neuro pt1 Flashcards
how much does the brain consume
25% of body’s oxygen
25% of body’s nutrients
70% of body’s glucose
what does 1-60 seconds of no blood flow to the brain cause
loss of conciousness
what does 2-4 seconds of no blood flow to the brain cause
glycogen and glucose stores are exhausted
what does 4-5 minutes of no blood flow to the brain cause
cellular ATP stores are fully depleted, brain damage likely
what does 6-10 minutes of no blood flow to the brain cause
brain damage is likely
what does 10+ minutes of no blood flow to the brain cause
irreversible brain damage (biological death)
what are the four types of brain insults
ischemia insults
acute insults
increased intercranial pressure (insults)
degenerative disorders (insults)
what is global ischemia
blood flow cannot meet metabolic demands (cardiac arrest, shock, asphyxiation)
to entire brain
what is focal ischemia
ischemia to one focal or specific portion of the brain (strokes)
true or false: 25% of strokes happen in people with history of previous strokes
true
what are the categories of ischemic strokes
thrombus (disease)
embolisms (clots)
hypoxia (an event)
what is a hemorrhagic stroke categorized as? idk
primary brain bleed
how many internal carotid arteries are there and where are they located
two
come up laterally from the front of the neck, branch off into two terminal arteries
what do the external carotid arteries do
supply blood to the neck and face
how many vertebral arteries are there and where are they located
two
come up laterally along the spine and near the back of the neck
what do vertebral arteries do
supplies blood to the brain stem and, cerebella and occipital lobes
the two vertebral arteries come together and form what
basilar arteries
what arteries anastomose (join) each other at the base of the brain and what does it form
basilar and internal carotid arteries
forms circle of willis
what does the circle of willis connect
anterior posterior brain circulation
(if one artery is damaged, blood flow is usually not compromised)
what is a thrombolytic stroke
most common of ischemic strokes
local action
build up of plaque
atherosclerosis (carotids/vertebral)
what is an embolic stroke
clot originates somewhere in the body and travels to the brain
may be secondary to thrombotic stroke (embolus detached from primary site of stroke)
what is a large vessel thrombotic occlusion (LVO)/strokes
large vessel disease (atherosclerosis)
counts for 20% of ischemic strokes
symptoms vary with location
what are “occlusions” but not necessarily clots yet
middle cerebral artery (MCA) most common
anterior cerebral artery (ACA) least common
posterior cerebral artery (PCA)
vertebral/basilar (basilar) artery
what is a cerebral “small vessel disease”/thrombotic stroke
25% of ischemic strokes
small arteries sometimes called small strokes or lacunar infarctions
usually small and deep
closely linked to hypertension
likely a form of atherosclerosis
“white matter hyperintensity” or “white matter disease”
what do cerebral “small vessel disease”/thrombotic strokes cause
loss of function
disability
age-related cognitive decline related to dementia, strokes, motor movement issues (old)
what is a transient ischemic attack (TIA)
“short-lives/passing/temporary” form of brain ischemia
symptoms caused by cellular hypoxia without cellular death, thus NOT a “mini stroke”
warning sign of a real stroke
15% experience full strokes within 3 months
what is a warning sign of transient ischemic attack (TIA)
hypoxia without severe damage
what are the cardiogenic sources of ischemic strokes
20%
atrial fibrillation
myocardial infarction
endocarditis
other dysrhythmias
what are the other and unusual (unknown) causes of ischemic strokes
35%
vasospasm after subarachnoid hemorrhage
cerebral vasoconstriction syndromes
radiation-induced vasculopathy
air or fat embolisms
amniotic fluid following childbirth
tumors
unknown
true or false: in the acute stages a stroke is stagnant
false: it is evolving, will not know true outcomes for person for days/weeks
what are the causes and risk factors for ischemic strokes
• Like cardiovascular disease
• Uncontrolled HTN
• Smoking
• Heart disease/atherosclerosis
• Diabetes
• Atrial fibrillation
• Carotid artery disease/stenosis
• Hyperlipidemia
• Physical inactivity/obesity
• Eclampsia in pregnancy
what is a hemorrhagic stroke
burst of blood vessel may allow blood to seep into and damage brain tissues until clotting shuts off the leak
what is the process of a brain hemorrhage
- Rupture of a blood vessel (aneurysm?)
- Bleeding goes into the brain (location matters)
- Creates a focal hematoma that may get larger,
- The brain swells
- Brain matter gets compressed
- coma/death
what are the symptoms of a hemorrhagic stroke
Person feels a “thunderclap headache”
Contralateral hemiplegia
Leads to spasticity
Loss of consciousness
Increased intracranial pressure
Coma/posturing/death (without treatment)
what do primary injuries of strokes result from
compression by the hematoma
increase in the intracranial pressure