stroke Flashcards
can do what in 5 secs of walking in room
ABCs (pt speaking) when did this start? -if woke up with stroke not eligible for tPA -vitals: BP! -oriented/confused -family present
if on coumadin
not candidate for tPA
family can…
sign for tPA consent
verify onset
stroke vs. bells
stroke spares the forehead, can wrinkle
stroke brkdwn
80% ischemic, 20% hemorrhagic
global: low CO (MI, a fib)
focal: occlusion (thrombotic, emolic)
*3rd leading cause of death
strokes can be caused by
emobolism, thrombus,
hypoxic etiologys: hypoperf, or hypoxemia
happens during cerebrovasc. sx: affects watershed areas
risk factors for ischemic stroke
DM HTN smoking fam hx high cholesterol afib drugs (cocaine) hx of TIA or recent MI hx of CHF OCPs
ant. vs posterior circulation
will affect what type stroke
watershed zones: area covered by 2 arteries
ant and mid cerebral aa
post and mid cerebral aa
usually from hypotension
upper leg and upper arm weakness
defects in higher order visual processing
autoregulation
maintains constant level of CBF despite changing perfusion pressure
CPP normally driven by
pCO2, ICP dec. as CO2 dec. via vasoconstriction
- hypervent theory in trauma, CVA*
- can actually cause more damage
hypoxemia will
inc. CPP IF PO2
CPP=
MAP (BP)-ICP
if CPP=0–>brain dead
via blood flow study
a dec. in BP or inc. in ICP results in lowering of CPP
know charts
pg 463
chronic HTN
lower/upper levels of autoreg are raised–>tolerance of higher blood pressures, but more intolerance to lower BP
*used to give clonidine to reduce high BP-won’t stroke out–>but they do from low BP!
now we do NOT abruptly lower BP in asymptomatic chronic HTN pts it’s relative
put on antiHTN, not rapid
cerebral ischemia will lead to
liquefactive necrosis
emo/throm: focal OR
dim. syst: global OR
hypoxia
prolonged ischemia–>infaction
young or old
penumbra
transition zone between normal tissue and infarcted tissue
need to save!
ischemic histo timeline
12-48 hr—red neurons 24-72 hr—necrosis w neutrophils 3-5 days—macrophages (microglia) 1-2 wks—reactive gliosis w vascular proliferation >2ks—glial scar
irrev. damage
after 5 min hypoxia
most vulnerable areas
*hippocampus, neocortex, cerebellum, watershed areas
cerebral edema accumulates..
over 3-5 days after stroke–>death
2/3 ischemic strokes
cerebral atherosclerosis
1/3 ischemic strokes
cardiogenic emboli
afib
patent foramen ovale-DVT
etiology in younger pts: things that make you clot
arterial dissections DRUGS: *cocaine, OCPs(pro-coag), heroin(hypoximic) endocardidtis protein C or S deficiency antithrombin III deficiency anti-PL AB SCD SLE PFO: patent foramen ovale
stroke prevention
control risk factors/reverse them diet smoking HTN-don't take of BP meds DM high cholesterol afib
a fib inc. CVA risk
17x
coum/warf therapy: INR 2-3x basement
Chad’s score/Chad 2 score/Chad vasc score know
-who with a fib need anticoags?
carotid stenosis
> 70% carotid endarterectomy(cleaned out) if high risk–>stunting
60–70% early carotid endarectomy best rather then deferring
TIA
transient neuro deficit
NO infection, neg MRI*
Lasting usually
lacunar stroke
Small lesions
anterior strokes
MCA, ACA, lateral striate, ophthalmic
Ophthalmic artery stroke
amaurosis fugax: sudden vis loss 1 eye, usually transient
ant cerebral art
(Motor and sensory cortex of lower limb)
Weakness + sensory loss contralateral leg
Urinary incontinence possible
Abulia: state of akinetic mutism (inability to make a decision) via B/L frontal lobe dysfunction.
mid cerebral art
embolic typically
contralat wkness loss of sense: face, arm, leg (arm>leg) via motor/sensory cortex lesion
gaze pref AWAY from side of weakness
temporal lobe lesion: Wernicke
frontal lobe lesion: Broca
aphasia if in dominant (typ. left) and hemineglet in nondominant side