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NIH Stroke Scale (NIHSS)
Quantitative measure of stroke-related neurological deficit — 11 items, score 0–42
Level of Consciousness
Motor
Language, Speech & Attention
—
NIHSS Score / 42
NIHSS Interpretation
| Score | Severity | Notes |
|---|---|---|
| 0 | No stroke symptoms | Baseline normal |
| 1–4 | Minor stroke | Consider tPA if in window |
| 5–15 | Moderate | tPA eligible (if criteria met) |
| 16–20 | Moderate-severe | tPA/thrombectomy consideration |
| 21–42 | Severe | Aggressive intervention warranted |
Total = sum of all 11 items (0–42)
IV tPA window: ≤4.5 hours from symptom onset (AHA/ASA 2019)
Mechanical thrombectomy: NIHSS ≥6, up to 24h with imaging selection
IV tPA window: ≤4.5 hours from symptom onset (AHA/ASA 2019)
Mechanical thrombectomy: NIHSS ≥6, up to 24h with imaging selection
Thrombolysis Note: NIHSS is one component of tPA eligibility. Consider: time of onset, CT findings, BP, coagulation, age, and contraindications. NIHSS <4 (minor stroke) — weigh risks carefully. NIHSS >22 — high haemorrhage risk.
For clinical decision support only. Not a substitute for professional medical judgment.
