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Failure mode and effects analysis to reduce risk of anticoagulation levels above the target range during concurrent
Lisa M Daniels1, Jason N Barreto1, John C Kuth1
1Lisa M. Daniels, M.D., is Resident Physician, Department of Internal Medicine; Jason N. Barreto, Pharm.D., is Assistant Professor of Pharmacy and Pharmacist, Pharmacy Services; John C. Kuth, Pharm.D., is Regional Director of Patient Safety and Pharmacist, Quality Resources; Jeremy R. Anderson, Pharm.D., is Pharmacist, Pharmacy Services; Beilei Zhang, Ph.D., is Systems Analyst, Division of Systems and Procedures; Andrew J. Majka, M.D., is Assistant Professor of Medicine and Physician, Division of General Internal Medicine; Timothy I. Morgenthaler, M.D., is Professor of Medicine and Physician, Division of Pulmonary and CriticalCare Medicine; and Pritish K. Tosh, M.D., is Assistant Professor of Medicine and Physician, Division of Infectious Diseases, Mayo Clinic Rochester, Rochester, MN.
Purpose:
A failure mode and effects analysis (FMEA) was conducted to analyze the clinical and operational processes leading to above-target International Normalized Ratios (INRs) in warfarin-treated patients receiving concurrent antimicrobial therapy.
Methods:
The INRs of patients on long-term warfarin therapy who received a course of trimethoprim-sulfamethoxazole, metronidazole, fluconazole, miconazole, or voriconazole (highly potentiating antimicrobials, or HPAs) between September 1 and December 31, 2011, were compared with patients on long-term warfarin therapy who did not receive any antimicrobial during the same period. A multidisciplinary team of physicians, pharmacists, and a systems analyst was then formed to complete a step-by-step outline of the processes involved in warfarin management and concomitant HPA therapy, followed by an FMEA.
Results:
Patients taking trimethoprim-sulfamethoxazole, metronidazole, or fluconazole demonstrated a significantly increased risk of having an INR of >4.5. The FMEA identified 134 failure modes. The most common failure modes were as follows: (1) electronic medical records did not identify all patients receiving warfarin, (2) HPA prescribers were unaware of recommended warfarin therapy when HPAs were prescribed, (3) HPA prescribers were unaware that a patient was taking warfarin and that the drug interaction is significant, and (4) warfarin managers were unaware that an HPA had been prescribed for a patient.
Conclusion:
An FMEA determined that the risk of adverse events caused by concomitantly administering warfarin and HPAs can be decreased by preemptively identifying patients receiving warfarin, having a care process in place, alerting providers about the patient's risk status, and notifying providers at the anticoagulation clinic.
Insights
A failure mode and effects analysis (FMEA) identified key risks in managing warfarin and highly potentiating antimicrobial (HPA) drug interactions. Improving patient identification and provider communication can reduce adverse events.
Area of Science:
- Pharmacology
- Clinical Pharmacy
- Patient Safety
Background:
- Warfarin therapy requires careful management due to its narrow therapeutic index.
- Concurrent administration of certain antimicrobials can significantly potentiate warfarin's effect, increasing bleeding risk.
- Identifying and mitigating risks associated with drug-drug interactions is crucial for patient safety.
Purpose of the Study:
- To conduct a failure mode and effects analysis (FMEA) on clinical and operational processes leading to elevated International Normalized Ratios (INRs) in warfarin patients receiving concurrent antimicrobial therapy.
- To identify specific failure modes in the management of warfarin and highly potentiating antimicrobial (HPA) drug interactions.
Main Methods:
- A comparative analysis of INRs in warfarin patients receiving specific HPAs versus those not receiving antimicrobials.
- A multidisciplinary team performed a step-by-step process outline of warfarin management and HPA therapy.
- A failure mode and effects analysis (FMEA) was conducted on the identified processes.
Main Results:
- Patients on trimethoprim-sulfamethoxazole, metronidazole, or fluconazole had a significantly increased risk of INR >4.5.
- The FMEA identified 134 failure modes, including EMRs failing to identify all warfarin patients.
- Common failures involved prescribers' lack of awareness regarding warfarin therapy, drug interactions, and concomitant HPA prescriptions.
Conclusions:
- Implementing preemptive patient identification for warfarin users is essential.
- Establishing a robust care process with provider alerts for risk status is recommended.
- Notifying anticoagulation clinic providers about concurrent HPA use can decrease adverse event risk.
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