Secondary Hemostasis Flashcards
True or False:
Extrinsic Tenase Complex can activate Factor IX
True
Vitamin K-Dependent Coagulation Factors:
*Factor II
*Factor VII
*Factor IX
*Factor X
*Protein C
*Protein S
*Protein Z
The coagulation factors have been described as reacting in a:
Cascading sequence
3 pathways of Coagulation cascade
Intrinsic, Extrinsic, Common pathways
Most significant substrate:
Factor I - Fibrinogen –> Fibrin
A stable protein factor that is neither consumed during clotting nor destroyed by aging at 4deg Celsius for 2 weeks
Factor IX - Plasma Thromboplastin Component
HMWK is also known as:
High-molecular weight kininogen/Fitzgerald factor
Necessary for the activation of thromboplastin and for the conversion of prothrombin to thrombin
Factor IV - Ionized Calcium
No fibrinogen group. Still contains 20% OF Factor II
Serum
Hasten the reaction of enzymes
Co-factor
Derived from
phospholipoproteins and organelle membranes from disrupted tissue cells
Tissue thromboplastin
Bleeding from small blood vessels may be stopped by _____ and the ____________.
may be stopped by Vasoconstriction and the formation of a platelet plug.
Factor XI
Plasma thromboplastin antecedent
Antihemophilic factor can be falsely decreased in the presence of:
Lupus anticoagulant (LA)
These are critical components in the formation of a thrombus
Soluble blood coagulation factors
Classification based on Physical Properties:
*Contact group
*Vitamin K dependent Prothrombin group
*Fibrinogen group
A proteolytic enzyme, which interacts with fibrinogen
Factor IIa - Thrombin
True or False:
All coagulation factors normally are present in the serum
False - They are normally present in the plasma
Factor X
Stuart Factor/Stuart-Prower factor
True or False:
Without the presence of Factor XII, Factor IX cannot be activated
False - Even without the presence of Factor XII, Factor IX can still be activated
Release of tissue factor from damaged vessel
Extrinsic Pathway
Leads to secondary hemostasis, the formation of stable fibrin clot
Common pathway
Has presence of serine in the active site; synthesized as inactive zymogens
Serine protease enzyme
Derived from tissue that surrounds the vessel
Factor III (Tissue Thromboplastin)
A beta-globulin and not an essential component of the intrinsic thromboplastin-generating mechanism
Factor VII - Proconvertin
True or False
The factor can be assayed in the laboratory
True
An acute-phase reactant, consumed during the clotting process and is NOT FOUND in serum.
Factor VIII - Antihemophilic Factor
Derived from diet
Factor IV (Ionized Calcium)
How many clotting factors?
14 clotting factors
A stable protein with a MW of 63,000
Factor II - Prothrombin
Precursor of fibrin, which form the resulting clot
Factor I - Fibrinogen
Factor I
Fibrinogen
True or False:
Deficiencies of Factor XI, IX, VIII, VII, X, V, Prothrombin (II), and Fibrinogen (I) are clinically significant
True
Other cells, like _______, also play an important role in the normal process of hemostasis and thrombosis
Endothelial cells
Group that is absent or not found in serum
Group 1 - Fibrinogen group
Prekallikrein is also known as:
Fletcher factor
Classification based on Function:
*Substrate
*Co-factor
*Enzyme
A potent platelet-aggregating substance, consumed during the process of converting fibrinogen to fibrin.
Factor IIa - Thrombin
Necessary for the activation of factor
IX by factor XIa
Calcium
Factor II
Prothrombin
The activated form of prothrombin with a MW of 40,000
Factor IIa - Thrombin
Activated once they come in contact with a negative charge
Contact group
Alpha-globulin, is a relatively stable factor that is not consumed during clotting
Factor X - Stuart factor
Reduced by Vitamin K antagonists
Factor VII - Proconvertin
This factor, in the presence of ionized calcium, produces a stabilized fibrin clot.
Factor XIII - Fibrin-Stabilizing Factor
Designed to stabilize the plug
Secondary Hemostasis
Vitamin K Antagonists:
*Coumadin
*Warfarin
They act as an enzyme and circulates in the body (plasma) inactively EXCEPT for Factor III (only inside tissue) & IV (inside the platelet)
Clotting factors
Catalyzes the transfer of amino group to Factor XIII
Transglutaminase
What is the source of negative charge in IN VITRO?
Glass surface
Results in the formation of a stable fibrin clot
Secondary Hemostasis
An essential component of the intrinsic thromboplastin generating system, where it influences the amount rather than the rate of thromboplastin formation
Factor IX - Plasma Thromboplastin Component
These monomers ______ together to form the final polymerized fibrin clot
Aggregate
A stable factor that is not consumed during the coagulation process
Factor XII - Hageman factor
Co-factors:
*Factor III - Tissue Factor
*Factor V - Proaccelerin
*Factor VIII - Antihemophilic Factor
*HMWK
*Thrombomodulin
*Protein S
*Protein Z
True or False:
The Physical and chemical characteristics of the factor are known
True
Inhibitors and procoagulants are from:
Liver
Physiologically active form of calcium in the human body, and small amounts are needed for blood coagulation
Ionized Calcium
True or False:
The synthesis of the factor is dependent of other proteins
False - it is INDEPENDENT of other proteins
Can be falsely decreased in the presence of lupus anticoagulant
Factor VIII - Antihemophilic factor
VWF
von Willebrand Factor
When fibrinogen is exposed to thrombin, how many peptides split from the fibrinogen molecule, leaving a fibrin monomer?
Two peptides
Factor V
Proaccelerin/Labile Factor
involves the contact activation factors prekallikrein,
HMWK, factor XII, and factor XI
Intrinsic coagulation pathway
Factor IIa
Thrombin
Clotting factors under Vitamin K Prothrombin group:
Factor II, VII, IX, X
Factor XII
Hageman factor
Activated by release of TF III
Extrinsic Pathway
Together with factor V, this factor, in the presence if calcium ions forms the final common pathway.
Factor X - Stuart Factor
Deteriorates rapidly, having a half-life of 16 hours and is consumed in the clotting process.
Factor V - Proaccelerin
These are labile
Factor V and VIII
Activation of extrinsic and intrinsic pathway
Common Pathway
Factor VII
Proconvertin/Stable factor
What are the 3 groups of Coagulation Factors?
*Group I=Fibrinogen group - (I, V, VIII, XIII)
*Group II=Prothrombin group - (II, VII, IX, X)
*Group III=Contact group - (XI, XII, Fletcher factor/Prekallikrein, Fitzgerald factor/HMWK)
Extremely labile, with a 50% loss within 12 hours at 4deg Celsius in vitro and a similar 50% loss in vivo within 8-12 hours after transfusion
Factor VIII - Antihemophilic factor
A large, stable globulin protein with a MW of 341,000
Factor I - Fibrinogen
Regulatory proteins that are vitamin K dependent:
Proteins C, S, Z
A deficiency of the factor generally produces a bleeding tendency disorder with the EXCEPTION of what factors?
*Factor X11
*Prekallikrein (Fletcher factor)
*High-molecular weight kininogen (HMWK/Fitzgerald factor)
Initiated by the entry of tissue thromboplastin into
the circulating blood
Extrinsic Coagulation Pathway
The activity of Factor X appears to be related to what factor?
Factor VII - Proconvertin
Clotting factors under the Contact group:
Factor XII, XI, HMWK, Prekallikrein
In the presence of this factor, prothrombin is converted to thrombin by the enzymatic action of thromboplastin from both extrinsic and intrinsic sources.
Factor IV - Ionized calcium
Plasma Procoagulant Serine Cofactors:
*Tissue Factor
*Factor V
*Factor VIII
*HMWK
Principal site of the synthesis of coagulation factors:
Hepatic cells
Half-life of almost 3 days with 70% consumption during clotting
Factor II - Prothrombin
These factors are consumed whenever formed a clot. They are part of the clot together with 80% of Factor II
Factor I, V, VIII, XIII
Therapeutic inhibitor of vitamin K
Coumadin
Coagulation Factors under Prothrombin group:
Factors II, VII, IX, X
Platelet factor III
Phospholipids, phosphatidyl-serine, PF3
Tissue thromboplastin is derived from:
Phospholipoproteins and organelle membranes from disrupted tissue cells
Acts as a substrate to another clotting factor to facilitate clotting
Substrate
Factor IX
Plasma thromboplastin component/Christmas factor
Plasma Procoagulant Serine Proteases:
*Factor II
*Factor VII
*Factor IX
*Factor X
*Factor XI
*Factor XII
*Prekallikrein
Essential to the later stages of thromboplastin formation
Factor V - Proaccelerin
An extremely labile globulin protein
Factor V - Proaccelerin
True or False:
Extrinsic and Intrinsic pathway are both happening simultaneously
True
Factor VIII
Antihemophilic Factor
Interaction of the plasma clotting factors to form a stabilize/stable fibrin clot/fibrin mesh
Secondary Hemostasis
Formation of fibrin through the coagulation cascade
Secondary Hemostasis
Activated by exposure of collagen
Intrinsic Pathway
Pertains to any non-plasma substance containing lipoprotein complex from tissues (Brain, Lung, Vascular Endothelium, Liver, Placenta or Kidneys).
Factor III - Tissue Thromboplastin
In IN VIVO, what is the source of negative charge that would activate the clotting factor?
Collagen
Not destroyed nor consumed in clotting process and is found in both plasma and serum, even in serum left at room temperature for up to 3 days
Factor VII - Proconvertin
Factor XIII
Fibrin-stabilizing factor
A beta-globulin, can be found in serum because it is only partially consumed during the clotting process
Factor XI - Plasma Thromboplastin Antecedent
A deficiency of the factor generally produces a bleeding tendency disorder with the EXCEPTION of these factors:
*Factor XII
*Prekallikrein (Fletcher factor)
*HMWK (Fitzgerald factor)
Most complex labile, exists in different forms
Factor VIII
Essential to the intrinsic thromboplastin-generating mechanism
Factor XI - Plasma Thromboplastin Antecedent
True or False:
Deficiency of Factor XII, and the presence of the Lupus anticoagulant are clinically significant for bleeding
False - Deficiency of Factor XII, and the presence of the Lupus anticoagulant are NOT clinically significant for bleeding
Coagulation Factors under Contact group:
Factors XI, XII, Prekallikrein/Fletcher factor, High-molecular weight kininogen/HMWK/Fitzgerald factor
Activated by contact of certain coagulation protein with the subendothelial CT
Intrinsic Pathway
These tissue types are capable of converting Prothrombin to Thrombin
Brain, Lung, Vascular Endothelium, Liver, Placenta or Kidney
Factor III
Tissue thromboplastin/Tissue factor
Coagulation Factors under Fibrinogen group:
Factors I, V, VII, XIII
These factors require vitamin K for carboxylation of glutamic acid of clotting factors
Factor II, VII, IX, X
All clotting factors are produced in the liver EXCEPT:
Factor III & IV
Factor IV
Ionic calcium