical indication, method of testing, and insurance carrier. INR lab values were analyzed over a four-year time period (August 2010 – August 2014) for control of INRs based on method of testing.

Outcomes: Pre- and post- data reveal patients had tighter INR control after PST initiation. A statistically significant trend is noted at the three-month point from date of initiation, where the group experienced less therapeutic control, however control of INRs continued to be tighter compared to usual care.

Statement of Conclusions: The data suggests adult patients on warfarin utilizing PST method of INR testing showed tighter control of INRs as compared to usual care.

Implications for practice: Based on the data obtained, the six months following the three month PST initiation suggested provider follow-up after three months of initiation to re-evaluate testing frequency and goals.