Stroke and TIA Overview

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Questions and Answers

What is the typical time frame for symptoms to progress in anterior circulation strokes?

Within the first 24 hours (correct)

Over one week

Within the first 12 hours

Up to 72 hours

Which symptom is least likely associated with a thrombosed ophthalmic artery?

Ipsilateral hemianopsia

Paralysis and hypesthesia of the lower limb (correct)

Amaurosis fugax

Homonymous hemianopsia

What is a key feature of hemorrhagic stroke mortality statistics?

30-day mortality rate can be up to 50% (correct)

Does not vary based on risk factors

Lower mortality rate compared to ischemic strokes

Always leads to complete recovery

What is the primary role of a Comprehensive Stroke Center (CSC)?

Perform surgical and endovascular interventions Signup and view all the answers

What imaging method has limited sensitivity for detecting posterior strokes?

CT scan Signup and view all the answers

What percentage of strokes are ischemic in origin?

87% Signup and view all the answers

Which symptom is NOT a risk factor for having a stroke after a TIA?

Nausea Signup and view all the answers

What is the most appropriate treatment for a high-risk TIA with an ABCD2 score of 4 or higher?

Aspirin and anticoagulants Signup and view all the answers

Which of the following best describes a transient ischemic attack (TIA)?

A temporary episode without acute infarction Signup and view all the answers

What does the mnemonic 'Blood Can Be Very Bad' help to remember while reading a CT head scan?

How to evaluate for intracranial hemorrhage Signup and view all the answers

What is often a clinical feature of anterior circulation strokes?

Bowel and bladder incontinence Signup and view all the answers

Which artery is specifically associated with amaurosis fugax when thrombosed?

Ophthalmic artery Signup and view all the answers

What should EMS ensure when transporting patients suspected of having a large vessel occlusion stroke?

Using the Triage Algorithm to direct them to a stroke center Signup and view all the answers

Which structure's dysfunction is most likely correlated with vertigo in strokes?

Cerebellum Signup and view all the answers

What is a common risk factor for hemorrhagic stroke?

Hypertension Signup and view all the answers

What is a key limitation of a CT scan in stroke diagnosis?

It has limited sensitivity for detecting posterior strokes Signup and view all the answers

How long can symptoms progress in cases of posterior circulation strokes?

Up to 3 days Signup and view all the answers

Which clinical sign is commonly associated with a dominant stroke?

Alexia Signup and view all the answers

What is the general mortality rate for ischemic strokes in a hospital setting?

5% to 10% Signup and view all the answers

What factor significantly increases the risk of having a stroke after experiencing a transient ischemic attack (TIA)?

Diabetes mellitus Signup and view all the answers

Which of the following represents the characteristics of a high-risk TIA?

ABCD2 score of 5 Signup and view all the answers

When assessing a CT head scan for blood, which structure would indicate a subarachnoid hemorrhage?

Cisterna magna Signup and view all the answers

What is the percentage of stroke survivors who are expected to recover completely?

10% Signup and view all the answers

Which of the following is NOT a type of hemorrhage associated with cerebral injury?

Intracranial thrombosis Signup and view all the answers

What does the NIH Stroke Scale (NIHSS) score measure in stroke patients?

Severity of neurological impairment Signup and view all the answers

Which type of stroke represents 87% of all stroke cases?

Ischemic stroke Signup and view all the answers

What is the primary purpose of the NIHSS scoring system?

To assess neuro-deficits and determine treatment options Signup and view all the answers

Which of the following subtle ischemic changes is NOT associated with increased risk of intracranial hemorrhage (ICH)?

Sulcus effacement Signup and view all the answers

What should be the target blood pressure for administering tPA?

Less than 185/110 Signup and view all the answers

Which factor is NOT a contraindication for tPA administration?

Age greater than 80 years Signup and view all the answers

During the management of a stroke patient, what is the target oxygen saturation level to maintain?

Above 95% Signup and view all the answers

What is the maximum dosage of alteplase for IV administration in eligible patients?

0.9 mg/kg Signup and view all the answers

What should be avoided to prevent complications in stroke patients?

Dehydration and fluid overload Signup and view all the answers

Which of the following is recommended for patients who are not eligible for tPA treatment?

Administration of aspirin within 24 to 48 hours Signup and view all the answers

What is the significance of the ENCHANTED trial results regarding low dose alteplase?

It found that low dose alteplase was non-inferior in terms of death and disability. Signup and view all the answers

What was one of the findings of the EXTEND-IA TNK trial compared to alteplase?

Tenecteplase was associated with a higher incidence of reperfusion. Signup and view all the answers

In which situation is administering IV alteplase contraindicated?

Patients taking direct thrombin inhibitors. Signup and view all the answers

What does the current protocol suggest for monitoring patients after t-PA infusion?

ICU monitoring for 24 hours with repeat neuroimaging if necessary. Signup and view all the answers

Which of the following groups is recommended to receive alteplase therapy?

Patients with acute myocardial infarction. Signup and view all the answers

What was the incidence of symptomatic intracranial hemorrhage in low dose alteplase according to the ENCHANTED trial?

1.0% Signup and view all the answers

What constitutes a major risk when considering the use of alteplase therapy?

Potential for intracranial hemorrhage. Signup and view all the answers

Which of the following symptoms is NOT a contraindication for administering alteplase?

Pregnancy. Signup and view all the answers

What immediate action is recommended upon diagnosing symptomatic intracerebral hemorrhage (ICH)?

Transfuse with 10 U of cryoprecipitate intravenously Signup and view all the answers

Which criteria indicate a candidate for mechanical thrombectomy?

Proximal LVO M1 branch of MCA or similar vessels Signup and view all the answers

Which treatment approach showed a higher likelihood of achieving 3-month functional independence?

Dual therapy Signup and view all the answers

What is recommended for reversal of anticoagulation in patients with an INR greater than 1.4?

Give IV Vitamin K or prothrombin complex concentrate Signup and view all the answers

What is the best surgical approach for treating supratentorial ICH with neurological deterioration?

Minimally invasive surgical approach Signup and view all the answers

Which of the following does NOT represent a common complication following spontaneous ICH?

Hypertension Signup and view all the answers

What condition is characterized by the inability to recognize objects, persons, or sounds while sensory functions are intact?

Agnosia Signup and view all the answers

Which treatment is indicated for symptomatic management of intracranial pressure due to hemorrhagic stroke?

Hypertonic saline or mannitol Signup and view all the answers

Study Notes

Stroke

Fifth leading cause of death in the US
5-10% in-hospital mortality rate for ischemic stroke
40-60% in-hospital mortality rate for hemorrhagic stroke
Only 10% of stroke survivors will recover completely
87% of all strokes are ischemic in origin
13% of all strokes are hemorrhagic strokes
Stroke is defined as any vascular injury that impairs cerebral blood flow to a specific region of the brain, retina, or spinal cord, causing neurologic impairment.

Transient Ischemic Attack (TIA)

Transient episode of neurologic dysfunction caused by focal brain, spinal cord, or retinal ischemia, without acute infarction
10% of TIA patients will have a stroke within 90 days

Risk Factors for Stroke After TIA

Hypertension
Diabetes mellitus
Symptoms lasting ≥ 10 minutes
Motor deficits
Speech impairment

Stroke Treatment

Low-risk TIA (ABCD2 score < 4) or moderate to major ischemic stroke (NIHSS > 3): Treatment with aspirin alone
High-risk TIA (ABCD2 score ≥ 4) or minor ischemic stroke (NIHSS score ≤ 3): Treatment with aspirin plus clopidogrel or aspirin plus dipyridamole

CT Head Mnemonic

Blood: Blood in the cisterns/cortical gyral surface (subarachnoid hemorrhage)
Can: Four key cisterns (Circummesencephalic, Suprasellar, Quadrigeminal and Sylvian)
Be: Brain symmetry. Check for effacement of sulci (unilateral or bilateral).
Grey-white differentiation
Shift
Hyper/hypodensity
Very: Ventricles for dilation or compression/shift. Vessels for signs of clot (hyperdense vessel)
Bad: Bone

Anterior Circulation Stroke

Progress within the first 24 hours
Rarely includes loss of consciousness (LOC)
Frontal lobe function: Arousal change (AMS) coupled with impaired judgment and insight
Paralysis and hypesthesia of the lower limb contralaterally
Ipsilateral Hemianopsia
Agnosia (dominant stroke)
Aphasia (dominant stroke)

Posterior Circulation Stroke

Progress for up to 3 days
LOC + Nausea/Vomiting (N/V)
Brain stem + cerebellum: Vertigo, dysphagia, spasticity, ataxia, or nystagmus
Bowel and bladder incontinence (Anterior Cerebral Artery [ACA])
Crossed deficits
Homonymous hemianopsia
Visual agnosia
Alexia + dysarthria

Hemorrhagic Stroke

Clinical presentation can be identical to ischemic stroke
30-day mortality rate of up to 50%
HTN and cerebral amyloid angiopathy are the most common risk factors

Pre-Hospital Stroke Assessment:

Transport to a comprehensive stroke center if travel time is < 15 minutes longer than the closest primary stroke center

Stroke Centers

Acute Stroke Ready Hospitals (ASRH): Establish initial stroke diagnosis and provide initial care
Primary Stroke Centers (PSC): Offer stroke infrastructure (stroke team, stroke unit, patient care protocols & support services, including CT & lab testing availability)
Comprehensive Stroke Centers (CSC): Offer advanced imaging modalities, perform surgical & endovascular interventions & have a stroke unit & stroke registry

ABCD2 Score & Neurological Assessment in the ED

The ABCD2 score is a risk assessment tool for TIA that helps determine the likelihood of a stroke within 90 days.

Stroke Mimics

Stroke should be considered in patients presenting with sudden onset of neurological deficits, but other conditions can mimic stroke.

Diagnosis

CBC
Urea and electrolytes (U&E)
KFT, LFT
RBS
ECG
CT head and CT contrast

NIHSS Scoring (National Institutes of Health Stroke Scale)

Rapid and useful tool
Assesses neuro-deficit
Determines treatment options (fibrinolytic vs. null)
Identifies those at risk for hemorrhage

CT Brain

Subtle, early ischemic changes:
- Hyperdense artery sign (acute thrombus in a vessel)
- Sulcus effacement
- Loss of the insular ribbon
- Loss of gray-white interface
- Mass effect
- Acute hypodensity
Only acute hypodensity & mass effect are associated with an increased risk of intracranial hemorrhage (ICH)

Management

Airway always first
Avoid dehydration and be cautious to avoid fluid overload
Avoid hypothermia (<39C) as it is associated with increased in-hospital mortality
Maintain oxygen saturation >95%
Maintain blood glucose level between 140-180 mg/dl (hyperglycemia during the first 24 hours after stroke is associated with worse outcomes)

Blood Pressure Control

tPA: Less than 185/110
No tPA: Less than 220/120 or MAP 130

Reperfusion Therapy

IV thrombolytic therapy
Mechanical thrombectomy

Thrombolytic Therapy

**Eligibility Recommendations for IV Alteplase in Pts. with AIS **
Age: >18 & < 80 yrs (for 0-3 hr window  > 80 yrs still a candidate for tPA)
NIHSS ≤ 25
No history of both DM & prior stroke
Early changes

Contraindications to IV Thrombolytic Therapy

Time of onset > 3 or 4.5 hours
History of or acute ICH
Ischemic stroke, head trauma, intracranial/spinal surgery within 3 months
Subarachnoid hemorrhage (SAH)
BP > 185/110
GI/GU bleed within 21 days
Coagulopathy (INR > 1.7, platelets < 100,000)
Treatment-dose LMWH within 24 hrs or DOAC use within 48 hrs

Thrombolytic Therapy: Medications

Alteplase: 0.9 mg/kg (maximum dose 90 mg) given over 60 minutes, with initial 10% bolus over 1 minute
Tenecteplase: 0.25 mg/kg (maximum dose 25 mg) given in a single bolus

ENCHANTED Trial

Low dose alteplase (0.6 mg/kg IV) was non-inferior to standard dose tPA (0.9 mg/kg IV) with respect to death and disability at 90 days.
There were significantly fewer symptomatic IC in low dose (1.0%) compared to standard dose (2.1%).

EXTEND-IA TNK Trial

Tenecteplase was associated with a higher incidence of reperfusion and better functional outcome compared to alteplase.
ICH was similar in both groups.

Thrombolytic Therapy in Patients on Anticoagulants

IV alteplase should not be administered to patients who have received a full treatment dose of low molecular weight heparin within the previous 24 hours.

Symptomatic Intracerebral Hemorrhage Following Thrombolysis

Frequently occurs within 36 hours after tPA infusion.
Half of the events are diagnosed within 5 to 10 hours.
Current protocols include ICU monitoring for 24 hours with repeat neuroimaging if there is any neurological deterioration.

Symptomatic ICH Treatment

Cardiovascular & respiratory support
BP management
Neurological monitoring
Prevention of hematoma expansion
Control of elevated intracranial pressure (ICP)
Seizure control
If symptomatic ICH is diagnosed, consider immediately sending a fibrinogen level and empirically transfusing with 10U cryoprecipitate intravenously over 10 to 30 minutes.

Risk Factors for ICH

Patient time of last seen normal is less than 24 hours
Proximal LVO (M1 branch of MCA, ICA, basilar artery)
Moderate to severe stroke symptoms
Meeting DAWN or DEFUSE3 eligibility criteria
Other inclusion criteria as determined by Neurology and Interventional Radiology

Mechanical Thrombectomy

Comparing thrombectomy alone vs. dual therapy (thrombectomy + IV tPA). Dual therapy was associated with a higher likelihood of 3-month functional independence and lower odds of 3-month mortality.
The 2 groups did not differ in symptomatic ICH.
No randomized control trials on mechanical thrombectomy for posterior circulation LVO.

Hemorrhagic Stroke Management

Evidence from clinical trials to guide management for spontaneous ICH has lagged behind that of ischemic stroke and aneurysmal SAH.
Intensive monitoring of airway, BP, ICP control, seizure and herniation

Reversal of Anticoagulation

Vitamin K antagonist and INR > 1.4: IV Vitamin K or 3,4 PCC, FFP
Dabigatran: Idarucizumab, PCC, FFP
Factor Xa inhibitors: Andexanet alfa, 4 PCC
COX inhibitors or ADP receptors inhibitors: Desmopressin
Platelet transfusion?: Consider

ICP Management

Treat with hypertonic saline (HTS) or mannitol.
Some trials showed HTS is more effective than mannitol.
Avoid hypo or hyperglycemia.
Avoid fever.
Corticosteroids are not recommended.
Sedation & seizure control.

Surgical Evacuation

Indicated in: supratentorial ICH, neurological deterioration, coma, midline shift, or high ICP refractory to medical management.
Minimally invasive surgical approach is better than open craniotomy and improved in-hospital mortality.

Key Terms:

Agnosia: Inability to recognize objects, persons, sounds, shapes, or smells, while the specific sense is not defective, nor is there any significant memory loss.
Aphasia: Inability to comprehend or formulate language because of damage to specific brain regions.
Visual Agnosia: The inability to recognize seen objects.

Stroke

Stroke is a medical emergency that happens when the blood supply to the brain is interrupted, causing brain cells to die
Stroke is the fifth leading cause of death in the United States
87% of strokes are ischemic strokes, caused by a blood clot blocking an artery in the brain
13% of strokes are hemorrhagic strokes caused by a bleed in the brain
10% of stroke survivors will recover completely
In-hospital mortality rate is 5%-10% for ischemic stroke and 40%-60% for hemorrhagic stroke

Transient Ischemic Attack (TIA)

TIA is a temporary disruption of blood flow to the brain that causes neurological symptoms but does not cause permanent damage
Patients with TIA symptoms for more than 10 minutes are at risk for a stroke within 90 days
Common symptoms of a TIA include: sudden weakness, numbness, difficulty speaking, vision problems, and dizziness

ABCD2 score

ABCD2 score is used to assess risk of stroke after TIA
A score of 4 or higher indicates high risk of stroke
High-risk TIA patients should be treated with medications in addition to aspirin

CT Head Scan

CT head scan is the primary imaging test for stroke
CT scan can identify most forms of intracranial hemorrhage greater than 1 cm in size
CT scan has limited sensitivity for posterior stroke
CT scan is often unhelpful in the first 3-6 hours of ischemic stroke, but may show signs of ischemic damage within 6-12 hours.

Neurological Assessment

NIHSS (National Institutes of Health Stroke Scale) is a tool used to assess the severity of neurological deficits associated with stroke
NIHSS score is used to guide treatment options
Early ischemic changes include:
- Hyperdense artery sign (acute thrombus in a vessel)
- Sulcus effacement
- Loss of the insular ribbon
- Loss of the gray-white interface
- Mass effect
- Acute hypodensity
Only acute hypodensity and mass effect are associated with an increased risk of ICH

Stroke Management

Airway management is always the first priority for stroke patients
Avoid dehydration and fluid overload
Maintain oxygen saturation above 95%
Keep blood glucose levels between 140-180 mg/dL
Control blood pressure for patients receiving tpa
Hyperglycemia in the first 24 hours of a stroke can lead to worse outcomes

Reperfusion Therapy

Reperfusion therapy aims to restore blood flow to the affected area of the brain
IV thrombolytic therapy (tPA) and mechanical thrombectomy are the two primary reperfusion therapies

Thrombolytic Therapy (tPA)

tPA is a medication that dissolves blood clots
tPA is given intravenously
Time of onset (when symptoms started) is a key criteria for eligibility
tPA must be given within 3 or 4.5 hours of symptom onset, depending on a number of other criteria
Contraindications to tPA administration include severe BP, recent trauma or surgery, and previous stroke
Alternatives to tPA include aspirin and clopidogrel

Mechanical Thrombectomy

Mechanical thrombectomy is a procedure to remove a blood clot from a blood vessel in the brain
Thrombectomy is a minimally invasive procedure that is performed in a specialized stroke center
Thrombectomy is appropriate for patients presenting with large vessel occlusion stroke
Thrombectomy is an effective treatment option, despite its limitations

Symptomatic Intracerebral Hemorrhage (ICH)

Symptomatic ICH is a serious complication that can occur after tPA
ICH is a bleed in the brain that can lead to neurological deterioration and death
Risk factors for ICH include:
- Patient time of last seen normal - less than 24 hours
- Proximal LVO - (M1 branch of MCA, ICA, basilar artery)
- Moderate to severe stroke symptoms
- Meeting DAWN or DEFUSE3 eligibility criteria
Management of ICH:
- Cardiovascular and respiratory support
- BP management
- Neurological monitoring
- Prevention of hematoma expansion
- Control of elevated ICP
- Seizure control
Once symptomatic ICH is diagnosed, consider immediately sending a fibrinogen level and empirically transfusing with 10 U cryoprecipitate intravenously over 10 to 30 minutes.

Hemorrhagic Stroke

Hemorrhagic stroke is a bleed in the brain that can be caused by a variety of factors
Hemorrhagic stroke is often mistaken for ischemic stroke
Common risk factors for hemorrhagic stroke:
- High blood pressure
- Cerebral amyloid angiopathy
Hemorrhagic stroke is a serious condition with a significant mortality rate
Management of hemorrhagic stroke includes intensive monitoring, BP control, ICP management, seizure control, and prevention of herniation

Stroke Mimics

Stroke mimics are conditions that can cause similar symptoms to stroke, but are not actually related to a stroke
Some common stroke mimics include:
- Migraine
- Seizure disorders
- Hypoglycemia
- Subdural hematoma
- Toxic or drug-induced encephalopathy
It is important to rule out stroke mimics to ensure that the patient receives appropriate treatment

Other Important Points

Amaurosis fugax is a condition that can be caused by a blood clot in the ophthalmic artery, resulting in temporary vision loss
Agnosia is the inability to recognize objects, persons, sounds, shapes, or smells while the senses are not defective
Aphasia is the inability to understand or produce language due to damage to specific areas of the brain
Visual agnosia is the inability to recognize seen objects
All patients with suspected stroke should be transported to a stroke center, ideally a comprehensive stroke center
Patients not eligible for tPA should receive aspirin within 24 - 48 hours of symptom onset

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Description

Explore the critical information about strokes and transient ischemic attacks (TIA) in this quiz. Learn about the statistics, definitions, risk factors, and treatment options associated with these neurological events. This quiz will enhance your understanding of the impact of strokes on health and the necessary response strategies.