Evaluating Warfarin Management by Pharmacists in a Community Teaching Hospital

OBJECTIVE: The purpose of this study was to evaluate warfarin management by pharmacists compared with physicians through an inpatient anticoagulation management service (AMS). DESIGN: Retrospective cohort study. SETTING: Community teaching hospital. PATIENTS, PARTICIPANTS: Patients were randomly selected from the Inpatient AMS from January 1, 2009 to January 1, 2011. Patients were included if they were 18 of age years or older and received warfarin for at least three days and excluded for indefinite warfarin discontinuation or an indication following orthopedic surgery. A total of 179 patients were included in each group. INTERVENTIONS: The electronic medical record was reviewed for demographics, warfarin indication and goal range, international normalized ratios (INRs), albumin, drug-drug interactions, bleeding, and thrombotic rates. MAIN OUTCOME MEASURES: Primary endpoints included mean time to therapeutic INR, mean time within goal, frequency of supratherapeutic INRs, bleeding, thrombotic rates, and mean INR on discharge. RESULTS: There was no statistically significant difference in the time required to reach a therapeutic INR; 3.17 vs. 2.65 days (95% confidence interval -0.09-1.13; P = 0.093). However, the pharmacist group resulted in a lower frequency of supratherapeutic INRs and significantly more time within goal range. CONCLUSION: Similar results were observed for pharmacist-managed and physician-managed patients for INR monitoring and outcome rates. However, the pharmacist-managed patients demonstrated a lower incidence of supratherapeutic INRs and significantly more time within goal.