International Normalized Ratio (INR) | 合法醫療器材資訊網

由SShikdar著作·2020·被引用13次—PT/INRcanbeprolongedin:VKAs:Warfarininhibitsthegamma-carboxylationofthevitaminK-dependentfactors,includingfactorsII( ...

International normalized ratio (INR) is the preferred test of choice for patients taking vitamin K antagonists (VKA). It can also be used to assess the risk of bleeding or the coagulation status of the patients. Patients taking oral anticoagulants are required to monitor INR to adjust the VKA doses because these vary between patients. The INR is derived from prothrombin time (PT) which is calculated as a ratio of the patient’s PT to a control PT standardized for the potency of the thromboplastin reagent developed by the World Health Organization (WHO) using the following formula:

PT, the time in seconds, is measured in plasma to form a clot in the presence of sufficient concentration of calcium and tissue thromboplastin by activating coagulation via the extrinsic pathway. The refe...