How should an adult with acute ischemic stroke be managed from initial assessment through imaging, eligibility for intravenous alteplase (tissue plasminogen activator) and mechanical thrombectomy, blood pressure and glucose control, antiplatelet and statin therapy, and secondary prevention?

Management of Acute Ischemic Stroke

Immediate Assessment and Stabilization

All patients with suspected acute ischemic stroke require immediate brain imaging with non-contrast CT to exclude hemorrhage, followed by rapid assessment for reperfusion therapy eligibility within strict time windows. 1, 2

Initial Evaluation (Door-to-Imaging Goal: <20 minutes)

• Secure airway, breathing, and circulation; provide supplemental oxygen only if saturation <94% 1, 3
• Assess neurological deficit using NIHSS score in the emergency department 1, 2
• Check capillary blood glucose immediately—treat hypoglycemia (<60 mg/dL or 3.3 mmol/L) with IV dextrose before any other intervention 1
• Correct hypotension and hypovolemia to maintain mean arterial pressure >70 mmHg for adequate cerebral perfusion 1

Essential Laboratory Studies (Do Not Delay Imaging)

• Complete blood count, serum electrolytes, creatinine, INR/PTT, and troponin 1
• ECG to identify atrial fibrillation or acute coronary syndrome 1
• Only blood glucose assessment must precede alteplase administration 1

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Neuroimaging Protocol

For All Patients (Within 20 Minutes of Arrival)

• Non-contrast CT of the head is mandatory first-line imaging to exclude intracranial hemorrhage 1, 2
• NCCT is preferred over MRI because it is faster and widely available, preventing treatment delays 1, 2

For Thrombectomy Candidates (Presenting Within 6-24 Hours)

• CT angiography from aortic arch to vertex should be performed immediately after NCCT to identify large vessel occlusion 1, 2
• CT perfusion or MRI with diffusion-weighted imaging is required for patients presenting 6-24 hours after last known well to assess core-penumbra mismatch 1, 2

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Intravenous Alteplase (tPA)

Dosing and Administration

Administer alteplase 0.9 mg/kg (maximum 90 mg) with 10% as IV bolus over 1 minute, then 90% infused over 60 minutes. 1, 4

Time Windows and Eligibility

0-3 Hour Window (Class I, Level A Evidence):

• All patients ≥18 years with measurable neurological deficit 1
• No upper age limit—octogenarians receive same benefit 1
• No NIHSS score threshold—severe strokes (NIHSS >25) still benefit despite higher hemorrhage risk 1

3-4.5 Hour Window (Class I, Level B-R Evidence):

• Same criteria as 0-3 hours, but exclude patients with: 1
  • Age >80 years (though recent data suggest this exclusion may not be justified) 1
  • Combined history of diabetes AND prior stroke
  • NIHSS >25
  • Oral anticoagulant use regardless of INR

4.5-9 Hour Window (Extended Window):

• Consider alteplase for patients with CT/MRI perfusion mismatch when thrombectomy is not indicated 1
• For wake-up strokes with DWI-FLAIR mismatch on MRI, alteplase can be given within 4.5 hours of symptom recognition 1

Critical Pre-Treatment Requirements

Blood Pressure:

• Must lower BP to <185/110 mmHg before initiating alteplase 1, 4
• Maintain BP <180/105 mmHg for 24 hours post-treatment 1, 4
• Use IV labetalol or nicardipine for rapid, titratable control 1

Imaging Criteria:

• No intracranial hemorrhage on CT/MRI 1
• Early ischemic changes should not exceed one-third of MCA territory (frank hypodensity is a contraindication) 1
• ASPECTS score ≥6 1

Absolute Contraindications

• Intracranial hemorrhage on imaging 1
• Ischemic stroke within past 3 months 1
• Severe head trauma within 3 months 1
• Unclear or unwitnessed symptom onset >4.5 hours from last known well (unless DWI-FLAIR mismatch present) 1
• Extensive hypodensity (>1/3 MCA territory) on CT 1

Post-Alteplase Management

• Avoid all antithrombotic therapy (aspirin, heparin, anticoagulants) for 24 hours 1, 4
• Monitor neurologically every 15 minutes during infusion, then hourly for 6 hours 1
• Obtain emergent CT if neurological deterioration, severe headache, or hypertension occurs 1

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Mechanical Thrombectomy

Indications (0-6 Hour Window)

Perform thrombectomy for patients meeting ALL criteria: 1

• Age ≥18 years
• Pre-stroke mRS 0-1
• Internal carotid artery or MCA-M1 occlusion on CTA
• NIHSS ≥6
• ASPECTS ≥6
• Groin puncture achievable within 6 hours of symptom onset

Extended Window (6-24 Hours)

Thrombectomy is indicated for anterior circulation large vessel occlusion with favorable imaging: 1

• CT perfusion or MRI showing substantial core-penumbra mismatch 1
• Small ischemic core relative to clinical deficit or hypoperfusion volume 1

Key Principles

• Do NOT wait to assess alteplase response before proceeding to angiography—both treatments should run in parallel 1
• Administer IV alteplase even if thrombectomy is planned (bridging therapy) 1
• Technical goal is mTICI 2b/3 reperfusion 1
• Transfer to comprehensive stroke center if thrombectomy capability unavailable 2

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Blood Pressure Management

For Alteplase-Eligible Patients

• Lower BP to <185/110 mmHg before alteplase, maintain <180/105 mmHg for 24 hours after 1, 4
• Use IV labetalol (10-20 mg over 1-2 minutes, may repeat) or nicardipine infusion (5 mg/hour, titrate by 2.5 mg/hour every 5-15 minutes, max 15 mg/hour) 1

For Non-Thrombolysis Patients

• Permissive hypertension is recommended—do NOT lower BP unless: 1, 2
  • Systolic BP >220 mmHg or diastolic BP >120 mmHg
  • Concomitant acute myocardial infarction, aortic dissection, or preeclampsia/eclampsia 1, 3
• If treatment required, reduce BP by 15-25% in first 24 hours 2
• Avoid aggressive BP lowering—cerebral perfusion is pressure-dependent in acute stroke 2

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Glucose Management

Treat hyperglycemia to achieve blood glucose 140-180 mg/dL during the first 24 hours. 1

• Persistent hyperglycemia >180 mg/dL is associated with worse outcomes and increased hemorrhagic transformation 1
• Hypoglycemia (<60 mg/dL) must be treated immediately with IV dextrose 1
• Closely monitor to prevent hypoglycemia, which can mimic stroke symptoms 1

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Temperature Management

• Actively prevent fever (>37.7°C) with antipyretics and cooling measures 1
• Continuous core temperature monitoring is recommended 1
• Therapeutic hypothermia is NOT recommended outside clinical trials—it increases pneumonia risk without proven benefit 1

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Antiplatelet and Anticoagulation Therapy

Acute Phase (First 24 Hours)

• Do NOT administer aspirin, clopidogrel, or anticoagulants for 24 hours after alteplase 1, 4
• For patients NOT receiving alteplase, aspirin 325 mg should be given within 24-48 hours 2

After 24 Hours Post-Alteplase

• Initiate aspirin 81-325 mg daily or clopidogrel 75 mg daily 2
• Dual antiplatelet therapy (aspirin + clopidogrel) for 21 days may be considered for minor stroke (NIHSS ≤3) or high-risk TIA, then transition to monotherapy 2

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Statin Therapy

Initiate high-intensity statin therapy (atorvastatin 80 mg or rosuvastatin 20-40 mg) during hospitalization for all patients with atherosclerotic stroke. 2

• Early statin initiation is safe and improves long-term outcomes 2
• Continue regardless of baseline LDL cholesterol level 2

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Secondary Prevention Workup

Vascular Imaging

• CT angiography or MR angiography of head and neck vessels to identify carotid stenosis, dissection, or other vascular pathology 1, 2
• Carotid duplex ultrasound is an alternative for extracranial carotid assessment 1

Cardiac Evaluation

• Prolonged cardiac monitoring (≥24 hours) to detect paroxysmal atrial fibrillation 2
• Echocardiography (transthoracic or transesophageal) to identify cardioembolic sources 2

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Special Situations and Pitfalls

Seizures at Stroke Onset

• Treat acute seizures with short-acting benzodiazepines (lorazepam 2-4 mg IV) if not self-limited 2, 3
• Do NOT use prophylactic anticonvulsants—no benefit and may impair recovery 2, 3
• Single self-limited seizure within 24 hours does not require long-term anticonvulsant therapy 2

Patients on ECMO

• Alteplase is contraindicated in ECMO patients due to extreme bleeding risk with systemic anticoagulation 1
• Mechanical thrombectomy should be pursued for large vessel occlusion after multidisciplinary discussion 1

Wake-Up Stroke

• Use MRI with DWI-FLAIR mismatch to identify patients eligible for alteplase within 4.5 hours of symptom recognition 1
• If MRI unavailable or shows no mismatch, proceed directly to thrombectomy evaluation if within 24 hours 1

Common Errors to Avoid

• Never delay alteplase for "complete" laboratory results—only glucose is required 1
• Never withhold alteplase from patients taking single or dual antiplatelet therapy—benefit outweighs small increased hemorrhage risk 1
• Never aggressively lower BP in non-thrombolysis candidates—permissive hypertension maintains collateral flow 2, 3
• Never give aspirin before brain imaging excludes hemorrhage 3