Flashcards in Bleeding and hemostasis Deck (19)
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1
Primary hemostasis?
Platelets and sub-endothelial collagen react to form a platelet plug
2
Secondary hemostasis?
Coagulation factors react to form fibrin polymers that stabilize the platelet plug (from primary) to form a mature thrombus
3
Fibrinolysis
dissolution of the fibrin clot
4
Platelets
From megakaryocyte in BM
Release at about 10 to the 11 per day
Live about 6-8 days
When activated makes TxA2 cox-1 mediated. Major platelet aggregation factor
5
Platelet adherence to sub endo collagen - via...
platelet glycoprotein VI receptor or
vWf via glycoprotein Ib receptor
6
3 overlapping phases of cell based model of coagulation
Initiation, amplification, propagation
7
What cell(s) involved with initiation?
Tissue factor (TF) bearing cells
8
What coagulation factors are involved with initiation?
7, TF, 10, 9, 5, and a small amount of 2a(thrombin)
9
Whats the end result of initiation?
Small amount of thrombin (2a) is formed which activates local platelets
Activated factor 9 (9a) is released
10
What cell(s) involved with amplification?
Platelets
11
What coagulation factors are involved with amplification
2,5,8,
12
Whats the end result of amplification
activated platelet with 5a and 8a attached
13
What cell(s) involved with propagation
activated platelet
14
Whats end result of propagation
Lots of thrombin
15
2 places thrombin is formed
Small amount on TF bearing cells
Large amount on activated platelets
16
Thrombin activities
activates - platelets, factors 5, 8 (cleaving off vWf in the process), 11, cleaves fibrinogen to fibrin
17
TF/VIIa complex: where is it and whats it do?
on TF bearing cells and activates 9 and 10
18
9a/8a
on activated platelets and activates 10
19
