Haemostatsis Flashcards
1
Q
What is haemostasis
A
- maintains flowing blood in fluid state and confined to circulatory system
2
Q
What is the most important feature about haemostatic response
A
Localised
3
Q
What happens to blood vessels when injury happens
A
Vasoconstriction
4
Q
What is the primary response driven by
A
- platelets
- endothelial
- fibrinogen
5
Q
What would 1ry response defects cause in
A
- immediate bleeding
6
Q
What is the secondary response driven by
A
- circulating enzymes
- platelets
- fibrin (product of fibrinogen)
7
Q
What would 2ry response defects cause in
A
- delayed bleeding
8
Q
Describe the process of clot forming
A
- collagen exposed —> platelets adhesion
- fibrinogen secretion, ADP & TXA2
- aggregation of molecules
- thrombin formation
9
Q
What does fibrinogen do in clot formation
A
Allows platelets to stick together
10
Q
What is embolisation
A
- broken off clot from thrombin
- highly dangerous
11
Q
Which stage of clot formation do drugs target
A
Secretion
12
Q
What is the mechanism of platelets control
A
Autocrine
13
Q
How come do platelets stick together quickly
A
- large no. of receptors
- high no. of platelets
- rich in signalling proteins
- +ve feedback
14
Q
Describe 1ry response
A
- platelet adhesion
- shape change
- granule release (ADP, TXA2)
- recruitment
- aggregation
15
Q
What are the different shapes of platelets
A
- flowing disc shape
- Rolling ball shape
- hemisphere (firm, reversible adhesion)
- spreading (irreversible adhesion)
