Claire Tai1, Hilary Wu2, Cindy San3, Doson Chua4. 1. BSc(Pharm), ACPR, is a Clinical Pharmacist with Fraser Health, Surrey, British Columbia. 2. BSc(Pharm), ACPR, PharmD, is a Clinical Pharmacist with Providence Health Care, Vancouver, British Columbia. 3. BSc(Pharm), ACPR, PharmD, is a Clinical Pharmacy Specialist in Emergency Medicine with St Paul's Hospital, Providence Health Care, Vancouver, British Columbia. 4. BSc(Pharm), PharmD, BCPS (AQ), is a Clinical Pharmacy Specialist in Cardiology with St Paul's Hospital, Providence Health Care, and a Clinical Professor with the Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, British Columbia.
Abstract
BACKGROUND: For patients with supratherapeutic international normalized ratio (INR) and no evidence of bleeding, the 2012 guidelines of the American College of Chest Physicians discourage administration of vitamin K. At the study hospital, it was observed that vitamin K was frequently prescribed for patients with INR of 4.5 or higher and no bleeding. OBJECTIVES: To compare efficacy and safety outcomes between holding warfarin alone and holding warfarin with administration of vitamin K and to compare these outcomes among various doses and routes of vitamin K administration in non-critical care inpatients experiencing supratherapeutic INR without evidence of bleeding. METHODS: This single-centre retrospective chart review involved noncritical care inpatients with supratherapeutic INR (4.5-8.9) without evidence of bleeding. The primary outcomes were the change in INR 1 day after implementation of supratherapeutic INR management and the time to reach INR less than 3.0. The secondary outcomes were length of stay, frequency of warfarin resistance, incidence and duration of bridging anticoagulation, incidence of thromboembolism and major bleeding, and death. RESULTS: Regardless of vitamin K dose, the administration of vitamin K combined with holding warfarin, relative to holding warfarin alone, was associated with a greater INR decrease 1 day after the intervention (mean ± standard deviation -3.2 ± 1.9 versus -0.9 ± 1.0, p < 0.001) and a shorter time to reach INR below 3.0 (1.9 ± 1.0 days versus 2.6 ± 1.4 days, p = 0.003). No statistically significant differences in any other outcomes were observed. CONCLUSIONS: In hospitalized non-critical care patients with INR between 4.5 and 8.9 without evidence of bleeding, the combination of holding warfarin and administering vitamin K was associated with greater and faster decreases in INR than holding warfarin alone. No significant differences were found in clinically important outcomes. The practice of administering vitamin K in this population warrants further study and re-evaluation.
BACKGROUND: For patients with supratherapeutic international normalized ratio (INR) and no evidence of bleeding, the 2012 guidelines of the American College of Chest Physicians discourage administration of vitamin K. At the study hospital, it was observed that vitamin K was frequently prescribed for patients with INR of 4.5 or higher and no bleeding. OBJECTIVES: To compare efficacy and safety outcomes between holding warfarin alone and holding warfarin with administration of vitamin K and to compare these outcomes among various doses and routes of vitamin K administration in non-critical care inpatients experiencing supratherapeutic INR without evidence of bleeding. METHODS: This single-centre retrospective chart review involved noncritical care inpatients with supratherapeutic INR (4.5-8.9) without evidence of bleeding. The primary outcomes were the change in INR 1 day after implementation of supratherapeutic INR management and the time to reach INR less than 3.0. The secondary outcomes were length of stay, frequency of warfarin resistance, incidence and duration of bridging anticoagulation, incidence of thromboembolism and major bleeding, and death. RESULTS: Regardless of vitamin K dose, the administration of vitamin K combined with holding warfarin, relative to holding warfarin alone, was associated with a greater INR decrease 1 day after the intervention (mean ± standard deviation -3.2 ± 1.9 versus -0.9 ± 1.0, p < 0.001) and a shorter time to reach INR below 3.0 (1.9 ± 1.0 days versus 2.6 ± 1.4 days, p = 0.003). No statistically significant differences in any other outcomes were observed. CONCLUSIONS: In hospitalized non-critical care patients with INR between 4.5 and 8.9 without evidence of bleeding, the combination of holding warfarin and administering vitamin K was associated with greater and faster decreases in INR than holding warfarin alone. No significant differences were found in clinically important outcomes. The practice of administering vitamin K in this population warrants further study and re-evaluation.
Entities:
Keywords:
anticoagulation; anticoagulothérapie; international normalized ratio; phytonadione; rapport international normalisé; vitamin K; vitamine K; warfarin; warfarine
Authors: W Ageno; M Crowther; L Steidl; C Ultori; V Mera; F Dentali; A Squizzato; C Marchesi; A Venco Journal: Thromb Haemost Date: 2002-07 Impact factor: 5.249
Authors: G Palareti; N Leali; S Coccheri; M Poggi; C Manotti; A D'Angelo; V Pengo; N Erba; M Moia; N Ciavarella; G Devoto; M Berrettini; S Musolesi Journal: Lancet Date: 1996-08-17 Impact factor: 79.321
Authors: M A Crowther; J Julian; D McCarty; J Douketis; M Kovacs; L Biagoni; T Schnurr; J McGinnis; M Gent; J Hirsh; J Ginsberg Journal: Lancet Date: 2000-11-04 Impact factor: 79.321
Authors: Mark A Kotowycz; Kristian B Filion; Jacqueline Joza; Doris Dube; Matthew R Reynolds; Louise Pilote; Mark J Eisenberg; Vidal Essebag Journal: Can J Cardiol Date: 2011-05-04 Impact factor: 5.223