Stroke and TIA Flashcards
In stroke, secondary injury results from what?
Edema, mass effect
TIA definition
Transient episode of neurological dysfunction by focal brain, spinal cord, or retinal ischemia without acute infarction
How long does TIA usually last?
1-2 hours (usually less than 24)
What percent of TIA will have ischemic stroke and when?
10% in 90 days
get early re-perfusion?
Quick use of thrombolytics and neuroprotective agents
Will perfusion return to baseline in hemorrhagic stroke?
No
Describe arteries of brain
Worst HA of life is what?
SAH
What is more common type of hemorrhagic stroke and what are causes?
ICH-
•Elderly, Hx of Stroke; also ETOH and tobacco use
•Anticoagulation, cocaine, vascular malformation, amyloidosis
What is most important when diagnosing stroke?
Timing
On fundoscopic exam, what may papilledema indicate?
Mass lesion, HTN crisis
On fundoscopic exam, what may preretinal hemorrhage indicate?
SAH
When is NIHSS stroke scale used?
Baseline and serial exams (post-CT, 2 hours, 24 hours, 7-10 days, 3 mo)
What percent of TIA becomes stroke within 2 days of ED presentation?
50%
Findings of unilateral ACA infarction:
•Contralateral sensory & motor sx’s in LE’s
•Sparing of hands & face
•Left sided lesions = akinetic mutism (unmoving / unspeaking)
•Transcortical Motor Aphasia (TMA) = comprehension with non-fluent speech
•Right sided lesions = confusion & motor hemi-neglect
–Bilateral = combination of mutism & incontinence; worsened outcomes
What is most common infarction?
MCA
MCA infarction findings:
- Hemiparesis, facial plegia, contralateral sensory loss
- Face & UE > LE
- Dominant hemisphere = aphasia (receptive, expressive OR both)
- Nondominant hemisphere = inattention, neglect, extinction, dysarthria w/o aphasia, constructional apraxia (difficulty drawing complex 2-D or 3-D objects)
- Homonymous hemianopsia & gaze preference in either
How does PCA infarction classically present?
Visual field defects
What is most common presenting complaint with PCA?
Unilateral HA
Other findings of PCA:
–Light-touch & pinprick deficits
–Alexia w/o agraphia: can’t read but writes
–Cannot name colors & recent memory loss
–Unilateral CN III palsy & hemiballism
–Motor minimally affected: prevents realization that one has had a stroke
Most common symptom of vertebrobasilar artery:
Vertigo
Other findings of vertebroasilar:
- HA, nausea, visual disturbances & oculomotor palsies
- Ataxia, sensory disturbances, limb weakness, oropharyngeal dysfunction
Hallmark presentation of posterior circulation stroke:
•Crossed neurologic deficits
–Ipsilateral CN deficits w/ contralateral motor weakness
•Basilar Artery Occlusion
–Severe quadriplegia, coma, locked-in syndrome
Cerebellar Infarct findings
–Vertigo, gait disturbance, limb ataxia, HA, dysarthria, nausea, vomiting, CN abnormalities
–Mental Status variable & may deteriorate rapidly
–MRI/MRA better than CT
–Prompt Neurosurgical consultation a must
–Obstructing hydrocephalus = BAD
Lacunar Infarction findings:
–Pure motor or sensory deficits
–Clumsy hands & dysarthria
–Unilateral leg paresis & ataxia
–Small penetrating artery involvement
–Chronic HTN and age related
–Variable presentation
•May be sub-clinical
–More favorable prognosis
What is commonl in Hx of cervical artery dissection?
Neck trauma, often trivial
Internal Carotid Artery Dissection findings:
•Unilateral head pain (1st symptom), face pain, neck pain, partial Horner’s syndrome
Vertebral artery dissection findings:
- Posterior neck pain & headache (posterior-occipital)
- Can be unilateral or bilateral HA; typically occipital
- Unilateral facial paresthesia, dizziness, vertigo, N/V, diplopia, ataxia, limb weakness, numbness, dysarthria, hearing loss
What is a PE finding for cerebellar infarct?
Cannot look toward side of bleed
What is SAH associated with?
Valsalva
Within how long should brain imaging occur upon arrival?
Within 25 min
Treatment decision of stroke should occur within how long of arrival?
60 min
Treatment approach for stroke
•“Safety Net” – don’t forget the D-stick
•Very brief history
•ABCs
•Diagnostic studies
–STAT EKG
–PCXR
–Your labs
–Non-contrast head CT!!
Who reads CT for stroke?
Most expert interpreter
What is therapeutic range of INR?
2-3
What is ancillary testing for Stroke/TIA?
•CBC-look at platelets
•Chemistry
•ECG & Cardiac Enzymes
•Coags-If patient is on blood thinner, what should INR be?
–Therapeutic Range for INR is between 2.0-3.0
•Type and Screen
What should be addressed when ischemic stroke?
•Dehydration: give IV crystalloids
•Hypoxia: maintain O2 Sats > 92%
•Hyperpyrexia: search for & treat the cause of the fever (sepsis, PNA, UTI, meningitis)
•Hypertension
Hyperglycemia
What is go-to drug for HTN?
labetalol
What is HTN requirement for thrombolytics in ischemic stroke?
Must be 185/110 within 2 doses of labetalol. If takes more than 2 doses then no longer candidate for thrombolytics
What is the only acceptable CCB for ischemic stroke?
Nicardipine
What may worsen outcome of ischemic stroke?
Vasodilators
What thrombolytic is used in ischemic stroke?
Recombinant tissue-type plasminogen activator 0.9mg/kg, max dose of 90mg; 10% given as a bolus, 90% infused over 60 minutes
What must you do prior to pushing rTPA?
Consult but don’t delay
rTPA use requirements:
–Assessment
•NIHSS score (4-22)**[may be lower if posterior stroke suspected]
–Dose
•Total Dose 0.9mg/kg max dose of 90mg; 10% bolus, remainder over 60 minutes
–Reassess
•Neuro & BP checks Q15min x 2 hrs = ICU Admission
Post monitoring for rTPA:
–No ASA or heparin for 24 hours
–BP and Neuro exam q 15 minutes for 2hrs post administration
–SBP >180 or DBP>105 (2 consecutive)
•IV Labetalol 10 mg q 10-20 min to 300mg
•Nitroprusside infusion (0.5-1.0 mcg/kg) if no improvement with Labetalol
–If suspected post-rtPA bleed: CT, CBC, coags, fibrinogen, T & C; urgent Neurosurgery, Neurology, & Hematology consult
Antiplatelet therapy for TIA:
•Aspirin alone: start within 24 to 48 hours of TIA
–significantly reduces 4 week to 6 month mortality
•Dipyridamole & ASA
•Clopidogrel (Plavix)
