와파린 복용 중 과도한 INR 상승 시 비출혈 환자에서 비타민 K1 사용의 후향적 평가

• Published in: 병원약사회지, 33(4) pp. 333 - 340
• Main Authors: 서비취, 문정연, 조은정, 조윤숙, 한현주
• Format: Journal Article
• Language: Korean
• Published: 한국병원약사회 01.11.2016
• Subjects: 약학
• ISSN: 1226-640X; 2466-2143
• DOI: 10.32429/jkshp.2016.33.4.001

Backgrounds : Warfarin, an oral anticoagulant, has narrow therapeutic range. Bleeding risk can rise dramatically in patients with supratherapeutic international normalized ratio (INR). There are various guidelines for correcting excessive anticoagulation. One of these is the 9th ACCP guideline. It suggests simply holding warfarin in non-bleeding patients with INR value of 4.5 to 10.0. Therefore, we evaluated the treatment methods for INR control at Seoul National University Hospital (SNUH). Methods : Patients with INR value of 4.5 to 10.0 without evidence of bleeding who were followed at an anticoagulation clinic in SNUH from September 2012 to August 2014 were included in this study. They were observed retrospectively based on medical records and anticoagulation clinic sheets. Patients were divided into two groups: 1) short-term warfarin withdrawal group, and 2) vitamin K1 group. We evaluated the incidence of INR over-correction, bleeding, and thromboembolic events in each group. Results : Most patients with 4.5 ≤ INR 6.0 were treated by temporarily holding warfarin. Finally, a total of 30 cases with INR value of 6.0 to 10.0 were analyzed, including 13 cases treated by temporarily holding warfarin and 17 cases treated by vitamin K1. INR over-correction was more frequent in the vitamin K1 group (11 cases (64.7%) in the vitamin K1 group vs. 1 case (7.7%) in the temporary warfarin withdrawal group, p=0.002). We found no significant difference in bleeding rate between the two treatment groups (minor bleeding in 1 case (7.7%) in the temporary warfarin withdrawal group and 1 case (5.9%) in the vitamin K1 group, p=0.687). There was no thromboembolic event or major bleeding in either group. Conclusion : Considering the risk of thromboembolism by INR over-correction, temporary warfarin withdrawal may be more appropriate than using vitamin K1 for non-bleeding patients with supratherapeutic INR without indications of acute reversal of excessive anticoagulation. KCI Citation Count: 0