Pathophysiology of thrombosis and embolism Flashcards
How does blood flow normally?
Laminar (in parallel layers)
What factors affect blood flow?
Pressure gradient Resistance Viscosity of blood Velocity of blood Compliance Composition of blood
What can abnormal blood flow refer to?
Stasis
Turbulence
What is virchow’s triad?
Describes the 3 broad categories of factors that are thought to contribute to thrombosis :
- Hypercoagulability
- Haemodynamic changes
- Endothelial injury/dysfunction
What are the lines of Zahn?
Seen in thrombi: alternating laminations of platelets and fibrin (lighter bands) beside RBCs (darker bands)
Usually seen in clots formed in high flow areas (e.g. heart and aorta) rather than veins or smaller arteries
What are thrombi made up of?
Platelets
RBCs
Fibrin meshwork
What can cause blood stasis?
Long haul flights
Sedentary
Post-op
What can cause blood turbulence?
Atherosclerosis
Aortic aneurysm
What are some important clinical outcomes following thrombus formation?
DVT
Ischaemic limb disease
MI and stroke
Where are systemic thromboemboli more likely to travel to?
Lower limbs most common
Brain
Organs
Where are venous thromboemboli more likely to travel to?
Pulmonary arterial circulation
What causes decompression sickness?
N2 forms as a bubble (embolus) and lodges in capillaries
