Dosing guidelines, not protocols, for managing warfarin therapy

Beginning in 2009, the Joint Commission implemented National Patient Safety Goal (NPSG) 3E (now called NPSG 03.05.01) to “reduce the likelihood of harm associated with the use of anticoagulation therapy.”1 One of the elements of performance of this goal is that hospitals “use approved protocols for the initiation and maintenance of anticoagulant therapy.” In a recent article published in AJHP, Darryl Rich,2 a Joint Commission surveyor, attempted to clarify what constitutes a protocol in this context. As experienced clinicians in the field of antithrombotic pharmacotherapy who have faced the challenges of compliance with this NPSG in our own practices and discussed these issues with hundreds of clinicians across the country, we have concerns about some of Rich’s statements and feel that further clarification is needed. Most pharmacists practicing in health systems are familiar with heparin dosing protocols. These protocols are typically used by prescribers to order a weight-based loading dose of heparin (in units per kilogram of body weight) followed by dosage adjustments (in units per kilogram of body weight per hour or units per hour) that are based on the results of coagulation tests such as activated partial thromboplastin time or antifactor Xa levels. Dosage adjustments may be made by nursing staff, pharmacists, or physicians, depending on the type of program used within the institution. Recommended loading doses and target ranges may differ depending on the condition being treated. For example, higher doses may be required in patients with venous thromboembolism (VTE) compared with patients receiving heparin for acute coronary syndrome.