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Prothrombin Time/International Normalized Ratio

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Haemostasis

Part of the book series: Methods in Molecular Biology ((MIMB,volume 992))

Abstract

Prothrombin time (PT) and/or International Normalized Ratio (INR) is the most commonly used coagulation assay in health care, to diagnose the risk of bleeding and to monitor oral anticoagulation therapy.

This test is based on the principle that in citrated plasma, the addition of a thromboplastin and CaCl2 allows for formation of a stable clot. The time required for the formation of a stable clot is recorded in seconds and represents the actual PT result. INR is calculated from the PT and allows for worldwide standardization of results.

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Author information

Authors and Affiliations

  1. Haematology Research Laboratory, Murdoch Childrens Research Institute, Melbourne, Australia

    Vera Ignjatovic

  2. Department of Paediatrics, The University of Melbourne, Melbourne, Australia

    Vera Ignjatovic

Authors
  1. Vera Ignjatovic
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Editor information

Editors and Affiliations

  1. Department of Paediatrics, University of Melbourne, n/a, Parkville, 3052, Victoria, Australia

    Paul Monagle

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© 2013 Humana Press

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Ignjatovic, V. (2013). Prothrombin Time/International Normalized Ratio. In: Monagle, P. (eds) Haemostasis. Methods in Molecular Biology, vol 992. Humana Press, Totowa, NJ. https://doi.org/10.1007/978-1-62703-339-8_9

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  • DOI: https://doi.org/10.1007/978-1-62703-339-8_9

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  • Publisher Name: Humana Press, Totowa, NJ

  • Print ISBN: 978-1-62703-338-1

  • Online ISBN: 978-1-62703-339-8

  • eBook Packages: Springer Protocols

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