Objective: Warfarin is used as the mainstay of oral anticoagulant therapy for the prevention and treatment of various thromboembolic disorders. Effective methods of managing anticoagulation are available, but underemployed. Standardized dosing protocols (nomograms) and anticoagulation management services are some ways to manage warfarin use. The primary objective of this study was to evaluate a difference in time in therapeutic range (TTR) of international normalized ratio (INR) level in physician-managed groups versus pharmacist-managed warfarin groups.
Methods:The institutional review board approved this single center, retrospective study which was conducted in a small community hospital. Men and women ages 44-97 who were previously on or began warfarin therapy during hospitalization were evaluated for selection. A total of 38 patients were randomly selected for the review during August-December 2017. The primary outcome of TTR in physician-versus pharmacist-managed warfarin groups was calculated. A two proportion Z-test was utilized for statistical analysis. Secondary outcomes included time with subtherapeutic INR, time with supratherapeutic INR, safety outcomes (bleeding, transfusion), and the need for bridge therapy.Results: Thirty-four total patients were included for the final review, and four were excluded as they switched from one group to another during the review period. The primary outcome, TTR, was higher in the pharmacist-managed group compared to the physician-managed group (p=0.03). Secondary outcomes were similar in both groups per descriptive statistics.
Conclusions:Pharmacist consults for warfarin management or auto consults for all orders should be considered more often. The clinical significance of TTR when warfarin is managed by pharmacists must be determined in larger, randomized clinical trials.