Reduction in anticoagulation-related adverse drug events using a trigger-based methodology

Jt Comm J Qual Patient Saf. 2005 Jun;31(6):313-8. doi: 10.1016/s1553-7250(05)31040-3.


Background: An initiative was undertaken by Novant Health System to address warfarin-related adverse drug events (ADEs) using lab-based patient-specific International Normalized Ratio (INR) triggers and pharmacy-based patient-specific Vitamin K triggers. The goal was to reduce ADEs related to the use of warfarin in both the inpatient and outpatient settings. Process improvements and medication management protocols were developed for patients managed with warfarin anticoagulation.

Methods: During each month's seven-day sampling period, the hospital information system generated the lab and pharmacy triggers, and the clinical pharmacists used these patient-specific triggers to identify the patient charts for review. All triggered charts were reviewed. Preliminary harm classification based on the National Coordinating Council for Medication Error Reporting and Prevention (NCC MERP) index was assigned by the clinical pharmacists and recorded for each patient.

Results: The system achieved reductions in ADEs related to warfarin administration on an inpatient management (45%) and outpatient management (52%) basis.

Discussion: Although based on inpatient facility-generated triggers, the initiative also served as a reasonable outpatient model, with improvements seen in the outpatient physician intervention groups.

MeSH terms

  • Adverse Drug Reaction Reporting Systems
  • Anticoagulants / adverse effects*
  • Clinical Protocols
  • Coagulants / therapeutic use
  • Drug Monitoring / methods*
  • Humans
  • Inpatients
  • International Normalized Ratio
  • Medical Records Systems, Computerized
  • Nursing Staff
  • Outpatients
  • Vitamin K / therapeutic use
  • Warfarin / adverse effects*


  • Anticoagulants
  • Coagulants
  • Vitamin K
  • Warfarin