Intro & Pathophysiology of CVA Flashcards
stroke
sudden cessation of cerebral blood flow leading to oxygen-glucose deprivation through blockage or hemorrhage
what is the leading cause of serious long-term neurological disability
stroke
modifiable risks
- things we can change
- HTN, diabetes, CV disease, obestiy, obstructive sleep apnea, physical inactivity, diet, blood disorders, arrhythmias, hyperglycemia, smoking, alcohol, drugs
non-modifiable risk
- things we cant change
- women > men
- 55 years old
- black/hispanic, american indian, alaskan natives
- prior stroke, TIA and/or MI
- genetics
women > men
- 55,000 more females have a stroke than males
- higher lifetime risk
when you’re older..
incidence doubles >55 years old
race risk factors
- black/hispanic:white - 2:1 ratio –> increases to 4:1 btw ages 45-54
- american indian and alaskan natives are at high risk too
prior stroke, TIA, and/or MI
23% of people will have a second stroke
HTN risk factor
1 most common and most modifiable risk factor for stroke
arrhythmias risk factor
increases CVA risk 5x
ischemic strokes (cerebral infarct) cause
diminished volume of perfusion
cause: gradual worsening of fatty deposits lining arterial walls (atherosclerosis)
thrombotic
blockage caused by clot form within involved artery - occur anywhere
embolic
blockage caused by clot that travels from elsewhere in circulatory
smaller arteries
hemorrhagic strokes cause
rupture of artery due to weakening of vessel wall
intracerebral hemorrhage (ICH)
most common
cause: HTN
subarachnoid hemorrhage (SAH) cause
- aneurysm and arteriovenous malformation (AVM)
aneurysm
enlargement/ballooning of weakened vessel wall
AVM
tangle of abnormal blood vessels connecting arteries and veins
transient ischemic attack TIA
- transiet episode of neurological dysfunction caused by focal brain, spinal cord or retinal ischemia without infarction
- mini stroke, warning stroke
- symptoms last < 24 hrs
in the ischemic cascade, the infarct core experiences
necrosis
in the ischemic cascade, the penumbra experiences
apoptosis
in the ischemic cascade, what happens within minutes
neuronal death in core
in the ischemic cascade, what happens within hours
surrounding tissue (penumbra) death
onset of symptoms for a thrombotic event
- gradual onset
- days to weeks
- most common in late PM or first thing AM, may see “wake up strokes”
onset of symptoms for a embolic event
more abrupt than thrombotic
minutes to hours
onset of symptoms for a hemorrhagic event
- aneurysm
- AVM
- immediate, severe
- asymptomatic until rupture
- may have preceding symptoms (seizures, etc)
onset of symptoms for a hemorrhagic event
- aneurysm
- AVM
- immediate, severe
- asymptomatic until rupture
- may have preceding symptoms (seizures, etc)
common complaints of CVA
- imbalance
- paraesthesias
- weakness
- blurry or double vision
- “worse HA of my life”
national institutes of health stroke scale (NIHSS)
- quantitative measure of symptoms associated with cerebral infarcts
- 15 items –> consciousness, vision, motor & coordination, sensory & perception, language & fluency, behavior
cut off scores for NIHSS
> 25: very severe –> frequently require long term skilled care
15-24: severe –> frequently require long term skilled care
5-14: mild to moderatly severe –> typically require acute pt rehab
1-5: mild –> 80% will be discharge home from acute hospital
when should a pt get a CT
- head trauma
- financial concerns
- acute hemorrhage
- speed needed
- skull fx
- calcified lesion
- claustrophobic pt
- pacemaker or other metallic implant
when should a pt get a MRI
- subtle areas of tumor, infarct, demyelination, etc.
- brainstem lesion
- ischemia
- subacute or chronic hemorrhage
- anatomy detail needed
ischemia stroke major goal
revascularization
management of an ischemia stroke
- tPA –> 3-8 hr window
- permissive HTN –> <220/110
- antiplatelets for first 24-48 hours –> aspirin
major goal for hemorrhagic stroke
reduce intracranial pressure (ICP)
sedation, hyperosmolar agents, hyperventilation
management for hemorrhagic stroke
- anti-hypertensive for BP control –> strict BP parameters, <130/80
- vasospasm prevention and management (SAH)
- antiseizure prophylaxis (ICH)
if a pt has increased intracranial pressure, what are the PT considerations
- monitor for S&S of increase ICP
- avoid activity that may exacerbate
- mobility contraindicated if >20mmHg
if pt has a midline shift, what are PT considerations
- evaluate bilateral symptoms
- monitor closely for neurological decline
if pt has brain herniation, what are PT considerations
PT usually not indicated
what is a vasospasm
persistent vasoconstriction and dilation of the blood vessels
PT considerations for vasospasm
mobility contraindicated with moderate to severe vasospasm - consult MD prior to mobility
seizures PT considerations
mobility usually deferred until > 24 hr after quiet EEG, monitor closely for seizure activity
what are additional acute CVA complications
- HTN
- fever
- pressure ulcers
- infection
- pneumonia
- hyperglycemia
