Principles of coagulation Flashcards
When there is injury to a blood vessel what happens before the formation of the primary hemostatic plug?
vasoconstriction
Why does a blood vessel constrict immediately after injury?
to slow down the blood and allows all the coagulation factors time to interact
What clotting factor deficiency does a pt possibly have if s/he has:
normal PT and prolong PTT
8, 9, 11, 12, prekalikrein, HMWK
What clotting factor deficieincy does a pt possibly have if s/he has:
normal PT and prolong PTT and is bleeding
8, 9, 11 (or vWF)
What clotting factor deficieincy does a pt possibly have if s/he has:
normal PT and prolong PTT, is bleeding, low factor VIII
hemophilia or vWF deficiency
What clotting factor deficieincy does a pt possibly have if s/he has:
normal PT and prolong PTT, is bleeding, low factor VIII, low vWF
vWF deficiency
What clotting factor deficieincy does a pt possibly have if s/he has:
normal PT and prolong PTT, is bleeding, low factor VIII, normal vWF
hemophilia
What clotting factor deficieincy does a pt possibly have if s/he has:
normal PT and normal PTT and pt is still bleeding
factor XIII deficiency
What clotting factor deficieincy does a pt possibly have if s/he has:
prolong PT and normal PTT
7 deficiency
What factors are measured with PT?
7, 5, 10, prothrombin (2), fibrinogen
- extrinsic pathway
What factors are measured with PTT?
everything but 7 (and 13)
*intrinsic
What clotting factor deficiency does a pt possibly have if s/he has:
prolong PT and prolong PTT
10, 5, prothrombin (is this right?)
T or F: antithrombic counter regulation occurs only after the formation on the secondary hemostatic clot
F: it occurs the entire time a clot is forming
What clotting factors are serine proteases?
11, 9, 7, prothrombin (2)
What clotting factors are cofactors?
12, 8, 5, tissue factor (3)
What are the vitamin K dependent clotting factors?
2, 7, 9, 10
protein S and C
What is the role of vitamin K in the activity of some of the clotting factors?
it is needed for the carboxylation of glutamic acid residues. Without the carboxylation, these clotting factors canot adhere to the a phospholipid membrane
Elevated F1.2 indicates….
elevated thrombin (bc active thrombin makes F1.2)
What does von Willebrand’s disease and hemophilia have in common?
low factor 8
Where is factor 8 made? What is it bound to?
made in the liver
bound to vWF
If a pt does not have vWF, they will have (high, low) factor 8
low
What molecule antagonizes thrombin?
anti-thrombin 3
How does heparin effect anti-thrombin 3?
changes the shape of anti-thrombin 3 so that it binds up/inhibits thrombin
What does active protein C do?
inactivates 5a and 8a (stops clot formation) inactivates tPAi (enhances fibrinolysis)
How does protein C become active?
thrombin binds thromodulin on endothelial surface. This interaction activates protein C (which was bound to a receptor on endothelial surface and released upon activation)
What does thrombin cleave off of fibrinogen to make fibrin?
fibrinopeptide A and B
What is a D dimer?
product of fibrin cleavage by plasmin
fibrin degradation product
T or F: a fibrin degradation product can still form a weak clot
T (fragment Y)
T or F: a fibrin degredation product has the ability to negatively regulates clot formation
T: fragment D can inhibit platelets bc they bind it thinking it is fibrin
What holds a fibrin polymer together?
Hydrogen bonds
What activates factor 13?
thrombin
What is the role of clotting factor 13?
crosslinks fibrin polymers with transaminase bonding
T or F: Plasmin is circulating freely in our blood
F: it if formed on a fibrin clot
How is plasminogen converted to plasmin?
Tissue Plasminogen Activator (TPA) is a serine protease that binds fibrin to activate plasmin locally at the clot
What is the role of alpha-2 plasmin inhibitor?
inhibits any local free plasmin (keeps it from getting into circulation)
What are the factors involved in the intrinsic activation of plasminogen to plasmin?
12a and Kallikrein
What are the factors involved in the extrinsic activation of plasminogen to plasmin?
tPA
urokinase-like A
What is streptokinase?
bacterial agent/peptide that complexes with plasminogen which converts other molecules to plasmin
What does tissue factor do?
initiate coagulation (extrinsic)
What does PGI2 (prostacyclin) do?
vasodilation and inhibit platelet aggregation (activates adenylate cyclase to inc cAMP)
What does vWF do?
platelet-collagen adhesion
carriage of factor 8
What does protein C and S do?>
inhib coag
WHat does TPA do?
fibrinolysis
What does alpha1-protease inhibitor act on?
factor 11a to prevent activation of 9
What does antithrombin/heparin act on?
9a to prevent formation of Xa
What does TFPI-Xa act on?
TF-7a to inhibit Xa and 9a formation
What does alpha2-macroglobulin act on?
thrombin
What does heparin cofactor II act on?
thrombin
