ITC ProTime Microcoagulation System - Manual (Page 2)

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INTENDED USE
The ProTime Microcoagulation System is a portable, battery-operated instrument with a disposable cuvette
for quantitative determination of prothrombin time from fingerstick whole blood or anticoagulant-free
venous whole blood. The product is intended for use in the management of patients treated with oral
anticoagulants by a healthcare professional and for patient self-testing. Additional information for medical
professionals to monitor patients is located at the end of this instruction manual. Materials are available
through ITC for professionals to train patient self-testers using the ProTime Microcoagulation System.
ProTime instruments intended for patient self-testing are available in the U.S. by prescription only. These
instruments include patient-specific product instructions.
For in vitro Diagnostic Use.
SUMMARY AND EXPLANATION
What Does The ProTime Microcoagulation System Do?
The ProTime Microcoagulation System is designed for testing prothrombin time (PT) and International
Normalized Ratio (INR). The reagents for a prothrombin time test are in the cuvette. Whole blood clotting
time is converted to INR, than the result is calculated for plasma equivalent PT seconds. This test is done to
check the status of patients receiving oral anticoagulation therapy.
What is INR?
The International Normalized Ratio (INR) was developed to help the doctor compare an individual’s
prothrombin time results from one lab to another. An advantage of reporting an INR is to allow for
normalization of comparisons from one lab or instrument to another. The precision of the INR is improved
when a reagent with a lower ISI is used.
Note: ISI stands for International Sensitivity Index. ProTime uses this number to calculate PT
seconds from INR.
Blood Coagulation Test Methodology
Traditional coagulation tests measure the time required for the formation of a fibrin clot following the
addition of a coagulation-activating reagent. Laboratory assays typically use plasma recovered from
anticoagulated (citrated) whole blood samples. The clotting time is a measure of the functionality of the
patient’s hemostatic system. Specific coagulation activating reagents are employed in various clotting tests to
measure specific components of the hemostasis system. Clotting times are prolonged in the case of either
decreased procoagulant activity or increased anticoagulant activity.
Summary of the Blood Coagulation System
The events leading to the formation of a fibrin clot are simplified in coagulation theory into two coagulation
pathways: the intrinsic and the extrinsic pathways. There are twelve clotting factors or proteins involved in
this cascade scheme, numbered I through XIII (excluding VI). The prothrombin time test measures the
extrinsic coagulation pathway and is sensitive to coagulation Factors VII, X, V, II and Fibrinogen (I). With the
exception of Factor V, vitamin K is a required co-factor for biosynthesis of these factors in the liver. The
prothrombin time (PT) test uses thromboplastin as the active reagent to initiate the extrinsic pathway. The
prothrombin time test will be prolonged in patients with liver disease or vitamin K deficiency. The test is
widely used to monitor oral anticoagulant therapy that suppresses the synthesis of vitamin K-dependent
clotting factors.