Pathophysiology of thrombosis and embolism (part1) Flashcards
What is normal blood flow?
laminar
Describe laminar blood flow
smooth and ordered
What is the arrangement of plasma and cells in laminar blood?
cells in centre and plasma around the outside, in contact with the endothelial surface
What affects the bodies vascular system?
pressure gradient (arterial to venous)
resistance (increase or decrease in vessel diameter)
viscosity of blood
velocity
compliance (of the vessel, type of vessel)
What are 2 types of abnormal blood flow?
STASIS
TURBULENCE
What is STASIS blood flow?
stagnation in blood flow
What is turbulence blood flow?
forceful unpredictable flow
What are causes defects in blood flow?
thromboembolism common
also…
atheroma
hyperviscosity, spasm, external compression, vasculitis, vascular steal
What is atheroma?
the fatty material that clogs your arteries
What are the components of Virchows triad?
changes in the blood vessel wall
changes in the blood constituents
changes in the pattern of blood flow
What does virchows triad show?
factors causing thrombosis
What is thrombosis?
formation of solid mass form the constituents of blood within the vascular system during life
thrombosis vs thrombus?
thrombosis is the process
thrombus is what is formed
thrombus vs clot?
clot = in vitro or post death
thrombis = in vivo living
What is a good example of a change in the vessel wall (thrombosis)?
atheromatous coronary artery
Layers of a blood vessel?
intima
media
adventitia
What happens in the pathogenesis of thrombosis?
endothelial injury
stasis or turbulent blood flow
hypercoagulability of the blood
(virchows triad)
describe the pathogenesis of thrombosis?
- normal clear artery
- atheromatous plaque develops
- turbulent flow due to the atheromatous plaque
- turbulent flow causing damage and loss of endothelial surface - exposes the sticky collagen of the plaque and to the flowing blood
- causes elements of the flowing blood to be stick to the exposed plaque
this causes a sloid mass called thrombus
What can happen due to turbulanet flow?
firnbin deposition, plateles clumping
What can the fibrin meshwork and trapped RBC be called?
lines of Zahn
What is the most important risk factor for atheroma?
hypercholesterolaemia
(virchows triad)
propagates?
gets bigger
What is another example of a change in vessel wall?
change in heart
What are examples of changes in blood constituents (thrombosis)?
hyperviscosity, post-traumatic hypercoagulability
What are examples of STASIS?
economy class syndrome (not moving legs)
post-op
= deep vein thrombosis
What are examples of thrombosis caused by turbulence?
atheroatous plaque, aortic aneurysm
What do the consequences of thrombosis depend on?
site
extent
collateral circulation
What are common clinical scenarios?
DVT
ischemia limb
MI
