Normal Hemostasis

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        Normal Hemostasis
            Definition : Process by which bleeding at any site arrested by the formation of a hemostatic plug (clot plug).

    Components of Hemostasis
  • Blood vessels - Vasoconstriction 
  • Platelets 
  • Coagulation
  • Fibrinolytic system
  • Inhibitor of coagulation.
                                                                                                                                                                     
    Blood Vessels:
  1. Endothelial vessels activate
  2. Produce VAN WELLBRAIN FACTOR.
  3. Clotting Factor
  4. Collagen Exposed
  5. Activates Platelets
  6. Vasoconstriction
  7. Blood Flow Decreases 
    Platelets:
 
    Hemostatic Plug
        1. Adhesion
        2. Aggregation

    Clotting Factor:
    
        There are 13 clotting factors present in the blood, which is produced by the liver, helps in clot formation.

    Coagulation:

        Cascade / Clotting cascade in the pathway.
            1. Intrinsic Pathway
                Activaton of Factor XII (Hageman Factor)
                Contact with damage epithelium (Infected area)

            2.Extrinsic Pathway
               Activation of VII (Stable Factor)
               due to Tissue Injury.                                                                                                                                                          

    I. Fibrinogen
    II. Prothrombin
    III. Tissue Factor
    IV. Calcium
    V. Labile Factor
    VI. There is no factor
    VII. Stable Factor
    VIII. Antihemophilic Factor
    IX. Christmas Factor
    X. Stuart - Power Factor
    XI. Plasma Thromboplastin
    XII. Hageman Factor
    XIII. Fibrin Stabilizing Factor

    Coagulation Regulation Mechanism:
        The activated coagulation system must be limited to the site of injury, to prevent coagulation in the entire vascular system.
        This is achived by 3 endogenous Anticoagulants.
  1. Antithrombin
  2. Protein C and S
  3. Tissue Factor Pathway Inhibitor                  

    Fibrinolytic System:
        Activatiion of the coagulation also initiates Fibrinolytic System, So that the size of the clot is limited.
        Fibrinolytic System removes Fibrin from the clot. Otherwise the clot may progress and involve  the entire circulation.





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