Disorders of Vasculature & Intracranial Aneurysm Flashcards
*2 types of stroke
ischemic - lack of oxygen
hemorrhagic
how do we classify a stroke or CVA
acute neurologic deficit lasting >24hrs
what is an ischemic stroke
occlusion of artery/interruption of blood flow to the brain
one of the most common neurologic disorders, the most common reason for long-term disability
stroke
what is an hemorrhagic stroke
hemorrhage/bleeding in the brain
which type of stroke has a poorer outcome
hemorrhagic
a stroke can also be referred to as this
brain attack - as serious as a heart attack
strokes have a very high mortality rate, many times from secondary causes t or f
true
non-modifiable risk fxr r/t stroke
thins we cant control (age, family hx, race, gender)
***modifiable risk fxrs r/t stroke
***HTN - single most modifiable risk factor (both types)
smoking - atherosclerosis (hardening of arteries)
heart disease (ischemic strokes) - a lot of plaque in arteries
A FIB
drug abuse (hemorrhagic stroke)
**most modifiable risk factor for strokes
HTN
risk fxr specific to ischemic stroke
heart disease
htn
risk fxr specific to hemorrhagic stroke
drug abuse
patho of ischemic stroke
blood is supplied to the brain by 2 main pairs of arteries, carotid and vertebral
what area of the brain do carotid arteries feed
frontal area
what area of the brain do vertebral arteries feed
posterior circulation
do anterior and posterior cerebral circulation communicate with each other
yes - circle of willis
what allows anterior and posterior cerebral circulation to communicate with each other
circle of willis - re-routes blood
why does the brain require continuous supply of blood to the neurons
it needs glucose and oxygen for neurons to fxn
what happens if blood flow to brain is interrupted
in 30 sec - neurologic metabolism is altered
in 2 min - metabolism stops
in 5 min - cell death occurs
other fxrs affecting blood flow to the brain
ICP
blood viscosity
Systemic BP
what is collateral circulation
Circle of Willis - an area of the brain can receive blood flow from another vessel if original blood supply is cut
one of the primary causes of an ischemic stroke
atherosclerosis in areas where vessels split in 2
when somebody has an ischemic event, occlusion of blood flow to the brain, we will typically see a
pneumbra
*what is a pneumbra?
an area around the ischemia where blood flow circles
*can last for up to 3 hrs.
why is pneumbra a good thing
its preventing further spread of infarction
most common type of stroke
ischemic
3 different types of ischemic strokes
thrombotic
embolic
lacunar
what happens in a thrombotic stroke
injury of blood vessel wall, forming clot, lumen narrows, impeding blood flow to brain mostly in areas of plaque build-up
what happens in a embolic stroke
an embolus lodges and occludes a cerebral artery