Abstract
Rapid reduction of excessively high international normalized ratio (INR) values into the therapeutic range is necessary in patients who must be maintained on oral anticoagulants but who present with an overdose. We prospectively studied the effect of observation alone versus escalating low doses of intravenous vitamin K on 23 patients presenting with no overt evidence of hemorrhage and INR values in excess of 10. Two of six patients observed without intervention developed spontaneous hemorrhage. Only one of the observed patients and none of 4 patients given 100-200 µg-vitamin K had INR values less than 5.0 by 24 hours. Three of the four patients receiving 500 µg of vitamin K had INR values less than 5.0, with two of these being less than 3.5 within the first 24 hours. Nine patients receiving 1000 µg of vitamin K had INR values between 1.7 and 3.5 by 24 hours. In none of these nine patients did the INR subsequently normalize, and there were no difficulties re-establishing anticoagulant therapy. No adverse effects were noted in any of the patients receiving intravenous vitamin K. We recommend 1000 µg of intravenous vitamin K as a safe and effective means of rapidly reversing excessively anticoagulated patients presenting with INR values greater than 10 units.
Similar content being viewed by others
References
Levine MN, Hirsh J, Landefeld S, Roskob G. Hemorrhagic complications of anticoagulant treatment. Chest 1992;102(Suppl):3525–3635.
Landefeld CS, Beyth RJ. Anticoagulant-related bleeding: clinical epidemiology, prediction, and prevention. Am J Med 1993;95:315.
Hirsh J, Dalen JE, Deykin D, Poller L. Oral anticoagulants: Mechanism of action, clinical effectiveness, and optimal therapeutic range. Chest 1992;102:312S–326S.
Stults BM, Dere WH, Caine TH. Long-term anticoagulation: Indications and management. West J Med 1989;151:414–429.
Andersen P, Godal HC. Predictable reduction in anticoagulant activity of warfarin by small amounts of vitamin K. Acta Med Scand 1975;198:269–270.
Taberner DA, Thomson JM, Poller L. Comparison of prothrombin complex concentrate and vitamin K1 in oral anticoagulant reversal. Br Med J 1976;2:83–85.
Shetty HGM, Backhouse G, Bentley DP, Routledge PH. Effective reversal of warfarin-induced excessive anticoagulation with low dose vitamin K. Thomb Haemost 1992;67:13–15.
Hull R, Hirsh J, Jay R, et al. Different intensitics of oral anticoagulant therapy in the treatment of proximal-vein thrombosis. N Engl J Med 1982;307:1676–1681.
Turpie AGG, Gunstensen J, Hirsh J, et al. Randomized comparison of two intensities of oral anticoagulant therapy after tissue heart valve replacement. Lancet 1988;1:1242–1245.
Saour JW, Sieck JO, Mamo LAR, et al. Trial of different intensities of anticoagulation in patients with prosthetic heart valves. N Engl J Med 1990;322:428–432.
Altman P, Rouvier J, Gurfinkel E, et al. Comparison of two levels of anticoagulant therapy in patients with substitute heart valves. J Thorac Cardiovas Surg 1991;101:427–431.
Pengo V, Banzato A, Garelli E, Zass A, Biasiolo A. Reversal of excessive effect of regular anticoagulation: Low dose of phytonadione (Vitamin K1) compared with warfarin discontinuation. Blood Coagul Fibrinolys 1993;4:739–741.
Martin JC. Anaphylactoid reactions and vitamin K. Med J Aust 1991;155:851.
Rich EC, Drage CW. Severe complications of intravenous phytondione therapy. Postgrad Med 1982;72:303–306.
Rubia J, Grau E, Montserrat I, Zuazu I, Paya A. Anaphylactic shock and vitamin K1. Ann Intern Med 1989;110:943.
Lefrere JJ, Girot R. Acute cardiovascular collapse during intravenous vitamin K1 injection. Thromb Haemost 1987;58–790
Labatut A, Sorbrette F, Virenque CH. Etats de choc lors d'injection de vitamine K. Therapie 1988;43:58.
Barash P, Kitahata LM, Mandel S. Acute cardiovascular collapse after intravenous phytonadione. Anesth Anuly 1976;55:304–306.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Brophy, M.T., Fiore, L.D. & Deykin, D. Low-Dose Vitamin K Therapy in Excessively Anticoagulated Patients: A Dose-Finding Study. J Thromb Thrombolysis 4, 289–292 (1997). https://doi.org/10.1023/A:1008811421946
Issue Date:
DOI: https://doi.org/10.1023/A:1008811421946