NIHSS (National Institute of Health Stroke Scale)
Standardized 15-item bedside examination, measures severity of neurological deficits in acute stroke. Score range 0-42, higher is worse. Allows succinct communication between ER, telestroke, ±stroke neurologist.
NIHSS is used to:
Communicate clearly / succinctly between ER, telestroke, stroke neurologist, etc.
Track changes over time (≥4 point change is concerning for neurological deterioration).
Support decisions about thrombolysis and EVT.
Limitations:
Measures deficits not disability. Low score may still be disabling (ex. Weakness of dominant hand, occupation-specific tasks).
Does not assess distal motor function. ex. dominant hand may be completely weak, but the arm is strong enough to not get a score.
Weighted towards anterior circulation and left hemisphere. ex. 7 points come from language (left hemisphere) vs 2 for neglect (similar territory right hemisphere).
Misses portions of posterior circulation. Cerebellar and basilar strokes may be severe and life-threatening with NIHSS in the low-single digits.
Reliability can vary by item, by examiner, and by patient factors (ex. decreased LOC, language barrier, etc).
Not a sensitive LVO screen. Thought higher scores raise suspicion for LVO, lower score does not exclude an LVO.
NIHSS Items (total 0-42)
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0-3: LOC (alert, minor stimulation, repeated stimulation, move to pain, unresponsive)
0-2: LOC Questions (month, age)
0-2: LOC Commands (open/close eyes, grip/release hand) -
0: Normal
1: Partial gaze palsy
2: Forced gaze palsy (cannot be overcome)
-
0: No visual loss
1: Partial hemianopsia
2: Complete hemianopsia
3: Bilateral hemianopsia
-
0: Normal
1: Minor paralysis
2: Partial paralysis
3: Complete unilateral paralysis
Bilateral paralysis also scores 3 points, though just a note to consider alternate diagnoses in this case as well!
-
Score for each left side (5A) and right side (5B).
0: No drift
1: Drift but does not hit the bed
2: Drift, hits the bed
3: No effort against gravity (immediately hits the bed)
4: No movement.
Amputation scores a 0 / UN.
-
Score for each left side (6A) and right side (6B).
0: No drift
1: Drift but does not hit the bed
2: Drift, hits the bed
3: No effort against gravity (immediately hits the bed)
4: No movement.
Amputation scores a 0 / UN.
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Finger-nose & heel-shin testing.
0: Normal.
1: Ataxia in 1 limb.
2: Ataxia in 2 limbs.
Do not score amputation, or paralysis (unless ataxia is out of keeping to level of weakness).
-
0: Normal.
1: Mild-moderate (can sense touch, but it is reduced)
2: Complete loss, cannot send being touched.
Also score a 2 for a patient who is plegic or unresponsive and does not respond to noxious stimulus (ex. grimace to DPS)
-
Use standardized NIHSS scene, naming images, and sentences (scorecards, or googleable).
0: Normal.
1: Mild-moderate aphasia. Some changes without limitation
2: Severe aphasia. Cannot identify speech
3: Mute / global aphasia. No usable speech or auditory comprehension.
Score coma / unresponsiveness as 3.
-
0: Normal.
1: Mild-moderate dysarthria. Slurred words but can be understood.
2: Severe dysarthria. Unintelligible slurring.
If mute, score as 2.
If cannot test (ex. patient intubated) score as a 0. -
0: Normal.
1: Visual, tactile, auditory, spatial, personal inattention. Extinction to bilateral simultaneous stimulation (cannot sense touch in 1 if 2 limbs are touched at the same time; cannot count fingers in both hemifields at the same time).
2: Profound semi-inattention (ex. cannot recognize own hand), or extinction to >1 modality.
Neurology phone call checklist
Information to have on-hand when you’re calling neuro for advice.
Pertinent history:
Last seen well.
Any recent major health changes, procedures, systemic symptoms.
Relevant history: anticoagulation, prior stroke or seizure, immunosuppression.
Modified Rankin Scale (MRS) or level of baseline disability including ambulation and independence.
Examination:
Current vitals including BP.
Weight.
Approximate NIHSS.
Even if you can’t do the NIHSS, if you tell us the patient is severely disabled and can give a good enough description to know that it is localizing, this can be extremely helpful and we will walk you through the rest.
Investigations:
Consider mimics: glucose, electrolytes.
Eligibility for lysis: platelets, INR, PTT. Anti-Xa if relevant / available.
CT images if available.
Transport considerations: anticipated transport duration, stability for transport.
Anticoagulation reversal in patients with ICH
Generally call thrombosis (or hematology) on call if available. Neurology can also help you out if you cannot reach / don’t have access to thrombosis.
Warfarin: PCC + IV vitamin K.
Apixaban, rivaroxaban, edoxaban: 4F-PCC per protocol.
Dabigatran: idarucizumab if available. 4F-PCC if not.
For any anticoagulants taken recently (within 2-4 hours before presentation) consider activated charcoal. Discuss with thrombosis / neuro.
Eligibility and Contraindications for IV thrombolysis and EVT
(Based on Canadian Stroke Best Practice Recommendations, reviewed 24 October, 2026)
IV thrombolysis eligibility (TNK & tPA)
Last known well <4.5 hours.
Age ≥ 18 (on label - thrombolysis can be used in paediatric patients).
Disabling deficit - loose NIHSS cutoff is 4, although disability can occur with NIHSS ≤4.
Non-contrast CT demonstrating no hemorrhage.
NOTE: You do not need to wait for routine labs unless you expect a coagulopathy or thrombocytopenia. POC glucose is the main required test.
Absolute contraindications: active intracerebral hemorrhage. BP > 185/105 (can lower BP and administer IVT).
Caution for: active major bleeding, recent stroke (within 3 months), recent surgery (within 14 days), diagnostic uncertainty or concern for mimics, anticoagulation, early signs of extensive infarction on imaging (>1/3 MCA territory).
Endovascular therapy (EVT) / thrombectomy
Independent at baseline (mRS ≤2).
Disabling deficit (NIHSS >5 loose cutoff).
Last known well ≤24 hours ago
0-6 hours: standard window.
6-24 hours: extended window in specific patients, generally requires CT perfusion.
Accessible large vessel occlusion (intracranial ICA, M1, basilar).
Small infarct core (ASPECTS ≥6) - can consider in larger established infarcts in certain cases, especially younger patients.
Does NOT require the patient to be eligible for IVT.
What is going on with these expanded windows??? Certain imaging modalities opens up the treatment window significantly, especially for patients with LVO for EVT. Even if you think that the person is outside the window but the stroke is severe, consider speaking with neurology.
Secondary Stroke Prevention Guidelines
https://www.strokebestpractices.ca/recommendations/secondary-prevention-of-stroke
Blood pressure:
Target <140/90 in patients without significant comorbidities.
Consider lower target <130/80 in patients with lacunar stroke, comorbid T2DM, hx ICH.
Lipids:
Always consider a low-dose statin for non-cardioembolic ischemic stroke or TIA (not for ICH).
LDL target <1.8 mmol/L.
Diabetes:
HbA1c target ≤7% for most patients. Older patients may have a more lenient target if concern for hypoglycaemia.
Lifestyle:
Smoking cessation.
Sodium ≤2000 mg/d. Medeterranean style or DASH diet.
≥150 minutes per week moderate intensity exercise, with strength / resistance training if possible.
Avoid heavy alcohol use ≤2 drinks per week per new Canadian guidelines.
Other:
Consider gynaecology referral for hormonal therapy (MHT, gender affirming hormones, OCP).
