#9 Stroke Flashcards
What is a stroke? What method of brain imaging is used for strokes?
Acute neurological impairment due to brain ischemia or brain hemorrhage (clot that blocks blood flow, or rupture and bleed into brain)
CT/CAT scans are used to image brain when doctors think that they have a stroke
What is the difference in stroke prevalence for men and women?
Men are more likely to have strokes than women at a younger age
Women are more likely to have a stroke than men at older ages
What is an ischemic stroke?
Acute onset of neurological deficits caused by impaired blood flow to the central nervous system, and acute worsening of symptoms indicates a stroke
It is the leading cause of disability with 30% having impaired daily living, 20% with impaired ambulation, and 16% require institutional care
What is the pathophysiology of an ischemic stroke?
Blood flows to the brain through 2 carotid arteries, and 2 vertebral arteries.
Vessel problem: atherosclerosis, vasculitis, dissection, lipohyalinosis
Heart problem: atrial fibrillation, valvular disease, cardiac ischemia
Blood problem: hypercoagulable state that forms clots
Mitochondrial disease
How much blood does the brain need?
50-60 mL/100g/min for normal functioning
20 mL/100g/min for weakness, numb, neurons die but it is reversible
12 mL/100g/min is when you get irreversible damage
What happens to the brain when it is ischemic?
Cellular injury and death: death of neurons, astrocytes, oligodendrocytes, endothelial cells, BBB disruption
Mechanism: apoptosis, autophagy, necrosis, excitotoxicity, inflammation, oxidative stress, ROS, mito dysfunction
What are the two ways that a brain ischemia presents itself?
TIA (transient ischemic attack): complete recovery in 24 hours, no infarct on CT or MRI
Ischemic stroke: persistent neurological deficit for longer than 24 hours, infarct on CT and MRI
Most strokes are caused due to blockage of the middle cerebral artery and results in traditional symptoms.W
What are the arteries an ischemic stroke could result from blockage in?
Middle cerebral artery: traditional stroke
Anterior cerebral artery: leg weakness
What is a lacunar stroke? What is the cause?
stroke resulting in permanent damage, difficult to see on a CT/MRI
Caused by lipohyalinosis: disease of small penetrating arteries, eventually many little arteries get blocked and cause many mini strokes
What are some ways to treat strokes?
Acute stroke management (when they present in the hospital): reperfusion, neuroprotection, prevent complications, rehab
What are some stroke prevention methods
Treat vascular risk factors (hypertension, diabetes, hyperlipidemia, smoking, atrial fibrillation), antiplatelet or anticoagulant, treat underlying cause
What is recanalization?
Time is of the essence, during a stroke 1.9 million neurons are lost per minute. You can use IV TPA to break up the clots, or endovascular therapy
Is there any existing neuroprotection from strokes?
No approved neuroprotective drugs, but preventing hyperglycemia, hypoxia, hypoperfusion and hyperthermia all help
What is TPA?
Tissue plasminogen activator, activates plasminogen to form plasmin which breaks down fibrin based clots, but it breaks down ALL clots so it is a higher risk med.
Absolute benefit of 11-13%, 30% better chance of mild neurologic deficit at 3 months, risk of brain hemorrhage 6.4%
What is endovascular therapy?
Feed catheter into brain with a stent and entangles the blood clot and pulls it out, reduces dead or dependent patients from 71% to 47%
