Clinical experience with oral versus intravenous vitamin K for warfarin reversal.
Summary of "Clinical experience with oral versus intravenous vitamin K for warfarin reversal."
BACKGROUND:
Reversal of warfarin with plasma accounts for a large amount of fresh-frozen plasma transfused in the United States. The use of vitamin K is an alternate strategy. STUDY DESIGN AND
METHODS:
Records of vitamin K prescriptions for warfarin reversal were examined and recipients identified where data were available on dosage, route of administration (oral [PO] and intravenous [IV]) and the availability of both pre- and postadministration international normalized ratio(s) (INRs).
RESULTS:
A total of 135 administration events were evaluated: 81 PO and 54 IV. The median (range) preadministration INRs were 5.8 (1.9-16.5) versus 5.0 (1.4-16.5; p = 0.61) and the median (range) for the postadministration INRs were 2.4 (1.0-10.4) and 2.1 (1.2-8.2; p < 0.01) for the PO and IV routes, respectively. The median (range) doses were 2.5 (1-10) and 2.0 (1-10) mg for PO and IV, respectively (p < 0.01). A total of 44% of the IV vitamin K group achieved an INR of 2 or less within 12 hours versus 14% for the PO route (p < 0.01). In multilinear regression the preadministration INR (r = 0.14, p < 0.01) and time after administration (r = -0.05, p < 0.01) were independent variables influencing the postadministration INR but the dose administered (r = 0.09, p = 0.07) was not.
CONCLUSION:
Vitamin K needs to be given IV if urgent partial correction (<12 hr) of warfarin is required. No influence of dose administered in the range 1 to 10 mg on the postadministration INR was observed.
Affiliation
From the Blood Bank and Department of Medicine, Roger Williams Hospital, Providence, Rhode Island.
Journal Details
This article was published in the following journal.
Name: Transfusion
ISSN: 1537-2995
Pages:
Links
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/22738309
- DOI: http://dx.doi.org/10.1111/j.1537-2995.2012.03755.x
Medical and Biotech [MESH] Definitions
Warfarin
An anticoagulant that acts by inhibiting the synthesis of vitamin K-dependent coagulation factors. Warfarin is indicated for the prophylaxis and/or treatment of venous thrombosis and its extension, pulmonary embolism, and atrial fibrillation with embolization. It is also used as an adjunct in the prophylaxis of systemic embolism after myocardial infarction. Warfarin is also used as a rodenticide.
Vitamin K
A lipid cofactor that is required for normal blood clotting. Several forms of vitamin K have been identified: VITAMIN K 1 (phytomenadione) derived from plants, VITAMIN K 2 (menaquinone) from bacteria, and synthetic naphthoquinone provitamins, VITAMIN K 3 (menadione). Vitamin K 3 provitamins, after being alkylated in vivo, exhibit the antifibrinolytic activity of vitamin K. Green leafy vegetables, liver, cheese, butter, and egg yolk are good sources of vitamin K.
Oral Medicine
A branch of dentistry dealing with diseases of the oral and paraoral structures and the oral management of systemic diseases. (Hall, What is Oral Medicine, Anyway? Clinical Update: National Naval Dental Center, March 1991, p7-8)
Evidence-based Dentistry
An approach or process of practicing oral health care that requires the judicious integration of systematic assessments of clinical relevant scientific evidence, relating to the patient's oral and medical condition and history, with the dentist's clinical expertise and the patient's treatment needs and preferences. (from J Am Dent Assoc 134: 689, 2003)
Vitamin D Deficiency
A nutritional condition produced by a deficiency of VITAMIN D in the diet, insufficient production of vitamin D in the skin, inadequate absorption of vitamin D from the diet, or abnormal conversion of vitamin D to its bioactive metabolites. It is manifested clinically as RICKETS in children and OSTEOMALACIA in adults. (From Cecil Textbook of Medicine, 19th ed, p1406)
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