I have rich content now. I have the full stroke chapter covering: epidemiology, pathophysiology, prehospital care, ischemic stroke syndromes, hemorrhagic stroke, diagnosis, general treatment, BP control, alteplase criteria, thrombectomy, and cerebellar/brainstem stroke. Let me now compile the comprehensive notes and viva questions.
Tintinalli's Emergency Medicine 9th Edition - Chapter 167
STROKE SYNDROMES
PG Notes & Viva Questions
SECTION 1: INTRODUCTION & EPIDEMIOLOGY
- 795,000 strokes per year in the USA (one every 40 seconds; one death every 4 minutes)
- 77% primary strokes; 23% recurrent strokes
- Financial burden: $33.9 billion (2012-2013)
- Age-adjusted stroke death rate fell 28.7% (2004-2014)
- Treatments driving improvement: stroke units, thrombolysis, mechanical thrombectomy, expanding treatment windows
SECTION 2: PATHOPHYSIOLOGY & ANATOMY
Definition
Stroke = any disease process that interrupts blood flow to the brain, leading to loss of oxygen and glucose for high-energy phosphate production + secondary cellular injury mediators + edema/mass effect.
Stroke Types & Proportions
| Type | % of All Strokes |
|---|
| Ischemic | 87% |
| Intracerebral hemorrhage (ICH) | 10% |
| Subarachnoid hemorrhage (SAH) | 3% |
Ischemic Stroke - Causes
- Thrombotic - in situ thrombus on atherosclerotic plaque
- Embolic - cardioembolism (AF, valvular disease), artery-to-artery embolism
- Hypoperfusion - systemic hypotension, cardiac arrest
Vascular Anatomy
- Anterior circulation: Internal carotid artery (ICA) → Middle cerebral artery (MCA) + Anterior cerebral artery (ACA)
- Posterior circulation: Vertebral arteries → Basilar artery → Posterior cerebral artery (PCA), PICA, AICA, SCA
- Clinical findings determined by location of lesion + degree of collateral circulation
Ischemic Penumbra
- Core of dead neurons surrounded by ischemic penumbra (viable but at-risk tissue)
- Neurons die within minutes of complete cessation of perfusion
- Treatment goal: rapid reperfusion to salvage penumbra
SECTION 3: PREHOSPITAL CARE
Prehospital Stroke Scales (Table 167-3)
| Scale | Components | Notes |
|---|
| Cincinnati Prehospital Stroke Scale (CPSS) | Facial droop, arm drift, abnormal speech | Any 1 of 3 = high suspicion |
| Los Angeles Prehospital Stroke Screen (LAPSS) | Age >45, no seizure history, symptom onset <24h, not wheelchair-bound, glucose 60-400, asymmetric face/arm/grip | |
| Melbourne Ambulance Stroke Screen (MASS) | Combined CPSS + LAPSS elements | |
Large Vessel Occlusion (LVO) Detection
- Multiple prehospital scales developed (none with high specificity AND sensitivity)
- No single prehospital LVO scale recommended for routine use yet
- Goal: route LVO patients to comprehensive stroke centers capable of thrombectomy
Key Prehospital Actions
- Rapid recognition and transport ("time is brain")
- Pre-notification of receiving hospital
- Establish time of last known well (LKW) - most critical piece of information
- IV access, ECG monitoring, glucose check
SECTION 4: CLINICAL FEATURES - ISCHEMIC STROKE SYNDROMES
General Principles
- Stroke = sudden onset neurologic deficit
- Location of lesion determines clinical syndrome
- NIHSS (National Institutes of Health Stroke Scale) = standard severity quantification
NIHSS Scoring (Table 167-6)
Scores 11 domains: consciousness, gaze, visual fields, facial palsy, arm/leg motor, limb ataxia, sensory, language, dysarthria, extinction/inattention
- 0 = no deficit
- 1-4 = minor stroke
- 5-15 = moderate stroke
- 16-20 = moderate-severe
- 21-42 = severe stroke
A. Anterior Circulation Strokes
1. Middle Cerebral Artery (MCA) - Most Common
- Contralateral hemiplegia (face and arm > leg)
- Contralateral hemisensory loss
- Homonymous hemianopia
- Gaze deviation toward the lesion ("eyes look at the stroke")
- Dominant hemisphere (usually left): Aphasia (Broca's = expressive; Wernicke's = receptive; Global = both)
- Non-dominant hemisphere (usually right): Neglect, anosognosia, constructional apraxia
- Superior division MCA: Broca's aphasia + arm weakness
- Inferior division MCA: Wernicke's aphasia + visual field defect
- Large MCA territory stroke → malignant MCA syndrome (massive edema, herniation)
2. Anterior Cerebral Artery (ACA)
- Contralateral leg weakness > arm (reversed from MCA)
- Frontal lobe signs: abulia, urinary incontinence, personality change
- Grasp reflex
3. Internal Carotid Artery (ICA)
- Variable depending on collaterals; can mimic large MCA or combined MCA+ACA territory
- Ipsilateral monocular blindness (amaurosis fugax if TIA) - from ophthalmic artery
B. Posterior Circulation Strokes
1. Posterior Cerebral Artery (PCA)
- Contralateral homonymous hemianopia (most common) - with macular sparing
- Cortical blindness (bilateral PCA)
- Thalamic involvement: hemisensory loss, thalamic pain syndrome
- Dominant: alexia without agraphia, anomia
2. Basilar Artery (most dangerous)
- "Locked-in syndrome": quadriplegia + anarthria + preserved consciousness; only vertical eye movements preserved
- Coma (if tegmentum involved)
- Cranial nerve palsies + contralateral long tract signs = "crossed signs" (hallmark of brainstem stroke)
- Diplopia, dysarthria, dysphagia, vertigo, ataxia
3. PICA (Posterior Inferior Cerebellar Artery) - Lateral Medullary Syndrome (Wallenberg's)
Classic findings (PICA mnemonic: AIVD):
- Ataxia (ipsilateral limb/gait)
- Ipsilateral Horner's syndrome (ptosis, miosis, anhidrosis)
- Ipsilateral facial pain/numbness (descending trigeminal)
- Vertigo, nausea, vomiting, hiccups, dysphagia
- Dissociated sensory loss: ipsilateral face + contralateral body (spinothalamic)
- NO hemiplegia (corticospinal tracts spared)
4. AICA (Anterior Inferior Cerebellar Artery)
- Lateral inferior pontine syndrome
- Ipsilateral: facial weakness, facial numbness, deafness/tinnitus (cochlear involvement), Horner's
- Contralateral: body pain/temperature loss
5. Cerebellar Stroke
- Sudden onset vertigo, nausea, vomiting, truncal ataxia, inability to walk
- Headache common
- CRITICAL: Cerebellar edema → obstructive hydrocephalus → tonsillar herniation (life-threatening)
- May be initially misdiagnosed as labyrinthitis
- Distinguishing from labyrinthitis: inability to walk, direction-changing nystagmus, HINTS exam
6. Lacunar Infarcts
- Small vessel disease in basal ganglia, thalamus, internal capsule, pons
- Classic syndromes:
- Pure motor hemiplegia (posterior limb of internal capsule/basis pontis)
- Pure sensory stroke (thalamus - VPL nucleus)
- Ataxic hemiparesis (posterior limb of internal capsule/pons)
- Dysarthria-clumsy hand (pons/genu of internal capsule)
- Sensorimotor stroke (thalamocapsular)
C. Transient Ischemic Attack (TIA)
- Traditional definition: focal neurologic deficit lasting <24 hours
- Modern definition (tissue-based): <1 hour, no infarction on DWI
- Two-day stroke risk after TIA: 3-10% (highest in first 24-48 hours)
- ABCD² score for risk stratification:
- Age ≥60 (1 pt)
- Blood pressure ≥140/90 (1 pt)
- Clinical features: unilateral weakness (2), speech without weakness (1)
- Duration: ≥60 min (2), 10-59 min (1)
- Diabetes (1)
- Score 0-3 = low risk; 4-5 = moderate; 6-7 = high
SECTION 5: HEMORRHAGIC STROKE SYNDROMES
A. Intracerebral Hemorrhage (ICH)
- 10% of all strokes; highest 30-day mortality (~40%)
- Most common causes: hypertension (#1), amyloid angiopathy (#2 in elderly), anticoagulation, AVM, tumor
Hypertensive ICH - Locations
| Location | Frequency | Features |
|---|
| Putamen | Most common (~35%) | Contralateral hemiplegia, gaze deviation toward lesion |
| Thalamus (~20%) | | Contralateral hemisensory, gaze deviation downward ("setting sun") |
| Cerebellum (~16%) | | Ataxia, headache, vomiting - danger of herniation |
| Pons (~10%) | | Quadriplegia, pinpoint pupils, high fever, coma |
| Lobar (~30%) | Usually amyloid angiopathy | Variable depending on location |
ICH Score (Predicts mortality)
- GCS (3-4 = 2pts; 5-12 = 1pt; 13-15 = 0pts)
- ICH volume ≥30 cm³ (1 pt)
- Intraventricular extension (1 pt)
- Infratentorial origin (1 pt)
- Age ≥80 (1 pt)
- Score 0 = ~0% mortality; Score 5-6 = ~100% mortality
ICH Management
- Airway: Intubate if GCS ≤8 or declining
- BP control: Target SBP <140 mmHg (AHA 2015: 140-150 range acceptable; aggressive lowering to 140 safe but may not improve outcomes vs. 180 target)
- Reverse anticoagulation immediately:
- Warfarin → Vitamin K + 4-factor PCC (preferred) or FFP
- Dabigatran → Idarucizumab (Praxbind)
- Factor Xa inhibitors → Andexanet alfa or 4-factor PCC
- Heparin → Protamine sulfate
- No role for recombinant Factor VIIa (increases clotting but not outcomes)
- Surgical evacuation: cerebellar hematoma >3 cm or with hydrocephalus/brainstem compression; supratentorial controversial
- ICP management: Head of bed 30°, osmotherapy (mannitol), consider ICP monitor
B. Subarachnoid Hemorrhage (SAH)
- 3% of all strokes; most common cause: ruptured aneurysm (80%)
- Peak age: 40-60 years; females > males
- Risk factors: smoking, hypertension, family history, polycystic kidney disease, connective tissue disorders
Classic Presentation
- "Thunderclap headache": worst headache of life, sudden onset, reaching maximum intensity within seconds to 1 minute
- Neck stiffness, photophobia
- Loss of consciousness at onset in ~50%
- Sentinel headache (warning leak): 10-40% have headache days to weeks before major bleed
Diagnosis
- Non-contrast CT: 98% sensitive within 6 hours; sensitivity drops to ~93% at 24h
- Lumbar puncture: if CT negative but clinical suspicion high - look for xanthochromia (12h-2 weeks after onset) or RBCs that don't clear between tubes
- CT Angiography or conventional digital subtraction angiography (DSA): identify aneurysm
Grading
- Hunt & Hess Scale (clinical): Grade I-V
- Fischer Grade (radiologic on CT): Grade 1-4 (Grade 3 = highest vasospasm risk)
SAH Management
- Nimodipine 60 mg q4h × 21 days (reduces vasospasm-related ischemia; does NOT prevent vasospasm)
- Aneurysm: surgical clipping or endovascular coiling (ISAT trial: coiling preferred for suitable anatomy)
- Prevent rebleeding: early aneurysm repair
- Vasospasm (days 4-14): transcranial Doppler monitoring, Triple-H therapy (hypertension, hypervolemia, hemodilution) - now controversial
- Hydrocephalus: ventriculostomy/EVD
- Avoid aggressive BP lowering until aneurysm is secured
SECTION 6: STROKE DIAGNOSIS
Imaging
- Non-contrast CT head: FIRST imaging in all acute stroke patients
- Rules out hemorrhage (before thrombolytics)
- May be normal in first 6 hours of ischemic stroke
- Early signs of ischemia: hyperdense MCA sign, loss of insular ribbon, obscuration of lenticular nucleus, sulcal effacement
- CT Angiography (CTA): detects LVO, aneurysm, dissection
- CT Perfusion (CTP): identifies core infarct vs. penumbra - guides thrombectomy selection (DAWN, DEFUSE 3 trials)
- MRI/DWI: Most sensitive for acute ischemia (detects infarct within minutes); gold standard
- MRA: non-invasive vascular imaging
Stroke Mimics (Must exclude)
- Hypoglycemia (check glucose in ALL patients - #1 mimic)
- Todd's paralysis (post-ictal)
- Complicated migraine (hemiplegic migraine)
- Brain tumor
- Hypertensive encephalopathy
- Subdural hematoma
- Bell's palsy (peripheral VII - forehead sparing in central lesion)
- MS exacerbation
- Conversion disorder
Key Lab Tests
- Serum glucose (immediate - must rule out hypoglycemia)
- CBC, coagulation (PT/INR, PTT, platelets)
- BMP, BUN/creatinine
- Type and screen
- ECG (rule out AF; detect cardiac cause; Wellens-like changes in SAH)
- Troponin
- Urine pregnancy test (women of childbearing age)
SECTION 7: TREATMENT OF ACUTE ISCHEMIC STROKE
General Measures (All patients)
- ABC: Airway, Breathing, Circulation
- IV access × 2, cardiac monitoring, pulse oximetry
- Oxygen: only if SaO₂ <94% (routine supplemental O₂ NOT indicated)
- Glucose: correct hypoglycemia immediately; avoid hyperglycemia (target 140-180 mg/dL)
- Fever: treat aggressively (associated with worse outcomes); use acetaminophen
- Normal saline (not D5W or hypotonic fluids - worsen cerebral edema)
- NPO until swallow evaluation
- Stroke unit admission (proven to reduce complications, length of stay, disability)
- "Drip and ship" if at non-stroke center: give IV tPA then transfer
Blood Pressure Management
Before tPA (if candidate):
- Target: SBP ≤185 / DBP ≤110 mmHg
- Drugs: Labetalol 10-20 mg IV over 1-2 min (repeat ×1) OR Nicardipine infusion 5 mg/h (titrate up by 2.5 mg/h q5-15 min; max 15 mg/h)
After tPA administration:
- Target: SBP <180 / DBP <105 mmHg for 24 hours
- Avoid sudden BP drops (can extend infarct)
In patients NOT receiving tPA:
- Do not lower BP unless SBP >220 or DBP >120 (or other compelling indication like aortic dissection, ACS, hypertensive encephalopathy)
- Permissive hypertension maintains penumbral perfusion
- If BP lowering needed: reduce by no more than 15-25% in first 24 hours
IV Thrombolysis - Alteplase (rtPA)
Dose
- 0.9 mg/kg IV (max 90 mg)
- 10% as bolus over 1 minute
- Remaining 90% infused over 60 minutes
Time Windows
- 0-3 hours: Eligible if inclusion criteria met (broadest eligibility)
- 3-4.5 hours: Extended window with additional restrictions (Table 167-8)
AHA/ASA 2018 Inclusion Criteria (0-3 hours)
- Diagnosis of acute ischemic stroke with measurable deficit
- Age ≥18 years (no upper age limit for <3h window)
- Onset <3 hours from last known well
- NIHSS: no lower limit (even mild disabling strokes may benefit); no upper limit
Additional Criteria for 3-4.5 Hour Window
All of the above PLUS:
- Age >60 years OR no history of both DM AND prior stroke
- NIHSS score ≤25
- No anticoagulant use
- No imaging evidence of ischemic injury >1/3 of MCA territory
Key Exclusion Criteria
- Intracranial hemorrhage on imaging
- SAH symptoms/signs
- Prior intracranial hemorrhage
- Stroke or severe head trauma within 3 months
- Intracranial/intraspinal surgery within 3 months
- GI/urinary tract hemorrhage within 21 days
- SBP >185 / DBP >110 despite treatment
- Platelet count <100,000/mm³
- INR >1.7 / aPTT >40s / PT >15s
- Blood glucose <50 mg/dL (correct first, then reassess)
- Intracranial neoplasm, AVM, or aneurysm
- Aortic arch dissection
Relative Contraindications (use clinical judgment)
- Minor or rapidly improving symptoms (but do not withhold if disabling deficit)
- Seizure at onset (with residual deficit likely from stroke)
- Recent major surgery or trauma within 14 days
- Recent MI within 3 months
- Pregnancy
Complications of tPA
- Symptomatic intracranial hemorrhage: ~6% (vs 0.6% without tPA)
- Systemic hemorrhage
- Angioedema (especially with ACE inhibitors)
- If symptomatic ICH suspected after tPA: STOP infusion, emergent CT, cryoprecipitate (fibrinogen), neurosurgery consult
Endovascular Thrombectomy (EVT / Mechanical Thrombectomy)
Landmark Trials (all published 2015)
- MR CLEAN, ESCAPE, SWIFT PRIME, EXTEND-IA, THRACE
- All showed dramatic benefit of thrombectomy + standard care vs. standard care alone
- NNT as low as 2.6 to improve functional outcome
Indications (AHA/ASA 2018)
- Proximal LVO (ICA, M1 MCA, basilar)
- NIHSS ≥6
- ASPECTS ≥6 (Alberta Stroke Program Early CT Score - 10-point CT scoring; lower = more infarct)
- Pre-stroke mRS 0-1 (independent)
- Can be treated within 6 hours of symptom onset (Class I, Level A)
Extended Window (6-24 hours) - DAWN & DEFUSE 3 Trials
- DAWN trial: 6-24 hours; clinical-imaging mismatch (small core, large penumbra)
- DEFUSE 3 trial: 6-16 hours; perfusion imaging mismatch
- Patient selection by CTP or MR perfusion imaging
- Now recommended as standard of care for eligible patients
Device
- Stent retrievers (Solitaire, Trevo): most common
- Aspiration catheters (ADAPT technique)
- Often combined
tPA + Thrombectomy
- Give IV tPA if eligible AND plan thrombectomy (do not delay tPA for thrombectomy planning)
- Bridging therapy (tPA then thrombectomy) is standard
SECTION 8: SPECIAL CIRCUMSTANCES
Stroke with Concurrent Acute MI
- If ST elevation MI: treat both - PCI for MI; thrombolytics or thrombectomy for stroke as appropriate
- Consider cardiology consultation urgently
Cerebellar/Brainstem Stroke Treatment
- Cerebellar hematoma or large infarct with swelling: urgent neurosurgical consultation
- Hydrocephalus from cerebellar stroke: EVD (external ventricular drain)
- Do NOT give anticoagulation acutely in brainstem stroke (risk of hemorrhagic transformation)
- Posterior fossa decompressive surgery for malignant cerebellar edema
Stroke in Special Populations
- Pregnancy: tPA is relatively contraindicated (fetal risk); thrombectomy preferred where available
- Anticoagulated patients: Reverse anticoagulation before tPA if INR >1.7
- Unknown onset/Wake-up stroke: DWI-FLAIR mismatch on MRI predicts recent onset; eligible for tPA (WAKE-UP trial) and thrombectomy
SECTION 9: SECONDARY STROKE PREVENTION (Initiated in ED)
- Antiplatelet therapy: Aspirin 160-325 mg within 24-48 hours (once hemorrhage excluded and tPA window passed)
- Dual antiplatelet (aspirin + clopidogrel): CHANCE trial - superior to aspirin alone for minor stroke/high-risk TIA (NIHSS ≤3 or ABCD² ≥4) × 21 days, then aspirin alone
- Anticoagulation for AF: Start 3-7 days after moderate stroke; delay in large or hemorrhagic transformation
- Statin therapy: Start high-intensity statin (atorvastatin 80 mg)
- BP control: Long-term target <130/80 mmHg
SECTION 10: DISPOSITION
- All acute stroke patients: Admit to stroke unit (Class I evidence)
- TIA patients: Admit if ABCD² ≥4, AF, carotid stenosis, or cannot ensure rapid follow-up
- If no stroke unit available: Transfer after stabilization and IV tPA ("drip and ship")
- Telestroke: Remote stroke physician via video can guide tPA decisions at spoke hospitals
VIVA QUESTIONS - STROKE SYNDROMES (Chapter 167, Tintinalli 9e)
EPIDEMIOLOGY & PATHOPHYSIOLOGY
Q1. What are the proportions of stroke subtypes?
- Ischemic: 87%, ICH: 10%, SAH: 3%
Q2. What is the ischemic penumbra and why is it important?
- Viable but at-risk brain tissue surrounding the core infarct; target for reperfusion therapy; salvageable if perfused within the time window
Q3. "Time is brain" - quantify this statement.
- ~1.9 million neurons die per minute during a major stroke; every 15-minute delay in treatment reduces functional independence
CLINICAL SYNDROMES
Q4. Where does "eyes look toward the lesion" vs. "eyes look away from the lesion"?
- Eyes look toward the lesion in hemispheric stroke (cortical gaze center destroyed, contralateral gaze center pulls eyes toward lesion)
- Eyes look away from lesion (toward hemiplegia) in brainstem/pontine stroke (PPRF destroyed ipsilaterally)
Q5. Describe Wallenberg's (lateral medullary) syndrome. What artery is involved?
- PICA occlusion; Features: ipsilateral Horner's + ipsilateral facial loss of pain/temperature + ipsilateral limb ataxia + vertigo/dysphagia/hiccups + contralateral body loss of pain/temperature (dissociated sensory loss); NO hemiplegia
Q6. What is "locked-in syndrome" and what structure is affected?
- Ventral pons infarction; patient is quadriplegic and anarthric but conscious; only vertical eye movements preserved (intact midbrain); caused by bilateral corticospinal/corticobulbar tract destruction
Q7. A patient has sudden severe vertigo, cannot walk, has rightward gaze-evoked nystagmus, and normal hearing. What is the most likely diagnosis and dangerous complication?
- Cerebellar infarction (vs. labyrinthitis); dangerous complication = cerebellar edema → obstructive hydrocephalus → tonsillar herniation → death
Q8. What are the 4 classic lacunar syndromes?
- Pure motor hemiplegia (posterior limb internal capsule/basis pontis)
- Pure sensory stroke (thalamic VPL)
- Ataxic hemiparesis (pons/internal capsule)
- Dysarthria-clumsy hand syndrome (pons)
Q9. What is the modern tissue-based definition of TIA?
- Transient neurologic deficit lasting <1 hour with no evidence of infarction on DWI-MRI
Q10. What does the ABCD² score predict and what is a high-risk score?
- Predicts 2-day stroke risk after TIA; score 6-7 = high risk (~8%); score 0-3 = low risk (~1%)
DIAGNOSIS
Q11. What are early CT signs of ischemic stroke?
- Hyperdense MCA sign (thrombus in MCA)
- Loss of insular ribbon
- Obscuration of lenticular nucleus
- Sulcal effacement
- Note: CT may be normal in first 6 hours of ischemic stroke
Q12. What is the ASPECTS score and its significance?
- Alberta Stroke Program Early CT Score (0-10): 10 = normal; lower scores = more infarct burden; score <6 associated with poor outcomes from thrombectomy (relative contraindication)
Q13. What is the most important immediate bedside test in stroke?
- Blood glucose - hypoglycemia is the #1 stroke mimic and must be excluded immediately
Q14. What is HINTS exam and when is it used?
- Head Impulse, Nystagmus, Test of Skew; used to distinguish central (stroke) from peripheral (vestibular neuritis) cause of acute vestibular syndrome
- Central stroke: normal head impulse + direction-changing nystagmus + skew deviation = 100% sensitive for posterior fossa stroke (more sensitive than early MRI)
THROMBOLYSIS (HIGH-YIELD)
Q15. What is the dose of IV alteplase for acute ischemic stroke?
- 0.9 mg/kg (max 90 mg); 10% as IV bolus over 1 min; remaining 90% over 60 min
Q16. A 72-year-old presents 2 hours after onset of right arm weakness. BP is 200/115. Can you give tPA?
- Must lower BP first: target SBP ≤185 / DBP ≤110; use labetalol 10-20 mg IV or nicardipine infusion; once BP controlled, tPA can be given (age is not an exclusion)
Q17. What is the blood pressure target after tPA administration?
- SBP <180 / DBP <105 mmHg for first 24 hours post-tPA
Q18. List 5 absolute exclusion criteria for tPA.
- Any intracranial hemorrhage on imaging
- Prior intracranial hemorrhage history
- Stroke or severe head trauma within 3 months
- Platelet count <100,000/mm³
- Blood glucose <50 mg/dL (before correction)
- INR >1.7
- Aortic arch dissection
Q19. Does NIHSS score have an upper or lower limit for tPA eligibility?
- No upper or lower limit in the 0-3 hour window; both mild disabling strokes and very severe strokes may benefit; rapidly improving symptoms are a relative (not absolute) contraindication
Q20. A patient develops tongue swelling and lip angioedema 30 minutes into tPA infusion. What do you do?
- Stop tPA infusion; this is tPA-associated angioedema (especially with concurrent ACE inhibitor use); manage airway urgently; give antihistamines, steroids, epinephrine as needed
Q21. Symptomatic ICH develops during tPA. Management?
- Stop infusion immediately
- Urgent CT head
- Cryoprecipitate (provides fibrinogen; 10 units IV)
- Neurosurgery consult
- Consider TXA (tranexamic acid), FFP
MECHANICAL THROMBECTOMY
Q22. Name the 5 landmark 2015 trials that established mechanical thrombectomy.
- MR CLEAN, ESCAPE, SWIFT PRIME, EXTEND-IA, THRACE
Q23. What are the criteria for thrombectomy in the standard window?
- LVO (ICA, M1 MCA, basilar)
- NIHSS ≥6
- ASPECTS ≥6
- Pre-stroke mRS 0-1
- Treatable within 6 hours
Q24. Which trials extended the thrombectomy window to 24 hours?
- DAWN (6-24 hours): clinical-imaging mismatch
- DEFUSE 3 (6-16 hours): perfusion imaging mismatch
Q25. Should tPA be withheld if thrombectomy is planned?
- No - give IV tPA if eligible (bridging therapy); do not delay tPA to plan thrombectomy
HEMORRHAGIC STROKE
Q26. What are the most common locations for hypertensive ICH and their clinical features?
- Putamen (most common): contralateral hemiplegia, eyes deviated toward lesion
- Thalamus: hemisensory, "setting sun" eye deviation (downward)
- Cerebellum: ataxia, vomiting, risk of herniation
- Pons: pinpoint pupils, quadriplegia, fever, coma (worst prognosis)
Q27. What is the BP target for ICH management?
- SBP <140 mmHg (AHA 2015); achievable target of 140-150 range; aggressive lowering to 140 is safe but functional benefit over 180 target remains debated
Q28. A patient on warfarin has an ICH with INR 3.8. How do you reverse anticoagulation?
- 4-factor PCC (Kcentra) - preferred (rapid, complete reversal, less volume than FFP)
- PLUS Vitamin K 10 mg IV (for sustained reversal)
- NOT FFP alone (volume, time issues)
Q29. What is the antidote for dabigatran-associated ICH?
- Idarucizumab (Praxbind) - specific reversal agent for dabigatran
Q30. What is the ICH Score and what is its significance?
- Scores GCS, ICH volume ≥30 cm³, intraventricular extension, infratentorial origin, age ≥80; predicts 30-day mortality; Score 5-6 = ~100% mortality
Q31. When is surgical evacuation indicated for ICH?
- Cerebellar hematoma >3 cm or with brainstem compression/hydrocephalus = urgent surgery
- Supratentorial: controversial; STICH trials showed no clear benefit for routine surgery
SAH
Q32. What is the classic presentation of SAH?
- "Thunderclap headache" - worst headache of life, instantaneous onset reaching maximum intensity within seconds; ± loss of consciousness, neck stiffness, photophobia
Q33. CT sensitivity for SAH is 98% in the first 6 hours - what do you do if CT is negative but SAH is suspected?
- Lumbar puncture: look for xanthochromia (yellow discoloration of CSF from RBC breakdown) - reliable from 12 hours to 2 weeks after onset; also RBCs that don't clear between tubes 1 and 4
Q34. What drug reduces vasospasm in SAH and what is the dose?
- Nimodipine 60 mg every 4 hours × 21 days (oral/NG); reduces ischemic complications from vasospasm (does NOT prevent vasospasm itself)
Q35. What trial compared coiling vs. clipping for SAH?
- ISAT trial: endovascular coiling superior to surgical clipping for suitable anatomy (improved independence at 1 year)
SPECIAL SCENARIOS
Q36. A patient wakes from sleep with a left hemiplegia and cannot give a last known well time. Can tPA be given?
- "Wake-up stroke" - use DWI-FLAIR mismatch on MRI (DWI bright + FLAIR normal = infarct <4.5 hours old); eligible for tPA (WAKE-UP trial) or thrombectomy if LVO present (DAWN/DEFUSE 3 criteria)
Q37. What is "drip and ship" in stroke management?
- IV tPA given at a primary stroke center (spoke) while arranging transfer to a comprehensive stroke center (hub) for thrombectomy evaluation; "drip and ship" vs. "mothership" (direct transfer without tPA) debate ongoing
Q38. What secondary prevention strategy is recommended for minor stroke/TIA within 24 hours?
- Dual antiplatelet: Aspirin + clopidogrel (CHANCE trial) for 21 days, then aspirin alone; reduces 90-day stroke risk by ~32%
QUICK REFERENCE TABLES
Stroke Type vs. Key Features
| Feature | MCA | ACA | PCA | Brainstem | Cerebellar |
|---|
| Motor deficit | Arm/face > leg | Leg > arm | None/minimal | Crossed signs | Ataxia |
| Sensory deficit | Contralateral | Contralateral | Contralateral | Dissociated | Minimal |
| Vision | Hemianopia | Normal | Hemianopia | Diplopia | Nystagmus |
| Speech | Aphasia (dominant) | Abulia | Alexia | Dysarthria | Dysarthria |
| Consciousness | Usually preserved | Usually preserved | May be impaired | May be impaired | Usually preserved |
tPA Time Windows
| Window | Eligible Patients |
|---|
| 0-3 hours | Age ≥18, no hemorrhage, measurable deficit |
| 3-4.5 hours | Above + age >60 or no DM+prior stroke, NIHSS ≤25 |
| 4.5+ hours | tPA NOT indicated (thrombectomy if LVO in DAWN/DEFUSE criteria) |
Source: Tintinalli's Emergency Medicine: A Comprehensive Study Guide, 9th edition, Chapter 167 - Stroke Syndromes (authored by Steven Go). Block 14 of the digital library.