Stroke

BE-FAST – Stroke Recognition

ABC → Stroke? (BE FAST) → LKW Time? & GRBS → CT → Vessel? → Reperfuse

Stroke is a clinical diagnosis; CT initially excludes haemorrhage.

Cincinnati (FAST) pre-hospital stroke scale: 

• If one component is present -> 72% chance of an acute stroke

• If three components are present -> 85% chance of an acute stroke

• It is not good for assessing posterior stroke

Proportion of missed stroke patients reduced to 4.4% by assessing 1. Balance, & 2. Eye changes => BE-FAST

Stroke algorithm 

1. Initial impression

2. (0-30 seconds) ABCDE (only life-threatening problems)- Resuscitation precedes diagnosis

3. (30-60 seconds) Suspect stroke (perform a Rapid stroke screen; BE-FAST) - Stroke syndrome localisation

4. (within 2 minutes) Activate Stroke Alert

5. Determine Last Known Well (LKW) time

6. Rapid glucose

7. NIHSS

8. CT ± CTA (if thrombectomy candidate,)

9. Decision for reperfusion

10. BP control if >185/110 mmHg.

11. Investigations: ECG, two IV access, CBC, PTINR, Creatinine (for CTA), Pregnancy test

12. Thrombolysis/thrombectomy decision (consent)

13. ICU/Stroke unit admission

Exclusion criteria (Thrombolysis):

1. Haemorrhage; IC bleed or previous IC bleed

2. BP >185/110 despite treatment

3. Surgery: major surgery < 2 weeks, head trauma < 3months

4. Bleeding risk: INR > 1.7, platelets < 1 lakh, LMWH within 24 hours, DOAC < 48 hours, active internal bleeding

Drugs:

1. BP: Labetalol 10–20 mg IV or Nicardipine infusion

2. Thrombolysis : 

   1. • Alteplase (rtPA) 0.9 mg/kg (maximum 90 mg) - 10% as IV bolus over 1 minute + 90% infusion over 60 minutes

      • Tenecteplase 0.25 mg/kg IV bolus (Maximum 25 mg)

Monitoring:

During infusion

1. Neuro assessment

2. BP every 15 min

3. Watch for headache / Vomiting / Sudden deterioration / Angioedema

After thrombolysis

1. BP <180/105

2. No aspirin/anticoagulant/IM injections/invasive procedures for 24 hours

3. Repeat CT/MRI at 24 hours before antiplatelets

BP Monitoring:

First 2 hours: BP & neurological checks every 15 minutes

Next 6 hours: BP & neurological checks every 30 minutes

8–24 hours: BP & neurological checks every 1 hour

BP goal throughout first 24 hours: <180/105 mmHg

Stroke mimics:

1. Hypoglycemia

2. Seizure (Todd's paralysis)

3. Migraine

4. Bell's palsy (isolated facial weakness)

5. Functional disorder (inconsistent examination)

6. Brain tumour (progressive symptoms)

7. Encephalitis (fever, confusion)

8. Drug intoxication (history/toxidrome)

Six Core Presentations:

1. Left MCA Stroke (Dominant Hemisphere)

• Aphasia

• Right facial weakness

• Right arm > leg weakness

• Right sensory loss

• Right homonymous hemianopia

2. Right MCA Stroke (Nondominant Hemisphere)

• Left hemiplegia

• Left neglect

• Left sensory loss

• Left visual field defect

• Gaze preference to the right

Detect neglect

Identify cortical signs

Suspect large vessel occlusion

Extinction (visual/auditory/tactile): most commonly due to a non-dominant (usually right) parietal lobe stroke

3. Brainstem / Posterior Circulation Stroke

• Vertigo

• Diplopia

• Dysarthria

• Dysphagia

• Ataxia

• Crossed neurological findings

• Altered consciousness (sometimes)

Posterior stroke is frequently missed

Normal CT does not exclude it

CTA is often critical

4. Cerebellar Stroke

• Sudden severe vertigo

• Vomiting

• Inability to walk

• Dysmetria

• Nystagmus

• Minimal weakness.

Differentiate from peripheral vestibular disease

Recognise patients at risk of brainstem compression

5. Intracerebral Haemorrhage

• Severe headache

• Vomiting

• Progressive reduction in GCS

• Focal neurological deficit

• Markedly elevated blood pressure

Immediate CT diagnosis

BP control

Neurosurgical consultation

6. Stroke Mimic

• Hypoglycemia

• Postictal (Todd's) paralysis

• Migraine

• Bell's palsy

• Functional neurological disorder

Lacunar Infarct:

A lacunar stroke is a small ischemic infarction caused by occlusion of a single deep penetrating artery. These arteries arise from major cerebral vessels but supply the deep brain structures (Internal capsule, Basal ganglia, Thalamus, Corona radiata, or Pons), not the cortex.

How to recognise: Dense weakness or sensory loss without cortical signs.

Because the cerebral cortex is spared, cortical signs are absent, such as:

• Aphasia

• Neglect

• Gaze deviation

• Visual field defects

• Seizures

Classical syndromes

1. Pure Motor Stroke (Most common); Contralateral face, arm, and leg weakness, No sensory loss, No aphasia, no neglect

2. Pure Sensory Stroke: Contralateral numbness, Face, arm, and leg affected, and Normal power

3. Sensorimotor Stroke (site: Thalamocapsular region); Contralateral weakness, Contralateral sensory loss, no cortical signs

4. Ataxic Hemiparesis (Site: Pons or internal capsule); Ipsilateral limb ataxia with contralateral weakness, Leg often more affected than arm

5. Dysarthria–Clumsy Hand Syndrome (Site: Basis pontis or internal capsule); Slurred speech, Clumsy hand, Mild facial weakness, Fine motor impairment

NIH Stroke Scale:

11. Extinction & Inattention. (Extinction is an early or mild manifestation of neglect.)

• Extinction -> misses the affected side only during simultaneous bilateral stimulation. 

• Inattention -> ignores the affected side even during routine activities

A patient with a right middle cerebral artery (MCA) stroke may:

Have left-sided weakness.

Have left hemisensory loss.

Have left homonymous hemianopia.

Ignore the left side despite intact primary sensation.

Show left-sided extinction on simultaneous stimulation.

BE-FAST & HINTS Examination:

• BEFAST is a stroke recognition tool, applied to any patient with possible stroke. It screens both anterior and posterior strokes

• HINTS is a diagnostic examination, applied only to AVS (Acute vestibular syndrome). It distinguishes central stroke from peripheral vestibular disease

Acute Vestibular Syndrome, defined by:

1. Acute continuous vertigo or dizziness (lasting >24 hours)

2. Spontaneous nystagmus

3. Nausea/vomiting

4. Gait unsteadiness

5. Symptoms are present at the time of examination

Do not use HINTS for:

• Brief episodic vertigo (e.g., BPPV)

• Patients without nystagmus

• Patients with obvious focal neurological deficits (they already need stroke workup)

HINTS Examination:

1. Head Impulse Test: Ask the patient to look at your nose. Quickly rotate the head about 15–20° to each side.

• Peripheral lesion (Vestibular neuritis) -> Corrective saccade present (Abnormal Head Impulse) => Favors a peripheral cause

• Central lesion (Stroke) -> Eyes remain fixed on the target (Normal Head Impulse) => Concerning for stroke

Mnemonic: Normal head impulse = Not Normal (think stroke).

2. Nystagmus: Observe gaze in primary position and on looking left and right.

• Peripheral; Unidirectional, Horizontal with a torsional component, Follows Alexander's law

• Central; Direction-changing gaze-evoked nystagmus

Pure vertical nystagmus

Pure torsional nystagmus

3. Test of Skew: Cover one eye, then rapidly uncover it while covering the other (alternate cover test).

• Vertical corrective movement indicates skew deviation.

• Skew deviation strongly suggests: Brainstem stroke/Cerebellar stroke

HINTS+" adds: New unilateral hearing loss

Sudden hearing loss with vertigo raises suspicion for an AICA infarction, as the inner ear is supplied by the labyrinthine artery, commonly a branch of the anterior inferior cerebellar artery

Patient with vertigo approach

Step 1: Is it continuous or episodic?

• Episodic → Consider BPPV, vestibular migraine, etc.

• Continuous → Acute Vestibular Syndrome

Step 2: Are there obvious neurological deficits?

Limb weakness/Dysarthria/Diplopia/Ataxia/Decreased consciousness

If yes, activate the stroke pathway. HINTS is unnecessary.

Step 3: Isolated Acute Vestibular Syndrome?

If the patient has isolated continuous vertigo with spontaneous nystagmus and no obvious focal deficits, HINTS (performed by a trained examiner) can help distinguish vestibular neuritis from posterior circulation stroke.