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To detect factor deficiencies and related coagulopathies such as found in disseminated intravascular coagulation (DIC).
Whole blood collected in a completely filled blue-top (3.2% sodium citrate) tube. If the patient’s hematocrit exceeds 55%, the volume of citrate in the collection tube must be adjusted.
(Method: Photo-optical clot detection) Activity from 50% to 150%.
|Preferred Name||Synonym||Role in Modern Coagulation Cascade Model||Coagulation Test Responses in the Presence of Factor Deficiency|
|Factor I||Fibrinogen||—||Assists in the formation of the fibrin clot||PT prolonged, aPTT prolonged|
|Factor II||Prothrombin||Prethrombin||Assists factor Xa in formation of trace thrombin in the initiation phase and assists factors VIIIa, IXa, Xa, and Va to form thrombin in the propagation phase of hemostasis||PT prolonged, aPTT prolonged|
|Tissue factor (formerly known as factor III)||Tissue factor||Tissue thromboplastin||Assists factor VII and Ca2+ in the activation of factors IX and X during the initiation phase of hemostasis||PT prolonged, aPTT prolonged|
|Calcium (formerly known as factor intravenous)||Calcium||Ca2+||Essential to the activation of multiple clotting factors||N/A|
|Factor V||Proaccelerin||Labile factor, accelerator globulin (AcG)||Assists factors VIIIa, IXa, Xa, and II in the formation of thrombin during the amplification and propagation phases of hemostasis||PT prolonged, aPTT prolonged|
|Factor VII||Proconvertin||Stabile factor, serum prothrombin conversion accelerator, autoprothrombin I||Assists tissue factor and Ca2+ in the activation of factors IX and X||PT prolonged, aPTT normal|
|Factor VIII||Antihemophilic factor (AHF)||Antihemophilic globulin (AHG), antihemophilic factor A, platelet cofactor 1||Activated by trace thrombin during the initiation phase of hemostasis to amplify formation of additional thrombin||PT normal, aPTT prolonged|
|Factor IX||Plasma thromboplastin component (PTC)||Christmas factor, antihemophilic factor B, platelet cofactor 2||Assists factors Va and VIIIa in the amplification phase and factors VIIIa, Xa, Va, and II to form thrombin in the propagation phase||PT normal, aPTT prolonged|
|Factor X||Stuart-Prower factor||Autoprothrombin III, thrombokinase||Assists with formation of trace thrombin in the initiation phase and acts with factors VIIIa, IXa, Va, and II to form thrombin in the propagation phase||PT prolonged, aPTT prolonged|
|Factor XI||Plasma thromboplastin antecedent (PTA)||Antihemophilic factor C||Activated by thrombin produced in the extrinsic pathway to enhance production of additional thrombin inside the fibrin clot via the intrinsic pathway; this factor also participates in slowing down the process of fibrinolysis||PT normal, aPTT prolonged|
|Factor XII||Hageman factor||Glass factor, contact factor||Contact activator of the kinin system (e.g., prekallikrein, and high-molecular-weight kininogen)||PT normal, aPTT prolonged|
|Factor XIII||Fibrin-stabilizing factor (FSF)||Laki-Lorand factor (LLF), fibrinase, plasma transglutaminase||Activated by thrombin and assists in formation of bonds between fibrin strands to complete secondary hemostasis||PT normal, aPTT normal|
|von Willebrand factor||von Willebrand factor||vWF||Assists in platelet adhesion and thrombus formation||Ristocetin cofactor decreased|