What is the recommended emergency management and secondary prevention plan for an adult presenting with an acute ischemic stroke?

Acute Ischemic Stroke: Emergency Management Protocol

Immediate Prehospital Actions (Scene Time ≤15 Minutes)

Emergency medical services must transport suspected stroke patients directly to the nearest stroke-capable center with CT imaging, bypassing non-stroke facilities, while recording the exact time of last known well—the single most critical data point for all treatment decisions. 1

• Perform FAST screening; any positive finding mandates immediate high-priority transport 1
• Record the precise time the patient was last neurologically normal (for wake-up strokes, this is bedtime, not discovery time) 1
• Obtain fingerstick glucose immediately; hypoglycemia (<50 mg/dL) mimics stroke and contraindicates thrombolysis 2, 1
• Establish IV access with normal saline (avoid dextrose-containing fluids unless hypoglycemic) 1
• Provide supplemental oxygen only if saturation <94%; routine oxygen offers no benefit 2, 1
• Initiate cardiac monitoring to detect atrial fibrillation 1
• Do not treat blood pressure in the field unless systolic ≥220 mmHg 1
• Provide detailed pre-notification including last known well time, FAST findings, vital signs, glucose, anticoagulation status, and estimated arrival 1

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Emergency Department Assessment (First 10 Minutes)

Stabilize airway, breathing, and circulation while simultaneously beginning stroke evaluation—do not delay assessment for stabilization unless the airway is compromised. 2

• Intubate if Glasgow Coma Scale ≤8 or inability to protect airway 1
• Draw blood for CBC, coagulation profile (PT/INR, aPTT), metabolic panel, glucose, cardiac biomarkers 3
• Obtain 12-lead ECG to detect atrial fibrillation or acute MI 3
• Calculate NIH Stroke Scale score to quantify severity 2
• Determine exact last known well time (zero-hour for all treatment decisions) 2

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Neuroimaging Protocol (Target: CT Within 25 Minutes)

Perform non-contrast head CT within 25 minutes of arrival and interpret within 45 minutes to exclude hemorrhage; do not delay IV alteplase to obtain advanced imaging in patients within the 3–4.5 hour window. 2, 3

• Non-contrast CT is sufficient to proceed with thrombolysis 2
• Add CT angiography for all patients within 6 hours to identify large vessel occlusion for potential thrombectomy 2
• Early ischemic changes involving >1/3 of a hemisphere do not contraindicate alteplase within 3 hours 3
• CT perfusion may be added in selected cases but must never delay thrombolytic therapy 2, 3

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Blood Pressure Management

For Thrombolysis Candidates (Within 4.5 Hours)

Blood pressure must be reduced to <185/110 mmHg before starting alteplase and maintained ≤180/105 mmHg during and for 24 hours after infusion—failure to achieve this target is an absolute contraindication to thrombolysis. 2, 3

• If systolic 185–230 mmHg or diastolic 105–120 mmHg, give labetalol 10–20 mg IV (may repeat once) or nicardipine infusion starting at 5 mg/h, titrate by 2.5 mg/h every 5–15 minutes (max 15 mg/h) 3
• Monitor BP every 15 minutes for first 2 hours, every 30 minutes for next 6 hours, then hourly up to 24 hours 3

For Non-Thrombolysis Patients

Permissive hypertension is recommended unless systolic >220 mmHg or diastolic >120 mmHg; aggressive lowering may jeopardize penumbral perfusion. 2

• If treatment is required, reduce BP by only 15–25% within the first 24 hours 2, 3
• Antihypertensive therapy initiated when BP <220/120 mmHg does not reduce death or dependency 2

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Intravenous Thrombolysis (Alteplase)

Intravenous alteplase 0.9 mg/kg (maximum 90 mg) is the single most critical intervention for acute ischemic stroke and must be administered within 3–4.5 hours of symptom onset if the patient meets eligibility criteria. 2

Dosing and Administration

• Give 10% as immediate IV bolus over 1 minute, remaining 90% infused over 60 minutes 2
• Target door-to-needle time ≤30 minutes (90th percentile ≤60 minutes) 2
• When guidelines are followed, 37% of patients achieve full independence in daily activities 2
• Every 15-minute reduction in door-to-needle time decreases in-hospital mortality by 5% 2

Absolute Contraindications

• Recent (≤3 months) head trauma or prior stroke 3
• History of intracranial hemorrhage 3
• Clinical features suggesting subarachnoid hemorrhage 3
• Intracranial or spinal surgery within 3 months 3
• Arterial puncture at non-compressible site within 7 days 3
• Uncontrolled BP >185/110 mmHg despite treatment 3
• Active bleeding, platelet count <100×10⁹/L, INR >1.7, PT >15 seconds, or recent heparin with elevated aPTT 3

Critical Pitfall

• Do not withhold thrombolysis solely because NIH Stroke Scale ≥25; severe strokes may still benefit when treated within 4.5 hours 3
• Rapidly improving symptoms warrant withholding alteplase only if the patient is approaching baseline function, not merely mildly improved 3

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Endovascular Thrombectomy

Mechanical thrombectomy with stent retrievers (Solitaire, Trevo) should be performed for patients meeting all criteria: prestroke mRS 0–1, large vessel occlusion (ICA or proximal M1) on CTA, age ≥18 years, NIHSS ≥6, ASPECTS ≥6, and groin puncture possible within 6 hours of symptom onset. 2

• Five randomized trials (MR CLEAN, ESCAPE, SWIFT-PRIME, EXTEND-IA, REVASCAT) demonstrated superior functional outcomes 2
• Selected patients meeting specific imaging criteria may be treated up to 24 hours after onset 2, 1
• Endovascular therapy must not postpone IV alteplase when the patient is eligible for both; deliver sequentially 2
• Apply "drip-and-ship" strategy: give alteplase at primary stroke center and immediately transfer for thrombectomy when large vessel occlusion is suspected 1

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Antiplatelet Therapy

Start aspirin 325 mg within 24–48 hours after stroke onset, but wait 24 hours after alteplase and obtain repeat head CT to exclude hemorrhage before starting aspirin. 2

• Aspirin's primary benefit is reduction of early recurrent stroke, not mitigation of initial injury 2
• Aspirin must not be administered within 24 hours of alteplase because it raises hemorrhage risk 2
• Aspirin is not a substitute for IV alteplase in patients who meet thrombolysis criteria 2
• Clopidogrel alone or combined with aspirin is not recommended for acute ischemic stroke 2

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Anticoagulation in the Acute Phase

Full-dose unfractionated heparin or low-molecular-weight heparin should not be used for acute ischemic stroke; they do not improve outcomes and increase hemorrhage risk. 2

• Emergency anticoagulation does not lower the risk of early recurrent stroke, even in cardioembolic sources 2
• Anticoagulation does not prevent early neurological worsening 2
• Most randomized trials have failed to demonstrate benefit on functional outcomes 2

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Stroke Unit Care and Monitoring

Admit to dedicated stroke unit with monitored beds for at least 24 hours; stroke unit care reduces mortality and morbidity comparably to the effects of alteplase itself. 2

• Maintain oxygen saturation ≥92% using pulse oximetry; provide supplemental oxygen only when saturation falls below 94% 2
• Check core temperature every 4 hours for first 48 hours and treat fever promptly (target ≤37.5°C); fever reduction decreases neurological damage 2
• Begin frequent brief mobilization (sitting, standing, brief ambulation) within 24 hours if no contraindications 2
• Assess swallowing before any oral intake to prevent aspiration 2

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Venous Thromboembolism Prophylaxis

Start intermittent pneumatic compression devices within 24 hours for immobile patients; when drug prophylaxis is indicated, use prophylactic-dose low-molecular-weight heparin rather than unfractionated heparin. 2

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Secondary Prevention (Long-Term)

Antiplatelet Therapy

For ongoing secondary prevention, prescribe clopidogrel 75 mg daily or aspirin 75–100 mg + extended-release dipyridamole (25 mg/200 mg twice daily), which are favored over aspirin alone for reducing recurrent stroke risk. 2

• Alternative options include aspirin 75–100 mg daily or cilostazol 100 mg twice daily 2
• Do not combine clopidogrel with aspirin for chronic secondary prevention 2

Anticoagulation for Atrial Fibrillation

In patients with prior stroke/TIA and atrial fibrillation, prescribe oral anticoagulation (warfarin or direct oral anticoagulant) rather than no therapy, aspirin alone, or aspirin + clopidogrel. 2

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Common Pitfalls to Avoid

• Never aggressively lower BP in acute stroke unless giving thrombolytics or BP >220/120 mmHg; permissive hypertension maintains penumbral perfusion 2
• Do not delay IV alteplase to obtain advanced imaging (CTA, MRI perfusion) in patients within the 3–4.5 hour window 2, 3
• Do not give aspirin as adjunctive therapy with alteplase 2
• Do not delay alteplase for "minor" or improving symptoms unless the patient is approaching baseline function 2, 3
• Never postpone transfer to obtain imaging at a non-CT facility; rapid transport supersedes any on-site intervention without imaging 1
• Do not withhold transfer for "mild" symptoms; large vessel occlusions can present with fluctuating deficits 1
• Do not assume patients beyond 4.5 hours are ineligible; endovascular treatment may be offered up to 24 hours with appropriate imaging selection 1

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Time-Dependent Outcomes

• Treatment within 90 minutes of onset is most likely to result in favorable outcomes 2
• Every 30-minute delay in reperfusion reduces the probability of favorable outcome by 10.6% 2
• Endovascular thrombectomy is highly effective within 6 hours for most large vessel occlusions and remains beneficial up to 24 hours in selected patients 2, 1