Neuro E2- Strokes & TIAs

What is very important to ask a patient that you suspect is having a stroke?

last time they were normal without signs of stroke

What is the death of brain tissue as a result of impaired perfusion?

cerebral infarction

What is a potentially reversible injury to brain tissue resulting from impaired perfusion?

cerebral ischemia

What is a brief episode of neuro dysfunction caused by focal brain/retinal ischemia with symptoms usually lasting less than 1 hour (completely resolved in 24 hrs)?

Transient ischemic attack (TIA)

What do TIAs indicate?

impending stroke

What is the syndrome of acute neurological deficits resulting form cerebral infarction due to a sudden focal interruption of cerebral blood flow?

stroke / CVA

What type of stroke?

• death of CNS tissue due to infarction that results from disruption of blood supply

• MC

ischemic

What type of stroke?

• rupture of abnormal blood vessel that results in local disrupted tissue structure and toxic effects of blood products that leads to cell death

hemorrhagic

What is the most common type of stroke?

ischemic thrombotic

What is the most common disabling neurological disorder and 5th MCC of death in the US?

stroke

HTN leads to thickening of vessel wall resulting in ______

lacunar infarct

What is the cause of most deaths that occur w/in 1 week after a massive cerebral infarction?

cerebral edema (reaches maximum 5 days after onset)

What is the main risk factor for all types of strokes?

arterial HTN

What are risk factors for strokes?

older age, smoking, DM, cardiac dz, A fib, preceding TIAs, arterial HTN

What is transient global amnesia?

memory disturbance w/o other neurons deficits

What is the most common metabolic disorder that can mimic a stroke?

hypoglycemia

What should you always get with a confused patient?

glucose levels

How does a migraine present differently than a stroke?

more gradual onset & slower development

What type of stroke presents with an abrupt onset followed by rapid improvement?

embolus

What type of stroke can present with an abrupt onset with progression to maximal deficit over mins-hrs, onset during sleep or a stepwise progression; & with gradual improvement over a day-few wks?

thrombus

What type of stroke has an onset associated with severe HA or alterations in consciousness with a rapid deterioration over a period of a few hours?

intracerebral bleed

An ischemic stroke of anterior circulation would involve what arteries?

carotids, anterior & middle cerebral arteries

An ischemic stroke of posterior circulation would involve what arteries?

vertebrobasilar & posterior cerebral arteries

If the dominant hemisphere is affected in carotid artery occlusion, what will the patient present with?

language deficits - slurred speech & aphasia

If the non dominant hemisphere is affected in carotid artery occlusion, what will the patient present with?

neglect & confusion

What is amaurosis fugax?

I/L monocular vision loss - feels as if a “shade” has come down over 1 eye

What syndrome are the following characteristics associated with?

• amaurosis fugax

• cortical function loss (depending on hemisphere)

  • **eyes deviate toward infarcted hemisphere

• episodic C/L paresis & paresthesia

• slurred speech & transient aphasia

• I/L vascular type HA

• carotid bruit

• microemboli/hemorrhage/exudate in I/L retina

Carotid artery syndrome

What may cause a stroke in the internal carotid territory?

atherosclerotic plaques at bifurcation causing embolization or complete occlusion

What may cause a stroke in the anterior cerebral artery territory?

emboli or SAH

What stroke is associated with the following symptoms?

• C/L paralysis & sensory loss of leg > arm

• C/L grasp reflex

• sucking reflex

• apraxic gait

• abulia

anterior cerebral artery occlusion

What is the inability to complete a motor task?

apraxia

What is abulia?

spontaneity lost & lack of concern that something is wrong

What stroke is associated with the following symptoms?

• C/L motor & sensory deficit

• homonymous hemianopsia

• cortical function loss (gaze deviates toward infarcted hemisphere)

• hemiparesis arm > leg

  • leg circumducted outward

• hemisensory loss

• hemianopsia

middle cerebral artery occlusion

If the dominant hemisphere is affected in middle cerebral artery occlusion, what symptoms will the patient have?

aphasia, agraphia, acalculia, alexia

If the non dominant hemisphere is affected in middle cerebral artery occlusion, what symptoms will the patient have?

hemispatial neglect (only groom 1 side), apraxia, confusion

The following sx are associated with what stroke?

• occipital lobe effects

  • hemianopsia- visual cortex, alexia w/o agraphia, memory deficit, unformed visual hallucination, thalamic syndrome (sensory loss, athetosis)

• brainstem affects

  • weber syndrome (I/L CN III palsy and C/L hemiplegia/paresis), paralysis of eye, ataxia

posterior cerebral artery occlusion

What stroke is associated with the following symptoms?

• binocular vision issues- blurry, diplopia, blindness

• vertigo, N, V, tinnitus

• sudden loss of postural tone of all 4 extremities (drop attacks) w/ no LOC

• slurred speech, ataxia, numbness around lips/face

• cranial neuropathy, eye movement abnormality

• paralysis, sensory loss

• coma

vertebrobasilar artery occlusion

What condition?

• stenosis/occlusion in subclavian artery proximal to vertebral artery → reversal of flow in vertebral artery stealing blood from posterior circulation

• blood is diverted away from brain to arm when UE is exercised

subclavian steal syndrome

What symptoms are associated with subclavian steal syndrome?

pre-syncope / syncope, neuro deficits, BP diff b/t arms, arm claudication

What is the treatment for subclavian steal syndrome?

endovascular stenting

small vessel disease is also known as _____

lacunar infarcts

What condition?

• not usually preceded by TIAs

• slowly evolving deficits

  • pure motor hemiplegia, dysarthria, ataxis hemiparesis, multi-infarct dementia

• step wise progression

• main risk factor = arterial HTN

small vessel disease

What happens with increased intracranial pressure?

dec respiratory drive → hypoventilation → inc CO2 → cerebral vasodilation → further elevation of ICP

What lab studies should be done for stroke patients?

CBC, ESR, CMP, fingerstick glucose, PT/PTT, & hyper coagulable workup for young pts

What is the most important diagnostic test for strokes?

STAT non contrast CT

Which stroke has the following appearance on a head CT?

• dark; may be normal w/in first 24 hours

ischemic stroke

What stroke has the following appearance on a head CT?

• bright/white & seen earlier

hemorrhagic stroke

What imaging study can detect acute infarcts sooner and is better at detecting strokes in the brainstem & cerebellum?

MRI

What test is the gold standard for AVM or SAH but has a 1% risk of stroke during the procedure?

conventional angiography

What is the only approved therapy for strokes?

tissue plasminogen activator (tPA)

How soon should tPA be administered for stroke patients?

w/in 3 hours of event (< 60 mins after arriving to ED)

What type of stroke cannot relieve tPA?

hemorrhagic

What should patients presenting with stroke onset who are NOT candidates for tPA be given?

ASA after exclusion of hemorrhage on brain CT

What is exclusion criteria for tPA?

• SBP > 185 mmHg or DBP > 110 mmHg

• sx of SAH

• head trauma / stroke in prior 3 mos

• active internal bleeding

• hx previous intracranial hemorrhage

• low plt count

• heparin w/in 48hrs & elevated aPTT

• etc

What is the relative exclusion criteria for tPA?

• only minor or quickly improving stroke sx

• pregnancy

• seizure at onset w/ postictal residual neuro impairments

• major surgery or serious trauma w/in prior 14 days

• recent GI or urinary tract hemorrhage in previous 21 days

• recent acute MI in previous 3 mos

BP should not be treated acutely in patients with ischemic strokes UNLESS _____

SBP > 220 mmHg and/or DBP over 120 mmHg

What is the BP management for ischemic stroke patients with elevated pressures meeting requirements for acute treatment?

labetalol IV; lower by 15% during first 24 hrs after onset of stroke

How should a stroke patient be managed after the acute event?

DVT/PE prophylaxis, PT/OT, speech therapy, swallow studies

How are TIAs distinguished from strokes?

complete resolution of focal neuro deficits w/in mins-hrs

When should you consider hospitalization for a patient with a TIA?

Pt w/ first TIA in past 24-48 hrs

sx that are worsening or last > 1 hr

known carotid artery stenosis, afib, or hypercoaguable state

What are treatment options for TIAs?

• consider tPA

• Antiplts

  • ASA 325 mg QD

  • Ticlopidine 250 mg BID (more effective but expensive)

  • clopidogrel 75 mg QD

• carotid endarterectomy

How do you determine risk of stroke for the next 7 days following a TIA?

ABCD rule

20% of all strokes are due to _______

Afib! (pt should be on anticoagulants)

What is more effective than ASA 81 mg in preventing strokes in Afib patients w/o significantly increasing the risk of bleeding complications?

warfarin w/ INR 2-3

What can be used to asses risk of stroke and drug selection?

CHADS2 score

• CHF - 1

• HTN - 1

• Age >75 - 1

• DM - 1

• prev Stroke or TIA - 2

What drug should a patient with a CHADS2 score of 0 be on?

ASA

What drug should a patient with a CHADS2 score of 1 be on?

ASA or warfarin

What drug should a patient with a CHADS2 score of ≥2 be on?

warfarin

What is the MC underlying cause of non-traumatic intracerebral hemorrhages?

HTN

How does chronic HTN cause intracerebral hemorrhages?

disrupts autoregulation of cerebral blood flow and promotes structural changes in walls of penetrating arteries

What are potential bleeding sites of intracerebral hemorrhages?

deep cerebral (putamen, thalamus), lobar (subcortical), pons, cerebellar

what are signs and symptoms of subarachnoid hemorrhage (SAH)?

“worst HA of my life”, LOC, HA, neck stiffness, nonfocal neuro exam

What kind of hemorrhagic stroke?

• usually due to ruptured cerebral arterial aneurysm or AVM → develops from weakness in vessel wall

• bleeding causes inc ICP (HA) and dec cerebral blood flow (LOC)

SAH

What condition?

• tangle of abnormal blood vessels connecting arteries & veins in brain

• MC in brain or spine; rare

• may cause HA or seizure; can be found incidentally

arteriovenous malformation (AVM)

What is the treatment for AVMs?

clipping

How does an intracerebral hemorrhage appear on an MRI?

bright center w/ dark periphery; changes as hematoma ages

What is the next step for a patient with a suspected SAH but negative non-contrast CT?

LP → xanthochromia (slightly tinged pink; develops ~4 hrs from hemorrhage)

What is the BP goal for ICH pts w/ SBP 150-220?

lower to 140

What is the BP goal for ICH patients w/ SBP > 220 mmHg?

lower to 140-160

aggressive reduction w/ IV labetolol, nicardipine, clevidipine, esmolol

What is the BP goal for SAH patient?

keep lower than 160

labetalol, nicardipine, lisinopril

(avoid nitroprusside & nitroglycerin)

How do you determine cerebral perfusion pressure (CPP)?

MAP - ICP

In what scenario would lowering BP not be ideal?

increased ICP

(lower BP increases risk of infarction; increased MAP may be the only way to perfuse)

How can you prevent elevated ICP in a hemorrhagic stroke patient?

elevate head of bed; consider sedation (barbiturate coma), mannitol, and hyperventilation (dec CO2 → vasodilation → lower pressure)

What should be done for ICH if risk for hydrocephalus?

external ventricular drainage (EVD)

What ICH patients are candidates for surgical treatment?

Grade 1: normal LOC & mild sx

Grade 3: confused & focal neuro deficits

What ICH patients are NOT candidates for surgical treatment?

Grade 5: coma & decerebrate posturing

What conditions carry high risk of mortality?

ICH & SAH