Haemostasis, Haemorrhage, & Shock Flashcards
1
Q
What is haemostasis?
A
The body’s physiological response to stop bleeding of a blood vessel?
2
Q
What is a haemorrhage?
A
An escape of blood from a ruptured blood vessel
3
Q
What are the 3 components involved in haemostasis?
A
- Vascular response
- Platelet response
- Plasma response (coagulation)
4
Q
What happens in the vascular response of haemostasis?
A
- Smooth muscle contracts to reduce blood flow
- Endothelium allows for platelet adhesion and aggregation
5
Q
What happens in the platelet response of haemostasis?
A
- Platelets contact vessel wall and adhere & aggregate.
- Release chemicals which cause further aggregation which results in formation of a platelet plug - effective for sealing small blood vessels
6
Q
What happens in the plasma response (Coagulation) of haemostasis?
A
- Conversion fibrinogen -> fibrin to form clot
- Numerous clotting factors involved (produced in liver, Vit K required)
- The clotting factors are activated in an enzyme cascade
7
Q
What is fibrinolysis and when does it occur?
A
Fibrin breakdown by enzymes
When clot served purpose, dissolved by enzyme plasmin
8
Q
What is shock?
A
Shock is a life threatening condition that occurs when the body is NOT getting enough blood flow
9
Q
What are some types of shock?
A
- Hypovolemic shock (occurs when more than 20% of blood volume is lost, not enough volume to provide entire body)
- Cardiogenic shock (heart fails as pump)
