Title: Evaluation of an Institutional Inpatient Warfarin Policy Within an Academic Health System
Authors: Conner Correll Cain; Hannah Young; Gabrielle Iliff; Laura Holden
Background: Warfarin is a commonly used anticoagulant with a narrow therapeutic window that requires precise management to avoid complications. Pharmacist involvement has been shown to optimize warfarin therapy and improve patient outcomes; however, many institutions lack dedicated anticoagulation stewardship roles. This study aimed to evaluate compliance with an institutional anticoagulation monitoring policy for inpatient warfarin management to identify opportunities for a pharmacist-driven anticoagulation stewardship program.
Methods: This multicenter, retrospective cohort study evaluated adult patients administered warfarin at a Prisma Health inpatient facility between February 1, 2024 and August 1, 2024. The primary outcome was overall compliance with the institutional anticoagulation monitoring policy, defined as a composite of baseline international normalized ratio (INR) prior to the first scheduled warfarin dose, daily INR levels ordered until two consecutive therapeutic INRs were achieved on a stable dose, and weekly INR monitoring thereafter. Secondary outcomes included compliance with individual policy components, frequency of pharmacy consultation for warfarin management, time to therapeutic INR, incidence of supratherapeutic INR, warfarin reversal, appropriate bridge therapy, direct oral anticoagulant (DOAC) candidacy, prior to admission medication history, and discharge education.
Results: Of the 500 patient encounters reviewed, 418 met inclusion criteria. The vast majority (93.3%) were compliant with INR monitoring per institutional policy. Pharmacy consultation for warfarin management occurred in 49.8% of the encounters. Appropriate bridge therapy was significantly more common when pharmacy was consulted compared to no consultation (91.3% and 75.4%, p=0.01). Pharmacy completion of prior to admission medication histories occurred in fewer than half of the encounters, whereas warfarin discharge education was completed in over half of the encounters (48.9% and 62.9%).
Conclusions: There was widespread compliance with Prisma Health’s inpatient anticoagulation monitoring policy. Secondary outcomes suggest opportunities to improve pharmacy involvement during transitions of care.
Resident Contact:
[email protected]
