• Neurology · Emergency Medicine
Acute Ischemic Stroke
FAST Criteria · NIHSS · tPA Eligibility · Thrombectomy Criteria · BP Management
🧠 FAST Recognition & NIHSS Severity
F
Face drooping — Ask to smile. Is one side drooping?
A
Arm weakness — Raise both arms. Does one drift down?
S
Speech difficulty — Slurred, garbled, or unable to speak?
T
Time — Note exact symptom onset. Call code stroke NOW.
NIHSS Severity Classification
0–4
Minor stroke
5–15
Moderate
16–20
Moderately severe
21–42
Severe stroke
⏱️ Critical Time Targets (AHA/ASA 2019)
<10 min
Door to physician
<25 min
Door to CT scan
<45 min
CT interpretation
<60 min
Door to needle (tPA)
4.5 h
tPA window (onset)
6–24 h
Thrombectomy window
3–4.5 h
Extended tPA (select pts)
24 h
Dual antiplatelet (minor)
✅ tPA Eligibility Criteria (0–3h window)
Age ≥18 years
Diagnosis of acute ischemic stroke with measurable deficit
Onset (or last known well) <3 hours (3–4.5 h in selected patients)
CT: no hemorrhage, no large established infarct (<1/3 MCA territory)
BP <185/110 mmHg at time of treatment
No hypoglycemia (glucose >50 mg/dL)
Alteplase dose: 0.9 mg/kg IV (max 90 mg); 10% as bolus, rest over 60 min
🚫 tPA Absolute Contraindications
●Intracranial hemorrhage on CT (any type)
●Prior intracranial hemorrhage (lifetime)
●Subarachnoid hemorrhage (presenting symptoms)
●Active internal bleeding (excluding menses)
●Platelet count <100,000/mm³
●Heparin within 48h with elevated aPTT; INR >1.7
●Recent (3 months) intracranial/spinal surgery or serious head trauma
●Blood glucose <50 mg/dL or >400 mg/dL
🔧 Mechanical Thrombectomy Criteria
NIHSS ≥6 with large vessel occlusion (ICA, M1, M2)
ASPECTS ≥6 on CT (within 6 hours)
Window: 0–6 h from onset (Class I)
Extended window (6–24 h): DAWN/DEFUSE-3 criteria — clinical-imaging mismatch, selected patients
mRS ≤2 pre-stroke (functional independence)
Thrombectomy + tPA if eligible (bridging therapy)
Target: TICI 2b/3 reperfusion (≥50% territory)
📊 Blood Pressure Management
Pre-tPA: Must be <185/110 mmHg. Use labetalol or nicardipine.
During/after tPA: Maintain <180/105 mmHg for 24h
No reperfusion therapy: Allow permissive HTN up to 220/120 mmHg (unless other organ damage)
Post-thrombectomy: SBP target <180 mmHg
Hypotension: Actively treated — maintain SBP ≥140 mmHg (avoid cerebral hypoperfusion)
Resume antihypertensives at 24h if neurologically stable
CCM Notes · FOAMed · Critical Care Clinical Reference
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Based on AHA/ASA Stroke Guidelines 2019 / 2023 Update
Educational use only