What is the immediate treatment for acute ischemic infarct (stroke)?

Immediate Treatment for Acute Ischemic Stroke

Intravenous alteplase (rtPA) at 0.9 mg/kg (maximum 90 mg) is the cornerstone of immediate treatment for acute ischemic stroke when administered within 3-4.5 hours of symptom onset, followed by aspirin 160-325 mg within 48 hours for patients not receiving thrombolysis. 1

Time-Critical Reperfusion Therapy

The treatment approach is fundamentally determined by time from symptom onset:

Within 3 Hours of Symptom Onset

• Administer IV rtPA (0.9 mg/kg, maximum 90 mg) immediately after excluding hemorrhage on brain imaging 1
• 10% given as bolus over 1 minute, remaining 90% infused over 60 minutes 1
• This represents Grade 1A evidence with the strongest benefit 1

Between 3-4.5 Hours of Symptom Onset

• IV rtPA is still recommended but with slightly more selective patient criteria 1, 2
• Evidence is Grade 2C, but treatment remains beneficial 1
• Earlier treatment within this window yields better outcomes 1

Beyond 4.5 Hours

• IV rtPA is contraindicated and should not be administered 1
• Consider mechanical thrombectomy for large vessel occlusion within 6-24 hours based on advanced imaging criteria 2

Critical Pre-Treatment Steps

Before administering rtPA, the following must be completed rapidly:

Immediate Assessment (Target: <60 minutes door-to-needle)

• Confirm exact time patient was last known normal - this is "time zero," not when symptoms were discovered 3
• Obtain non-contrast CT or MRI immediately to exclude hemorrhage 2, 3
• Assess stroke severity using NIHSS scale 2
• Check fingerstick glucose immediately - hypoglycemia (<60 mg/dL) is a stroke mimic requiring IV glucose 3

Blood Pressure Management Before rtPA

• If systolic BP >185 mmHg or diastolic >110 mmHg, blood pressure must be lowered before rtPA administration 1
• Use labetalol 10-20 mg IV over 1-2 minutes, may repeat once 1
• Alternative: nicardipine drip 5 mg/h, titrate up by 2.5 mg/h every 5-15 minutes (maximum 15 mg/h) 1
• If blood pressure cannot be controlled to <185/110 mmHg, do not administer rtPA 1

Dosing Accuracy

• Calculate dose based on actual measured weight, not estimated weight 4
• Estimation errors occur in 22.7% of cases and increase bleeding risk 4
• Each 10% increase in dose above 0.90 mg/kg increases intracerebral hemorrhage risk (OR 3.10) 4

Antiplatelet Therapy

For Patients NOT Receiving rtPA

• Administer aspirin 160-325 mg within 48 hours of symptom onset 1
• This is Grade 1A evidence for reducing early recurrent stroke 1

For Patients Receiving rtPA

• Do not administer aspirin or any antiplatelet/anticoagulant agents for 24 hours after rtPA 1
• This restriction is critical to minimize bleeding complications 1

Supportive Care During Acute Phase

Airway and Oxygenation

• Provide supplemental oxygen if saturation <94% 2, 3
• Intubate if airway is compromised or ventilation inadequate 2

Blood Pressure Management (Non-Thrombolysis Candidates)

• Avoid lowering blood pressure unless systolic >220 mmHg or diastolic >120 mmHg 1, 2
• Permissive hypertension improves cerebral perfusion in acute stroke 2
• Exception: treat if acute MI, aortic dissection, acute renal failure, pulmonary edema, or eclampsia present 2

Positioning

• Keep head flat (not elevated) if patient is hypotensive (systolic <120 mmHg) to improve cerebral perfusion 3

VTE Prophylaxis

• For patients with restricted mobility, use prophylactic-dose subcutaneous LMWH or intermittent pneumatic compression 1
• Prefer LMWH over unfractionated heparin (Grade 2B) 1

Critical Contraindications to rtPA

Do not administer rtPA if:

• Symptom onset >4.5 hours 1
• Evidence of hemorrhage on brain imaging 1
• Blood pressure cannot be controlled to <185/110 mmHg 1
• Recent stroke or head trauma within 3 months 1
• Recent myocardial infarction within 3 months 1

Monitoring After rtPA Administration

• Check blood pressure every 15 minutes for 2 hours, then every 30 minutes for 6 hours, then hourly for 16 hours 1
• Maintain systolic BP <180 mmHg and diastolic <105 mmHg post-treatment 1
• Monitor for signs of intracranial hemorrhage (occurs in 3.3-7% of patients) 5, 6

Common Pitfalls to Avoid

• Using estimated rather than measured weight increases dosing errors and bleeding risk 4
• Delaying treatment for written consent - verbal consent with documentation is acceptable; in emergencies without available surrogate, proceed with treatment 1
• Administering anticoagulants or antiplatelets within 24 hours of rtPA dramatically increases bleeding risk 1
• Treating patients beyond 4.5 hours with IV rtPA - this is contraindicated and increases harm 1

Anticoagulation Is NOT Recommended

Urgent anticoagulation with heparin, LMWH, or heparinoids is not recommended for acute ischemic stroke 1

• Does not improve neurological outcomes or prevent early recurrent stroke (Grade A) 1
• Increases risk of symptomatic intracerebral hemorrhage, especially in moderate-to-severe strokes 1
• No benefit demonstrated even in large-vessel atherothrombosis or high embolic risk patients 1