End
NIH Stroke Scale (NIHSS)
Quantifies the severity of an ischemic stroke in the acute setting. Used to predict clinical outcomes and guide thrombolytic therapy decisions.
1a. Level of Consciousness (LOC)
Score strictly what you see.
1b. LOC Questions
Ask the patient’s age and current month. Must be exact.
1c. LOC Commands
Ask patient to open/close eyes and grip/release non-paretic hand.
2. Best Gaze
Only horizontal eye movements are tested.
3. Visual
Test visual fields by confrontation.
4. Facial Palsy
Ask patient to show teeth, raise eyebrows, and close eyes tightly.
5a. Motor – Left Arm
Extend arm 90° (sitting) or 45° (supine) for 10 seconds.
5b. Motor – Right Arm
Extend arm 90° (sitting) or 45° (supine) for 10 seconds.
6a. Motor – Left Leg
Raise leg 30° (supine) for 5 seconds.
6b. Motor – Right Leg
Raise leg 30° (supine) for 5 seconds.
7. Limb Ataxia
Finger-nose-finger and heel-shin tests on both sides.
8. Sensory
Pinprick testing for sensory loss.
9. Best Language
Describe a picture, name items, read sentences.
10. Dysarthria
Evaluate clarity of speech (read words).
11. Extinction and Inattention (Neglect)
Assess spatial and personal neglect.
0
Points
Evaluating…
| Score | Stroke Severity | Clinical Interpretation |
|---|---|---|
| 0 | No Stroke Symptoms | Normal neurological exam. Keep mimics in mind. |
| 1 – 4 | Minor Stroke | Highly likely to have favorable outcomes. 75% of pts with score ≤4 are functionally independent at 1 year. |
| 5 – 15 | Moderate Stroke | Consider tPA and aggressive management. Transfer to stroke center. |
| 16 – 20 | Moderate to Severe | Significant deficits. High likelihood of rehab or nursing home placement. |
| 21 – 42 | Severe Stroke | High risk of hemorrhagic conversion with tPA (>17% rate if NIHSS >20). Severe long-term morbidity. |
1
Strict Rule Application: Score what you see, not what you think. Score the first response, not the best response (except Item 9 – Best Language). Don’t coach the patient.
2
Posterior Circulation Strokes: A patient with even a large territory posterior circulation stroke syndrome may still have a low or normal NIHSS, highlighting an important limitation of the scale.
3
High Scores & tPA: Many guidelines warn that administering tPA in patients with a high NIHSS score (>22) is associated with increased risk of hemorrhagic conversion. However, these patients are also the most severely debilitated.
4
Interrater Reliability: Some components (facial movement, limb ataxia, neglect, LOC) have lower interrater reliability. Up to 1 in 3 initial scores have meaningful differences between clinicians.
