Hemostasis Flashcards
thrombus
stationary clot on blood vessel wall
embolus
clot that detaches from site of origin and travels
Coagulation Factor II
Thrombin
Describe what occurs in primary hemostasis and what clotting factor is involved, and what is its function. What coagulation tests can be used to assess it?
First, vasoconstriction. Platelet activation, adhesion, and aggregation. Von Willebrand’s Factor helps platelet plug adhere.
BMBT
Describe secondary hemostasis and name the tests that can assess it
cascade of enzyme conversions lead to the formation of fibrin and the stabilization of the platelet plug.
PT and PTT
(prothrombin time and partial thromboplastin time)
Products of fibrinolysis? What performs it, and what is it activated by?
FDP and d-dimers
Tissue Plasminogen Activator
plasminogen -> plasmin
hydrolysis of fibrin. FDP also has anti hemostatic properties
where are most clotting factors synthesized? name an exception
the liver
tissue thromboplastin
what is factor XIII important for?
stabilizing cross-linked fibrin strands
what mineral is important in clotting
calcium
describe what happens in the extrinsic pathway
factor VII and tissue thromboplastin (both found in subendothelial adventitial cells) form a complex. “tissue thromboplastin activated factor VII complex”. Lead to the activation of factor IX and X
what is factor XII associated with? what is it activated by?
assoc with thrombi growth
wet anionic surfaces activate it
thrombocyte lifespan?c describe their general appearance
4-6 days
small round to oval anucleated cell fragments (non-mammals have nuclei)
thrombocyte precursor?
megakaryocyte
normal thrombocyte count?
what would constitute thrombocytopenia?
when would clinical signs of hemorrhaging appear?
200k-500k cells/microliter
<50k cells/microliter
normal platelet count for avians?
20-30k cells/microliter
