Transient Ischemic AttackTransient Ischemic Attack

Courtney Wilson, BSN, RN-CCourtney Wilson, BSN, RN-CMSN 621 - 2012MSN 621 - 2012

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AT THE COMPLETION OF THIS AT THE COMPLETION OF THIS TUTORIAL THE LEARNER WILL: TUTORIAL THE LEARNER WILL:

1. Identify the pathophysiology of a transient 1. Identify the pathophysiology of a transient

ischemic attack (TIA).ischemic attack (TIA).

2. Identify the clinical implications of a TIA.2. Identify the clinical implications of a TIA.

3. Identify TIA diagnostic tools.3. Identify TIA diagnostic tools.

4. Identify medical treatments for a TIA.4. Identify medical treatments for a TIA.

5. Identify the risk factors for a TIA.5. Identify the risk factors for a TIA.

6. Identify measures to prevent a TIA. 6. Identify measures to prevent a TIA.

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WHAT TO EXPECTWHAT TO EXPECT You will be presented material about TIAs and You will be presented material about TIAs and

given an interactive quiz at the end of each given an interactive quiz at the end of each section. Rationales for answers will be provided.section. Rationales for answers will be provided.

At the end of the tutorial a case study is At the end of the tutorial a case study is presented, allowing you to apply your knowledge presented, allowing you to apply your knowledge of TIAs to clinical practice.of TIAs to clinical practice.

““HOVER AND DISCOVER.” When you see words HOVER AND DISCOVER.” When you see words underlined in underlined in TEALTEAL, hover over them to receive , hover over them to receive additional information on the subject.additional information on the subject.

Please utilize the provided hyperlinks. Double Please utilize the provided hyperlinks. Double click on the underlined websites inclick on the underlined websites in TEAL TEAL to to access them directly.access them directly.

ENJOY AND HAVE FUN!ENJOY AND HAVE FUN!

A TIA ISA TIA IS A transient cerebral blood flow disruption which A transient cerebral blood flow disruption which

affects a focal portion of the brain, causing affects a focal portion of the brain, causing temporary ischemia without acute infarction.temporary ischemia without acute infarction.

A transient ischemia attack of the brain causing A transient ischemia attack of the brain causing neurological deficits which last for less than 24 neurological deficits which last for less than 24 hours; most often less than 1 to 2 hours. hours; most often less than 1 to 2 hours. TIA TIA symptoms are RAPID in onset!symptoms are RAPID in onset!

Caused by atherosclerotic disease of the cerebral Caused by atherosclerotic disease of the cerebral vessels and emboli that temporarily disturb blood vessels and emboli that temporarily disturb blood flow to a portion of the brain. This blockage flow to a portion of the brain. This blockage resolves on its own before permanent neurological resolves on its own before permanent neurological damage occurs.damage occurs. Clot formation may result from… Clot formation may result from… (Porth & Matfin, (Porth & Matfin,

2009)2009)

Hypercoagulability Vessel spasm Disturbed blood flow

A TIA ISA TIA IS Known as a “warning” or “mini” stroke. Known as a “warning” or “mini” stroke.

4 to 8% of patients are at risk of having a 4 to 8% of patients are at risk of having a stroke within 1 month of having a TIA! stroke within 1 month of having a TIA! (American (American Stroke Association, 2012)Stroke Association, 2012)

Also described as a Also described as a “zone of penumbra “zone of penumbra without central infarction.”without central infarction.” (Porth, 2009) (Porth, 2009)

Penumbra Penumbra means “halo.”means “halo.” During the stroke process there is usually a central During the stroke process there is usually a central

core or “zone” of ischemic cells. This area is core or “zone” of ischemic cells. This area is surrounded by an ischemic band or area of poorly surrounded by an ischemic band or area of poorly perfused cells called the perfused cells called the PENUMBRAPENUMBRA. There is NO . There is NO cell infarction that occurs during a TIA!cell infarction that occurs during a TIA!

WARNING STROKE

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Clot or plaque in the cerebral vessel

Focal ischemic area in the brain

“Zone” of ischemic cells

Penumbra surrounds this area

A TIA ISA TIA IS Brain cells of the Brain cells of the PenumbraPenumbra receive collateral blood receive collateral blood

supply from nearby vessels. The “support” vessels supply from nearby vessels. The “support” vessels anastomose with branches of the occluded vessel to anastomose with branches of the occluded vessel to provide supplemental perfusion.provide supplemental perfusion.

The ischemic area of the brain experiences The ischemic area of the brain experiences temporary ‘electrical failure’ during the TIA, causing temporary ‘electrical failure’ during the TIA, causing neurological deficits. Because perfusion is quickly neurological deficits. Because perfusion is quickly restored, the structure of the brain cell is maintained restored, the structure of the brain cell is maintained and permanent sequelle do not occur.and permanent sequelle do not occur.

Stroke Center (n.d.) Used by permission.

Note the dark grey area surrounding the light grey ischemic cells. This is the PENUMBRA.

Ischemic area

A TIA ISA TIA IS

A type of “brain attack” where the A type of “brain attack” where the penumbra cells SURVIVE! penumbra cells SURVIVE!

Cerebral vessel survival depends on Cerebral vessel survival depends on successful successful TIMELYTIMELY return of adequate return of adequate circulation to the ischemic area.circulation to the ischemic area.

Remember:Remember:TIA = ZONE OF PENUMBRA TIA = ZONE OF PENUMBRA WITHOUT CENTRAL INFARCTION.WITHOUT CENTRAL INFARCTION.

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REVIEW QUESTIONREVIEW QUESTION

A TIA is a ___________blockage (clot) A TIA is a ___________blockage (clot) that occurs in a focal part of the brain.that occurs in a focal part of the brain.

permanent

FALSE TIA symptoms resolve once the blood flow

returns to thecerebral artery that is

affected.

partial

FALSEThe blockage is

complete, but does not remain long enough to cause permanent brain

damage.

transient

TRUETIA symptoms “come and

go”. They resolve once blood flow is restored to

the area of the brain affected.

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REVIEW QUESTIONREVIEW QUESTIONFocal ischemic cerebral neurological Focal ischemic cerebral neurological

deficits deficits (TIAs) usually last less than ______.(TIAs) usually last less than ______.

24 – 48 hrs

FALSENot quite, this is a little too long. Symptoms last

less than 24 hrs.

1 week

FALSEThis is too long for TIA

symptoms. Stroke symptoms may last this

long.

1 – 2hrs

TRUETIA symptoms last less than 24hrs, usually less

than 1 to 2 hrs.

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CLINICAL IMPLICATIONS OF A CLINICAL IMPLICATIONS OF A TIATIA Symptoms of a TIA are EXACTLY the same as for a Symptoms of a TIA are EXACTLY the same as for a STROKE!STROKE!

Is considered a critical situation!Is considered a critical situation!

The specific manifestations of a TIA are determined The specific manifestations of a TIA are determined by…by… The affected cerebral artery.The affected cerebral artery. The area of brain tissue supplied by that vessel.The area of brain tissue supplied by that vessel. The adequacy of the collateral circulation. (Porth, 2009)The adequacy of the collateral circulation. (Porth, 2009)

=TIA SYMPTOMS = AN EMERGENCY!

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CLINICALCLINICAL IMPLICATIONSIMPLICATIONS OF A OF A TIATIASymptoms of a TIA are always sudden in Symptoms of a TIA are always sudden in

onset,onset,focal and usually unilateral (one-sided).focal and usually unilateral (one-sided). (Porth, (Porth,

2009)2009)

TIA symptomsTIA symptoms (Porth, 2009)(Porth, 2009) Weakness to the face, arm, leg. Weakness to the face, arm, leg. (Most common)(Most common)

Unilateral Numbness. Unilateral Numbness. Parasthesia

Confusion, trouble speaking or understanding.Confusion, trouble speaking or understanding. Aphasia Dysarthria

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CLINICAL IMPLICATIONS OF A CLINICAL IMPLICATIONS OF A TIATIA

TIA Symptoms… TIA Symptoms… (Porth, 2009)(Porth, 2009) Trouble seeing in one or both eyes. Trouble seeing in one or both eyes.

Amaurosis fugax Hemianopia

Trouble walking, dizziness, loss of balance or Trouble walking, dizziness, loss of balance or coordination.coordination.

Ataxia

Severe headache with no known cause.Severe headache with no known cause. Cephalgia

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REVIEW QUESTIONREVIEW QUESTION

The most common manifestation of a TIAThe most common manifestation of a TIAis______. This symptoms usually presents is______. This symptoms usually presents unilaterally.unilaterally.

Dysarthria

FALSESorry, this is not the most common TIA symptom. It

means to have slurred

speech.

Weakness

TRUEUnilateral weakness to

the face & arm, and sometimes leg is the

most common TIA symptom.

Hemanopia

FALSEGood try, but this is not

the most common symptom of a TIA. It

means to have lost ½ of

your visual field.

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REVIEW QUESTIONREVIEW QUESTION

The manifestations of a TIA are _________ The manifestations of a TIA are _________ in onset and usually ___________ in in onset and usually ___________ in presentation.presentation.

Progressive/Bilateral

FALSESorry, TIA symptoms are rapid in onset and usually affect only one side of the

body. This symptom would require additional

testing.

Sudden/ Unilateral

TRUEThis is correct! TIA

symptoms due occur suddenly and usually affect one side if the

body.

Slow/generalized

FALSENot quite, remember that

TIA symptoms occur rapidly and are unilateral

in nature.

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DIAGNOSING A TIADIAGNOSING A TIA The diagnostic evaluation should aim to…The diagnostic evaluation should aim to…

Determine the presence of hemorrhage or ischemiaDetermine the presence of hemorrhage or ischemia

Identify the stroke or TIA mechanism (cause)Identify the stroke or TIA mechanism (cause)

Characterize the severity of the clinical deficitsCharacterize the severity of the clinical deficits

Unmask the presence of risk factors. Unmask the presence of risk factors. (Porth, 2009)(Porth, 2009)

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DIAGNOSING A TIADIAGNOSING A TIA

1. Complete History1. Complete History Documentation of previous TIAs or strokes.Documentation of previous TIAs or strokes. The time of onset, pattern and rapidity of The time of onset, pattern and rapidity of

system progression.system progression. Specific focal systems. (Porth, 2009). (Porth, 2009)

2. Physical and neurological exam2. Physical and neurological exam.. National Institute of Health neurological exam National Institute of Health neurological exam NIH Stroke Scale (NIH)(NIH)

(Double click above to check it out!)(Double click above to check it out!)

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http://www.ninds.nih.gov/doctors/NIH_Stroke_Scale.pdf

DIAGNOSING A TIADIAGNOSING A TIA3. 3. Imaging StudiesImaging Studies..

BRAIN IMAGINGBRAIN IMAGING – document the brain – document the brain infarction.infarction.

CT Scan of the brain – Preferred imaging in an – Preferred imaging in an emergent/acute setting to rapidly rule out a cerebral emergent/acute setting to rapidly rule out a cerebral hemorrhage diagnosis.hemorrhage diagnosis.

CAUTION: THE TIA PATIENT WILL HAVE A CAUTION: THE TIA PATIENT WILL HAVE A NEGATIVE CT SCAN OF THE HEAD! NEGATIVE CT SCAN OF THE HEAD!

Magnetic Resonance Imaging (MRI) of the brain ––Preferred imaging for ischemic lesions of the brain.Preferred imaging for ischemic lesions of the brain.

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DIAGNOSING A TIADIAGNOSING A TIA VASCULAR IMAGINGVASCULAR IMAGING – identifies the anatomy – identifies the anatomy

and pathologic processes of the related blood and pathologic processes of the related blood vessels.vessels. (Porth 2009)(Porth 2009)

CT Angiography (CTA):

Magnetic Resonance Angiography (MRA):

Catheter based “conventional” angiography :

Ultrasonography : Duplex Ultrasonography: assessment of the Duplex Ultrasonography: assessment of the

carotid bifurcation.carotid bifurcation. Transcranial Doppler: assessment of the flow Transcranial Doppler: assessment of the flow

velocities in the cerebral circulation. velocities in the cerebral circulation. Microsoft clip art

CASE STUDYCASE STUDY

Patient:Patient: 68 yr old African American male, Mr. G, presents to the ED 68 yr old African American male, Mr. G, presents to the ED with reports of numbness and tingling to his right face, right arm, with reports of numbness and tingling to his right face, right arm, and slight difficulty with word choice for the past 35 minutes. No and slight difficulty with word choice for the past 35 minutes. No facial asymmetry noted. He also reports a moderate to severe facial asymmetry noted. He also reports a moderate to severe headache since yesterday. Patient ran out of his BP meds 1 week ago headache since yesterday. Patient ran out of his BP meds 1 week ago and states he forgot to refill them. He tells the RN that his BP was and states he forgot to refill them. He tells the RN that his BP was “normal” when he checked it a month ago. “normal” when he checked it a month ago.

MEDS:MEDS: Lisinopril 40mg/day & Metformin 1000mg/BID. Patient states he Lisinopril 40mg/day & Metformin 1000mg/BID. Patient states he

isn’t the best at taking his medications daily.isn’t the best at taking his medications daily.

VITALS:VITALS: 178/98, 96, 18, 98.6, Pox 96% at room air. 178/98, 96, 18, 98.6, Pox 96% at room air.

Glucose /capillary : 120mg/dL NIH score = 2Glucose /capillary : 120mg/dL NIH score = 2

PAST MEDICAL HISTORY:PAST MEDICAL HISTORY: - NKDA - Diabetes Mellitus/Type II - NKDA - Diabetes Mellitus/Type II - HTN, Hyperlipidemia, recent cholesterol of 190.- HTN, Hyperlipidemia, recent cholesterol of 190.

- No surgeries or previous hospitalizations.- No surgeries or previous hospitalizations.

????

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????

REVIEW QUESTIONREVIEW QUESTIONWhat is the What is the INITIALINITIAL diagnostic imaging test that diagnostic imaging test that

would be would be completed when Mr. G arrives to the ER with his completed when Mr. G arrives to the ER with his

symptoms symptoms to provide a differential diagnosis?to provide a differential diagnosis?

MRI of the brain

FALSEMRI is a superior test for

diagnosing ischemic lesions in the brain, but it is not a fast test. The CT

scan of the head will quickly provide a

differential diagnosis (stroke vs TIA). Time is

brain function!

CT of the head without contrast

TRUEThe CT of the head will

quickly differentiate between a stroke and a TIA. This will help direct

the patient’s plan of care.

Duplex ultrasonography

FALSEThis is a fast noninvasive

test that will provide information to the

patency of the carotid arteries and the blood

flow to the brain. This will assist in possible surgical

options if a large blockage presents. This is

not the initial imaging that would be completed.

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TIA TREATMENTTIA TREATMENT

TIA treatment is focused on preventing recurrent TIAs, TIA treatment is focused on preventing recurrent TIAs, strokes and medical complications. strokes and medical complications.

““The risk of stroke is highest in the first week after The risk of stroke is highest in the first week after stroke or TIA.”stroke or TIA.” (Porth, 2009, p. 1324)(Porth, 2009, p. 1324)

Early implementation of antiplatelet agents in most Early implementation of antiplatelet agents in most cases is the standard of care.cases is the standard of care.

Current treatment options for TIA include Current treatment options for TIA include (Porth, 2009)(Porth, 2009)

ASPIRIN - first line of medical treatment.- first line of medical treatment. TICLOPIDINE CLOPIDOGREL CAROTID ENDARDECTOMY

TIA TREATMENTTIA TREATMENT According to the American Heart Association’s According to the American Heart Association’s

journal journal Stroke.Stroke. DepressionDepression is more prevalent among stroke and is more prevalent among stroke and

transient ischemic attack survivors than in the general transient ischemic attack survivors than in the general population. It is underdiagnosed and undertreated.population. It is underdiagnosed and undertreated.

Researchers, analyzing 1,450 adults with ischemic stroke Researchers, analyzing 1,450 adults with ischemic stroke (blockage of a blood vessel in the brain) and 397 with TIA, (blockage of a blood vessel in the brain) and 397 with TIA, found:found:

Three months after hospitalization, depression affected 17.9 Three months after hospitalization, depression affected 17.9 percent of stroke patients and 14.4 percent of TIA patients.percent of stroke patients and 14.4 percent of TIA patients.

At 12 months, depression affected 16.4 percent of stroke At 12 months, depression affected 16.4 percent of stroke patients and 12.8 percent of TIA patients.patients and 12.8 percent of TIA patients.

Nearly 70 percent of stroke and TIA patients with persistent Nearly 70 percent of stroke and TIA patients with persistent depression still weren’t treated with antidepressant therapy depression still weren’t treated with antidepressant therapy at either the 3 or 12 month intervals.at either the 3 or 12 month intervals.

OUTCOME:OUTCOME: It is important for providers to screen for It is important for providers to screen for depression on follow-up after both stroke and TIA. depression on follow-up after both stroke and TIA.

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http://newsroom.heart.org/pr/aha/depression-has-big-impact-on-stroke-

231095.aspx

REVIEW QUESTIONREVIEW QUESTION Mr. G’s CT of his head was NEGATIVE. It has now been 35 Mr. G’s CT of his head was NEGATIVE. It has now been 35

minutes since he has arrived to the ED. His stroke minutes since he has arrived to the ED. His stroke symptoms have resolved. His BP is lower at 145/76, rate 78 symptoms have resolved. His BP is lower at 145/76, rate 78 after taking his Lisinopril 40mg which he is prescribed daily. after taking his Lisinopril 40mg which he is prescribed daily. DIFFERENTIAL DIAGNOSIS = TIADIFFERENTIAL DIAGNOSIS = TIA. .

What other medication will they most likely add to his daily What other medication will they most likely add to his daily medication regime? He reports no adverse reactions to any medication regime? He reports no adverse reactions to any medications.medications.

Clopidogrel

FALSETrue, this medication can be used to treat recurrent TIAs, but this is not a first

line medication for TIA prevention.

Aspirin

TRUEOne adult Aspirin/day is the most common first

line medication for preventing future TIAs.

Ticlopidine

FALSEThis medication is a first

line drug for TIA prevention, but it is

usually reserved for those who are unable to tolerate aspirin.

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TIA RISK FACTORSTIA RISK FACTORS

UnmodifiableUnmodifiable factorsfactors

Age, Sex, Race, HeredityAge, Sex, Race, Heredity The incidence of stroke INCREASES with age.The incidence of stroke INCREASES with age.

Stroke incident is greater among men than women’s at Stroke incident is greater among men than women’s at younger ages, but not at older ages.younger ages, but not at older ages.

African Americans have almost 2x the risk of initial African Americans have almost 2x the risk of initial stroke than caucasians.stroke than caucasians.

Familial history of strokes/ TIAs.Familial history of strokes/ TIAs.

(Porth, 2009)

TIA RISK FACTORSTIA RISK FACTORSModifiable FactorsModifiable Factors

Hypertension –powerful determinant of stroke risk! –powerful determinant of stroke risk! HyperlipidemiaHyperlipidemia SmokingSmoking DiabetesDiabetes Heart Disease (Atrial Fibrillation, Wall motion Heart Disease (Atrial Fibrillation, Wall motion

defects)defects) Carotid diseaseCarotid disease Coagulation disordersCoagulation disorders Obesity/InactivityObesity/Inactivity Heavy alcohol useHeavy alcohol use Cocaine use Cocaine use

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(Porth, 2009)

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REVIEW QUESTIONREVIEW QUESTION

What is Mr. G’s most predominant What is Mr. G’s most predominant modifiable stroke/TIA risk factor?modifiable stroke/TIA risk factor?

Hyperlipidemia

FALSETrue, this a modifiable

stroke risk factor, but not the most predominant for

Mr. G.

African American

FALSEAfrican Americans do

have higher incidence of stroke vs. Caucasians,

but this is not a modifiable risk factor.

Hypertension

TRUEHTN is a powerful

determinant of stroke/TIA risk. Mr. G’s BP is

elevated and he hasn’t taken his HTN meds for 1 week. You must discuss with him the importance of medication compliance in preventing future TIAs

or strokes!

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TIA PREVENTIONTIA PREVENTION

Treatment Treatment and and managementmanagement of modifiable risk factors offers of modifiable risk factors offers the best opportunity to prevent cerebral ischemic events.the best opportunity to prevent cerebral ischemic events. (Porth (Porth 2009)2009)

Primary preventionPrimary prevention of stroke byof stroke by early detectionearly detection. IMMEDIATE . IMMEDIATE TREATMENT IS NEEDED AT THE FIRST SIGN OF STROKE! TREATMENT IS NEEDED AT THE FIRST SIGN OF STROKE!

Be proactive with your patients regarding managing their modifiable risk Be proactive with your patients regarding managing their modifiable risk factors, don’t wait until an ischemic event occurs!factors, don’t wait until an ischemic event occurs!

Promote the importance of…Promote the importance of… Medication compliance. Medication compliance. Daily exercise, goal of 30 minutes/day.Daily exercise, goal of 30 minutes/day. Smoking cessation.Smoking cessation. Refraining from illegal drug or ETOH use.Refraining from illegal drug or ETOH use. Chronic disease managementChronic disease management

- (HTN/CAD/DM/A-fib)- (HTN/CAD/DM/A-fib)

Preventionis key!

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REVIEW QUESTIONREVIEW QUESTION What will be the What will be the most effectivemost effective PREVENTATIVE PREVENTATIVE

measure Mr. G can do to prevent future TIAs or measure Mr. G can do to prevent future TIAs or strokes.strokes.

Exercise

FALSETrue, this is a great

preventative measure, but not the most effective

for Mr. G at this time.

Take his BP everyday

FALSEAlthough this action will

allow for better HTN monitoring,

it unfortunately will not prevent future TIAs/

strokes.

Medication compliance

TRUEMr. G’s BP was elevated and he hadn’t taken his

HTN meds for 1 week. He may have prevented his TIA had he been taking

his meds.

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Let’s review what you’ve Let’s review what you’ve

learned in this tutoriallearned in this tutorial.. The pathophysiology of a TIA.The pathophysiology of a TIA. The clinical implications of a TIA.The clinical implications of a TIA. How a TIA is diagnosed.How a TIA is diagnosed. Common treatments for a TIA.Common treatments for a TIA. The risk factors of a TIA. The risk factors of a TIA. TIA prevention.TIA prevention.

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LITERATURE CITEDLITERATURE CITEDAmerican Stroke Association (January/February 2009) Why Rush? American Stroke Association (January/February 2009) Why Rush? Stroke Connection.Stroke Connection.Retrieved March 15, 2012 from Retrieved March 15, 2012 from http://www.strokeassociation.org/STROKEORG/AboutStroke/TypesofStroke/TIA/http://www.strokeassociation.org/STROKEORG/AboutStroke/TypesofStroke/TIA/

TransientTransient-Ischemic-Attack_UCM_310942_Article.jsp-Ischemic-Attack_UCM_310942_Article.jsp

American Stroke Association (March 2012) Depression has big impact on stroke, TIA American Stroke Association (March 2012) Depression has big impact on stroke, TIA Survivors. Survivors. StrokeStroke. Retrieved March 15, 2012 from. Retrieved March 15, 2012 fromhttp://newsroom.heart.org/pr/aha/depression-has-big-impact-on-stroke-231095.aspxhttp://newsroom.heart.org/pr/aha/depression-has-big-impact-on-stroke-231095.aspx

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National Institute of Health (October 2003) National Institute of Health Stroke Scale for National Institute of Health (October 2003) National Institute of Health Stroke Scale for doctors. Retrieved March 1, 2012 from doctors. Retrieved March 1, 2012 from http://www.ninds.nih.gov/doctors/NIH_Stroke_Scale.pdfhttp://www.ninds.nih.gov/doctors/NIH_Stroke_Scale.pdf

Porth, C. M., & Matfin, G. (2009). Porth, C. M., & Matfin, G. (2009). Pathophysiology Concepts of Altered Health States Pathophysiology Concepts of Altered Health States (8(8thth

ed.). Philadelphia, PA: Lippincott Williams& Wilkins.ed.). Philadelphia, PA: Lippincott Williams& Wilkins.

Stroke Center (n.d.). The Ischemic Penumbra. Permission received to use image. Stroke Center (n.d.). The Ischemic Penumbra. Permission received to use image. Retrieved March 15, 2012. Retrieved March 15, 2012. http://www.strokecenter.org/professionals/brain-anatomy/cellular-injury-during-http://www.strokecenter.org/professionals/brain-anatomy/cellular-injury-during-ischemia/the-ischemic-penumbra/ischemia/the-ischemic-penumbra/