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Flashcards in Bleeding and hemostasis Deck (19):
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

10a/5a

on TF bearing cells and activated platelets
Cleaves prothrombin to thrombin