What is the management of ischemic stroke, particularly in terms of timing and treatment?

Management of Ischemic Stroke: Time-Critical Interventions

Rapid intervention is crucial in ischemic stroke management, with intravenous thrombolysis within 4.5 hours and endovascular thrombectomy within 6-24 hours being the cornerstone treatments for eligible patients. 1, 2

Initial Assessment and Immediate Management

• Time-Critical Actions:
  • Rapid airway assessment and support for patients with depressed consciousness
  • Supplemental oxygen only for hypoxic patients
  • Immediate blood glucose measurement and correction of hypoglycemia
  • Cardiac monitoring to detect atrial fibrillation and life-threatening arrhythmias
  • Cautious management of hypertension (avoid treatment unless BP >220/120 mmHg)

Reperfusion Therapies

Intravenous Thrombolysis

• Timing: Within 4.5 hours of symptom onset
• Agent: Recombinant tissue plasminogen activator (rtPA)
• Blood Pressure Target: <185/110 mmHg before administration
• Efficacy: Improves likelihood of minimal/no disability from 26% to 39% when given within 3 hours 1, 3

Endovascular Therapy (EVT)

• Timing:
  • Within 6 hours for standard cases
  • Extended window of 6-24 hours for selected patients with salvageable tissue
• Indication: Large vessel occlusion (LVO)
• Technique: Combined approach using stent-retrievers and aspiration for fastest reperfusion
• Efficacy: Increases functional independence from 26.5% to 46% when performed within 6 hours 2, 3

Critical Time Considerations

• Every 30-minute delay in recanalization decreases good functional outcome chance by 8-14% 2
• Avoid time-consuming imaging methods and overly selective treatment criteria
• Rapid patient transfer systems are essential - EMS transport can halve pre-hospital time 4

Post-Acute Management

First 24-48 Hours

• Admit to dedicated stroke unit or neurocritical care unit
• Monitor for neurological deterioration (occurs in ~25% of patients)
• Initiate aspirin (325mg initially, then 81-325mg daily) within 24-48 hours after stroke onset
  • Delay 24+ hours if IV thrombolysis was administered 1
• Implement DVT prophylaxis for patients with limited mobility
• Monitor and treat fever (>38°C)

Antithrombotic Therapy

• Non-cardioembolic stroke:
  • Dual antiplatelet therapy (aspirin + clopidogrel) for 21-90 days for minor strokes and high-risk TIAs
  • Then transition to single antiplatelet therapy 1, 3
• Cardioembolic stroke (e.g., atrial fibrillation):
  • Oral anticoagulation with direct oral anticoagulants (preferred) or warfarin (target INR 2.0-3.0) 1

Surgical Interventions

• Carotid endarterectomy: For symptomatic carotid stenosis (70-99%)
• Surgical decompression: Consider for large cerebellar infarctions causing brainstem compression
• Hemicraniectomy: Within 48 hours for extensive hemispheric infarcts in selected patients (18-60 years) 1

Rehabilitation and Secondary Prevention

• Begin rehabilitation as early as possible (within 24-48 hours for stable patients)
• Implement aggressive management of modifiable risk factors:
  • Hypertension (target <140/90 mmHg)
  • Diabetes (target fasting glucose <126 mg/dL)
  • Hyperlipidemia (target LDL <100 mg/dL)
  • Smoking cessation

Common Pitfalls to Avoid

1. Delayed recognition and treatment - "Time is brain" - establish rapid triage protocols
2. Excessive imaging - Avoid time-consuming protocols that delay treatment
3. Aggressive BP lowering - Avoid precipitous reductions that may worsen ischemia
4. Sublingual nifedipine - Avoid due to risk of rapid, uncontrolled BP reduction
5. Patient overselection - Overly restrictive criteria may exclude patients who could benefit
6. Inadequate post-thrombolysis monitoring - Close observation needed for hemorrhagic complications

The management of ischemic stroke requires a coordinated system of care with emphasis on rapid assessment, diagnosis, and treatment to maximize brain tissue salvage and improve patient outcomes.