stroke Flashcards
CNS infarction
brain, spinal cord, or retinal cell death due to ischemia
ischemia
limited or loss of blood flow
what evidence do you need for CNS infarction
pathological/imaging/objective evidence of cerebral, spinal cord, or retinal focal ischemic injury in a defined vascular distribution, or clinical evidence of cerebral, spinal cord, or retinal focal ischemic injury based on symptoms persisting >24 hours or until death, and other pathologies excluded
silent CNS infarction
imaging or neuropathologic evidence of CNS infarction, without a history of acute neurological dysfunction attributable to the lesion
ischemic stroke
an episode of neurological dysfunction caused by focal cerebral, spinal, or retinal infarction
transient ischemic attack (“mini stroke”)
a transient episode of neurological dysfunction caused by focal cerebral, spinal, or retinal ischemia without acute infarction, typically lasting <1 hour (10% risk of stroke within 7 days)
intracranial hemorrhage
a focal collection of blood within the brain parenchyma or ventricular system, not due to trauma (includes parenchymal hemorrhage after CNS infarction)
stroke due to ICH
rapidly developing signs of neurologic dysfunction due to a focal collection of blood within the brain parenchyma or ventricular system, not due to trauma
subarachnoid hemorrhage
bleeding into the subarachnoid space (space btwn the arachnoid membrane and the pia matter of the brain or spinal cord)
stroke due to SAH
rapidly developing signs of neurologic dysfunction and/or headache due to subarachnoid hemorrhage, not caused by trauma
__% of strokes are ischemic
87
__% of strokes are hemorrhagic
10
_% of strokes are due to SAH
3
how can you tell the difference between hemorrhagic and ischemic stroke
dark is dead, white is blood
in a ______ stroke, hemorrhage/blood leaks into brain tissue
hemorrhagic
in a ____ stroke, a clot stops blood supply to an area of the brain
ischemic
modifiable risk factors for stroke
cigarette smoking, HTN, DM, dyslipidemia, AFib, carotid stenosis, structural heart disease, poor diet, obesity, physical inactivity
non-modifiable risk factors for stroke
age, family history, race, sex, prior stroke/MI/TIA
what is the time dependent cascade of ischemic changes in stroke
decreased energy production, increased glutamate receptors, increased intracellular Na, Cl, Ca, mitochondrial injury, cell death
the severity of injury in stroke is determined by
site of stenosis or occlusion, cardiac function, collateral blood flow
the frontal lobe controls
motor output, short term memory
the parietal lobe controls
sensory input
the occipital lobe controls
visual processing
the temporal lobe controls
auditory processing, language recognition
the cerebellum controls
skeletal muscle contractions, balance
the brainstem controls
respiration, HR, BP
ischemic penumbra
the part of the brain sandwiched between brain regions committed to die and those that receive enough blood to communicate: has the capacity to be salvaged, has compromised blood flow (collateral)
major risk for cardioembolic sources of stroke
AFib, mitral stenosis, prosthetic mechanical valve, recent MI, left ventricular thrombus, atrial myxoma, ineffective endocarditis, dilated cardiomyopathies
minor/unknown risk for cardioembolic sources of stroke
mitral valve prolapse, mitral annular calcification, patent foramen ovale, atrial septal aneurysm, calcific aortic stenosis
clinical presentation and diagnosis of stroke
focal neurological deficit with abrupt onset of symptoms (in the absence of trauma) such as muscle numbness or weakness especially on one site of the body, trouble speaking, trouble seeing, and severe headache with no known cause
what is the gold standard for stroke severity rating
NIHSS: national institutes of health stroke scale
NIHSS score should be assessed within __ hours for all stroke patients
12
what can the total NIHSS score predict
outcome, or presence of large vessel occlusion
NIHSS score 0
no stroke
NIHSS score 1-4
minor stroke
NIHSS score 5-15
moderate stroke
NIHSS score 15-20
moderate to severe stroke
NIHSS score 21-42
severe stroke
get a CT scan within ____ of arrival
25 minutes
on the CT scan, an area of ischemia will look ___
dark
on the CT scan, an area of hemorrhage will look
white
treatment goals for stroke
restore normal cerebral blood flow as soon as possible, minimize neurologic damage, protect neurons by slowing the ischemic cascade
supportive care for stroke
IV fluids (NS, dextrose, plasmalyte, LR), blood glucose, acetaminophen. NOTHING BY MOUTH (NPO)
patient eligibility for fibrinolytics
> 18 years old, diagnosis of ischemic stroke, onset of symptoms <3 hours, no stroke or head trauma within 3 months, no major surgery within 14 days, no history of ICH, SBP <185, DBP< 110, no need for aggressive BP lowering to within goal, no known malignant intracranial neoplasm, no subarachnoid hemorrhage, no GI/urinary tract hemorrhage within 21 days, no arterial puncture within 7 days, no seizure at onset of stroke, INR <1.7 without anticoagulant, aPTT within normal range, platelets >100,000, blood glucose >50 mg/dl, no rapidly resolving symptoms, no active bleed, no known structural cerebral vascular lesion
additional exclusion criteria if symptom onset 3-4.5 hours
> 80 years old, warfarin regardless of INR, baseline NIHSS score >25, history of both stroke and diabetes
what does tPA stand for
tissue plasminogen factor
administer tPA to eligible patients within ____ hours after start of stroke symptoms
3-4.5
dosing for tpa
0.9 mg/kg: give 10% bolus over 1 minute, give the rest (90%) over 1 hour, max for any patient is 90 mg
are other thrombotic agents recommended at the time of tpa
NO
_______ is an option for MAJOR stroke if administered within 6 hours of symptom onset at an experienced stroke center
intra-arterial thrombolysis
how to monitor after giving tpa
neuro assessments every 15 minutes during infusion, every 30 minutes for 6 hours, every 60 minutes for 16 hours. d/c infusion if severe headache, acute hypertension, n/v. check BP every 15 minutes for 2 hours, every 30 minutes for 6 hours, and every 60 minutes for 16 hours.
avoid antiplatelets and anticoagulants for ____ hours after fibrinolytic
24-48
additional pharmacotherapy monitoring for tpa
resolving of stroke symptoms, signs and symptoms of intracranial hemorrhage, side effects of individual agents used as applicable
indications for antihypertensives in acute ischemic stroke
SBP> 180 &/or DBP >105 in patients given tpa; aortic dissection; acute MI; heart failure; acute renal failure; hypertensive encephalopathy
antihypertensive options for stroke
labetalol, nicardipine, nitroprusside
labetalol dosing
10-20 mg IV, may repeat or double dose every 10 minutes (max 300 mg)
nicardipine dosing
5 mg/hr IV infusion, may titrate by 2.5 mg/hr every 5 minutes (max 15 mg/hour)
nitroprusside dosing
0.5 mcg/kg/min IV infusion
aim for ___% reduction in BP
10-15%
algorithm for patients treated with thrombolytics
NS 75-100 mL/hr, NO heparin/warfarin/aspirin/clopidogrel/dipyridamole for 24 hours THEN start antithrombotic, brain CT or MRI after 24 hours of rtPA
algorithm for patients not treated with thrombolytics
NS 75-100 mL/hr, antiplatelet (aspirin) should be ordered within first 24 hours of hospital admission, heparin/warfarin are NOT recommended until after 24 hours in cardioembolic state and patient is stable. repeat brain CT or MRI may be ordered 24-48 hours after stroke
aspirin dose
initial dose of 325 mg recommended within 24-48 hours of stroke onset to decrease stroke recurrence risk and mortality
heparin for stroke?
therapeutic anticoagulation w/ IV/SQ UFH/LMWH is NOT recommended for acute ischemic stroke treatment. is recommended low dose SQ UFH/LMWH for DVT/PE prophylaxis
algorithm if patient is eligible for tPA and BP is >185/110
treat BP first before TPA, start ASA 24 hours after TPA
algorithm if patient is eligible for tPA and BP is <185/110
start tPA, start ASA 24 hours after TPA
algorithm if patient is not eligible for tPA
asa 325 mg daily & no anticoagulants within 24 hours, may consider after 24 hours
complications with stroke
seizure, cerebral hemorrhage, cerebral edema, hemiplegia, aphasia, depression, sensory deficits
hemiplegia
one sided muscle weakness/paralysis
secondary prevention of stroke if non-cardioembolic (i.e. not AFib)
asa monotherapy, or asa 25 mg + dipyridamole 200 mg (aggrenox) bid, or clopidogrel 75 mg qd
secondary prevention of stroke if cardioembolic (AFib)
DOAC, warfarin (target inr 2.5), ChA2DS2-VASc
statin therapy
intense, atorvastatin 80 mg qd, regardless of cholesterol profile, is recommended for patients with TIA and ischemic stroke
what to do if intracerebral hemorrhage
no standard treatment, treat hypertension, reverse anticoagulation, poor prognosis, mannitol to maintain serum osmolarity and arterial pressure
warfarin reversal
FFP or PCCs (KCentra, Profilnine, FEIBA), vitamin K IV, recombinant activated factor VIIa (novoseven)
dabigatran reversal
praxbind (idaracizumab)
andfactor Xa inhibitor reversal
andexanet
