Strokes Flashcards
Head CT is very sensitive to intracranial bleeding/suspected stroke (and even small amounts!) (but an out of clinic- i.e. “I may have had a stroke yesterday but it resolved”- get an MRI)
Signs of stroke: facial drooping, weakness one side of body, time sensitive to tx
Ischemic stroke is the most common cause of stroke (85%- no bleeding)
Causes of stroke: atherosclerosis, embolus, and less common lacunar (attributable to small vessel brain disease; isolated- risk factors: HTN, diabetes)
Cryptogenic/Esus (embolic stroke of uncertain source)= when the cause of stroke is not seen (the longer you wait from onset the less likely you are to find a cause)
Emoblic stroke workout minimum: CT, MRI, CT angiography, 24 hr Holter monitor (if all negative, then ESUS)
If embolic of nature (ie. from a. fib) or ESUS (thought is that a fib is the cause of most of these), need to be on anticoagulation
Blood is less bright than bone
AA are more likely to be on meds for BP= uncontrolled HTN can cause parenhcymal bleeding
Right: bleed due to amyloid
White matter is darker
Air is the darkest, then water, then white matter
Infarct (ischemic stroke) of left MCA (middle)
A stroke is diagnosed by damage on imaging, and no damage = TIA
Can give tPa up to 4.5 hrs
7ml/mg results in neuronal death (calcium influx), lactic acid at 17-19ml/mg
Diffusion weight imagina (DWI) becomes positive within minutes of ischemic insult
IV tPa is the front line tx for stroke to melt the clot (risk of bleeding- need to manage BP to prevent this)
Hypodensity is irreversible!
Now, anyone with a suspected TIA is admission for at least 2 days to determine etiology and prevent 2 day stroke risk
first step upon admission is MRI (CT scan with resolved bleeding will not show symptoms)
A. fib
Lacunar= brain specific small vessel disease
Aminestic stroke= presentation of streoke like symptoms caused by infection, metabolic dirangements, and seizures with no leisons
Range is in megaHz