Coagulation Factors

General

Synonym/Acronym:
See table on the next page.

Rationale
To detect factor deficiencies and related coagulopathies such as found in disseminated intravascular coagulation (DIC).

Patient Preparation
There are no food, fluid, activity, or medication restrictions unless by medical direction.

Normal Findings
(Method: Photo-optical clot detection) Activity from 50% to 150%.

Preferred NameSynonymRole in Modern Coagulation Cascade ModelCoagulation Test Responses in the Presence of Factor Deficiency
Factor IFibrinogenAssists in the formation of the fibrin clotPT prolonged, aPTT prolonged
Factor IIProthrombinPrethrombinAssists 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 hemostasisPT prolonged, aPTT prolonged
Tissue factor (TF) (formerly known as factor III)TFTissue thromboplastinAssists factor VII and Ca2+ in the activation of factors IX and X during the initiation phase of hemostasisPT prolonged, aPTT prolonged
Calcium (formerly known as factor IV)CalciumCa2+Essential to the activation of multiple clotting factorsN/A
Factor VProaccelerinLabile factor, accelerator globulin (AcG)Assists factors VIIIa, IXa, Xa, and II in the formation of thrombin during the amplification and propagation phases of hemostasisPT prolonged, aPTT prolonged
Factor VIIProconvertinStabile factor, serum prothrombin conversion accelerator, autoprothrombin IAssists TF and Ca2+ in the activation of factors IX and XPT prolonged, aPTT normal
Factor VIIIAntihemophilic factor (AHF)Antihemophilic globulin (AHG), antihemophilic factor A, platelet cofactor 1Activated by trace thrombin during the initiation phase of hemostasis to amplify formation of additional thrombinPT normal, aPTT prolonged
Factor IXPlasma thromboplastin component (PTC)Christmas factor, antihemophilic factor B, platelet cofactor 2Assists factors Va and VIIIa in the amplification phase and factors VIIIa, Xa, Va, and II to form thrombin in the propagation phasePT normal, aPTT prolonged
Factor XStuart-Prower factorAutoprothrombin III, thrombokinaseAssists with formation of trace thrombin in the initiation phase and acts with factors VIIIa, IXa, Va, and II to form thrombin in the propagation phasePT prolonged, aPTT prolonged
Factor XIPlasma thromboplastin antecedent (PTA)Antihemophilic factor CActivated 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 fibrinolysisPT normal, aPTT prolonged
Factor XIIHageman factorGlass factor, contact factorContact activator of the kinin system (e.g., prekallikrein, and high-molecular-weight kininogen)PT normal, aPTT prolonged
Factor XIIIFibrin-stabilizing factor (FSF)Laki-Lorand factor (LLF), fibrinase, plasma transglutaminaseActivated by thrombin and assists in formation of bonds between fibrin strands to complete secondary hemostasisPT normal, aPTT normal
von Willebrand factorvon Willebrand factorvWFAssists in platelet adhesion and thrombus formationRistocetin cofactor decreased

Critical Findings and Potential Interventions

  • Fibrinogen: Less than 80 mg/dL (SI: Less than 2.4 micromol/L)

Timely notification to the requesting health-care provider (HCP) of any critical findings and related symptoms is a role expectation of the professional nurse. A listing of these findings varies among facilities.

Signs and symptoms of microvascular thrombosis include cyanosis, ischemic tissue necrosis, hemorrhagic necrosis, tachypnea, dyspnea, pulmonary emboli, venous distention, abdominal pain, and oliguria. Possible interventions include identification and treatment of the underlying cause, support through administration of required blood products (cryoprecipitate or fresh frozen plasma), and administration of heparin. Cryoprecipitate may be a more effective product than fresh frozen plasma in cases where the fibrinogen level is less than 100 mg/dL (SI: 2.94 micromol/L), the minimum level required for adequate hemostasis, because it delivers a concentrated amount of fibrinogen without as much plasma volume. Further information regarding fibrinogen can be found in the study titled “Fibrinogen.

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