Reduction in Warfarin Adverse Events Requiring Patient Hospitalization After Implementation of a Pharmacist‐Managed Anticoagulation Service

STUDY OBJECTIVE: To compare adverse events related to anticoagulation in patients assigned to a pharmacist-managed anticoagulation service versus those receiving usual care. DESIGN: Retrospective cohort analysis. SETTING: Three hundred-bed community hospital. PATIENTS: Four hundred twenty patients referred for anticoagulation management. MEASUREMENTS AND MAIN RESULTS: Primary outcomes were the number of adverse events requiring patient hospitalization and the number of patients experiencing such events. Secondary outcomes were the median length of hospital stay/admission and the total number of hospital days. The total numbers of adverse events requiring hospitalization were three for the pharmacist-managed group and 14 for the usual care group (p=0.0153). The number of patients experiencing an adverse event requiring hospitalization was also lower for the pharmacist-managed group than for the usual care group (3 vs 10, p = 0.0962). The median length of hospital stay associated with each adverse event was not significantly different between the two groups; however, the total number of hospital days accrued was higher in the usual care group. CONCLUSION: At 6 months after discontinuation of the pharmacist-managed anticoagulation service, the frequency of adverse events increased significantly, resulting in both an increased number of hospitalizations and an increased number of hospital days accrued. This coordinated anticoagulation program using a pharmacist reduced warfarin-related complications.