Thrombosis, Embolism & Shock Flashcards
What is blood clotting an example of?
Haemostatis
What is haemostatis?
The balance between maintaining blood clotting function and the loss of blood. it requires anti-coagulant factors and pro-coagulant factors
What is the process of blood clotting?
1) Damage to the endothelium
2) Vasodilation
3) Platelets adhere, active and aggregation
4) Primary platelet plug is formed
5) Clotting factors are activated due to collagen exposure
5) The final stage of the clotting factor cascade causes the stable fibrin clot
Why would you want to limit coagulation at the site of injury?
Prolonged clotting will cause thrombosis
What factors limit coagulation?
1) Clotting factors are only activated once collagen is exposed
2) Anti-thrombin factors
3) Protein C and S will inactive some clotting factors
4) Plasmin performs fibrinolysis
How is blood clotting measured?
INR (international normalised ratio)/ Prothrombin time
What is the normal INR/Prothrombin time?
1 - 1.5
What causes an increase in INR/Prothrombin time (longer for blood to clot)?
1) Vitamin K deficiency
2) Malabsorption
3) Liver disease
4) Warfarin Therapy
5) Increased consumption of clotting factors
Definition of thrombosis?
The process of the inappropriate activation of blood clotting resulting in a thrombus
Definition of thrombus?
A semi-solid or solid mass containing blood constituents (at the primary site)
Definition of emboli?
Any detached intravascular solid, liquid or gas travelling in a vessel to a secondary site distant from the primary site
Definition of a Thromboemboli?
A fragment of the thrombus which causes an emboli in a distant site to its primary site
What 3 factors increase the likelihood of a thrombus?
VIRCHOW’S TRIAD:
1) Abnormalities in the endothelial wall
2) Abnormalities in the blood flow
3) Abnormalities in the blood constituents
How can a thrombus be detected?
Using an echocardiogram
What are the 2 types of thrombus?
Mural and Ball thombus
What causes a mural thrombus?
Rheumatic endocarditis = Inflammatory condition of the heart