Neuro Day 2

Stroke + Management, Neurological Assessment

Stroke Definition (aka)

A neurological deficit attributed to acute focal (localised) injury of the CNS by a vascular cause. It is caused by blockage of blood flow or bleeding into the brain. AKA Cerebrovascular Accident

Transient Ischaemic Attack (TIA) (definition, symtpom duration & importance)

A transient episode of neurological dysfunction caused by a focal brain, spinal cord, or retinal ischemia, without acute infarction. Symtpoms typically <1 hr, and is high risk factor for a stroke

TIA Investigation Methods

Carotid doppler US, CT angiography, MR angiography, and investigation for atrial fibrillation.

TIA vs Stroke

A stroke causes permanent brain damage due to a blocked or burst blood vessel, while a transient ischaemic attack (TIA) is a temporary blockage that resolves within 24 hours without lasting damage—but it’s a serious warning sign of a possible future stroke

Ischaemic Stroke Definition (Aka Cerebral Infarction)

A clot blocks blood flow to the brain, restricting oxygen to the brain. Accounts for 85% of all strokes

Thrombus

A clot formed local to the brain.

Embolus

A clot formed elsewhere, carried in the bloodstream, and then lodges.

Most Common Cause of Ischaemic Stroke

Embolism.

Other Common Ischaemic Causes

Large artery atherosclerosis, Small vessel occlusion, Cardioembolism, and Undetermined or other.

Atherosclerosis

the gradual buildup of fatty plaque inside artery walls, causing them to narrow and harden, which restricts blood flow and can lead to heart attacks, strokes, or other serious conditions.

Platelet Activation Role in ischaemic stroke

Contributes to atherosclerosis & thrombus formation by secreting inflammatory substances and becoming active at vulnerable sites.

Thrombus Formation Initiation in ischaemic stroke

Collagen & thrombin initiate thrombus formation at damaged sites.

Cerebral Embolus Action

Blood clot from another region travels to the brain and causes vessel occlusion (e.g., from carotid artery, arch of aorta & heart).

Penumbra

The potentially salvageable brain area that is deoxygenated/partially perfused.

Penumbra Viability

Can be viable for up to 6 hours.

Ischaemic Core

Brain tissue destined to die due to stroke. Without reperfusion, the infarct core gradually expands to include the penumbra.

FAST Acronym

Face, Arms, Speech, Time (Important to salvage tissue).

Haemorrhagic Stroke

Haemorrhage/blood leaks into the brain tissue, caused by the rupture of a blood vessel.

Percentage of Strokes (Haemorrhagic)

Accounts for 15% of all strokes.

Types of haemorrhagic stroke

Intracerebral Haemorrhage & Subarachnoid Haemorrhage

Intracerebral Haemorrhage (ICH)

Bleeding inside the space (~10% of strokes).

Subarachnoid Haemorrhage (SAH)

Bleeding in the subarachnoid space, usually caused by a cerebral aneurysm (~5% of strokes).

Causes of haemorrhagic stroke

Raised BP is leading (including acute hypertension, amphetamines, alcohol, etc.). Cerebral amyloid angiopathy. Vasculr malformations. Bleeding disorders. Trauma. Haemorrhagic transformation

Cerebral Amyloid Angiopathy (CAA)

Deposition of brain amyloid (starch-like protein) in cerebral arteries with ageing, weakening the artery and increasing stroke risk.

Vascular Malformations

Includes Cerebral aneurysm (surgical repair via clipping & coiling).

Causes related to Bleeding Disorders

Anticoagulants, Antiplatelets, Thrombolytic therapy.

Haemorrhagic Transformation

Bleeding secondary to a tumour or infarction.

Important questions in stroke diagnosis

Stroke or not? Type of stroke? Which arterial area? Which specific artery (ischaemic stroke)

Diagnosis Question: Arterial Area

Determine if it is Internal carotid (anterior circulation) or Vertebro-Basilar (posterior circulation).

Disorders Mimicking Stroke

Migraine

Preferred Brain Imaging

MRI (but not always possible).

CT Scan Role

Used first to exclude a haemorrhage; follow-up is necessary to localise ischemic stroke. Haemorrhagic shows immediately on CT, ischaemic not visible for 24 hrs

CTA (Computed Tomography Angiography)

Uses an injection of iodine-rich contrast material to help evaluate blood vessel disease.

Purpose of Secondary Tests

To determine the underlying aetiology for prevention of further strokes.

Secondary Tests of Stroke

CarotidUS of carotid arteries, ECG & Holter monitor, Angiogram of blood vessels, blood tests

Stroke Secondary Test: Carotid US

Checks for carotid stenosis.

Stroke Secondary Test: ECG & Holter monitor

Checks for heart arrhythmias.

Stroke Secondary Test: Angiogram

Checks for possible aneurysms or arteriovenous malformations.

Stroke Secondary Test: Blood tests

Checks for presence of high cholesterol.

Oxford (Bamford) Classification

Predominantly used for ischaemic strokes (1991). TACI. PACI. LACI. POCI.

TACS/I

Total Anterior Circulation Syndrome. Large MCA infarct.

TACS/I Prognosis

Poor functional outcome with high likelihood of death or long term dependency.

TACS/I Criteria

Must have all 3 of the following: Higher Cerebral Dysfunction, Homonymous Hemianopia, Severe motor sensory deficit.

Higher Cerebral Dysfunction (R vs L Hemisphere)

R = Neglect (Spatial neglect). L = Aphasia/dysphasia (Speech difficulties).

Homonymous Hemianopia

Visual field loss on one side.

PACS/I

Partial Anterior Circulation Syndrome). MCA branch occlusion - cortical lesion only.

PACS/I Prognosis

Good prognosis.

PACS/I Criteria

2 out of 3 TACI features (higher cerebral dysfunction, homonymous hemianopia, severe motor sensory deficit) OR Higher dysfunction alone OR Limited motor/sensory deficit (~ 2/3 muscle groups weak).

LACS/I

Lacunar Syndrome. Subcortical stroke due to small vessel disease.

LACS/I Prognosis

Good prognosis.

LACS/I Presentations

Any one of: Pure motor stroke, Pure sensory stroke, Sensori-motor stroke, Ataxic hemiparesis.

LACS/I Exclusion

No higher dysphasia or visuospatial or hemianopia or vertebrobasilar problems.

POCS/I

Posterior Circulation Syndrome. Infarct in posterior cerebral artery, brainstem or cerebellum.

POCS/I Criteria/Diagnosis Examples

Cranial nerve palsy with contralateral motor/sensory deficit, Bilateral motor/sensory deficit, Conjugate eye movement problems, Cerebellar dysfunction, Isolated homonymous hemianopia.

Ischaemic Medical Management includes

Antiplatelet agents, IV thrombolysis, endovascular thrombectomy

Ischaemic Medical Management Goal

Preserve tissue in ischaemic penumbra by restoring blood flow & optimising collateral flow.

Anti-platelet Agents (Ischaemic mngmnt)

Aspirin, heparin (if not receiving reperfusion therapy).

IV Thrombolysis (Ischaemic mngmnt)

Strong recommendation for eligible patients (Tenecteplase or alteplase).

IV Thrombolysis Criteria

strict inclusion/exclusion criteria; administered < 9 hours after symptom onset; provided within a 4.5 hour window.

Endovascular Thrombectomy (EVT)

Surgical removal of clot via angiogram, performed by a neurointerventionist.

Endovascular Thrombectomy Suitability

Suitable for large vessel occlusion (Internal carotid, Proximal middle cerebral artery, Basilar artery).

Endovascular Thrombectomy Timeframe

Should be commenced <24 hours post stroke.

Decompressive Hemicraniectomy

Surgical option for patients <60 yrs with life threatening oedema from an MCA territory infarct. (post ischaemic stroke)

Hemicraniectomy Considerations

May be considered in patients over 60 (carefully) or those with large cerebellar infarct if compromise of brainstem & 4th ventricle.

Haemorrhagic Medical Management

Stabilisation of vital signs, BP & monitoring ICP. Reversal of coagulants, often intubated in ICU if elevated ICP, neurosurgical review warranted

Haemorrhagic BP Management

Bp may be acutely reduced if required.

Medications (Haemorrhagic)

Antihypertensives, anticonvulsants, diuretics.

Reversing Warfarin Effects in Haemorrhagic medical management

Given anticoagulants ASAP (e.g., IV Vit K, prothrombin complex, fresh frozen plasma, recombinant activated factor).

Haemorrhagic Surgical Management

Surgical evacuation or haematoma, decompression surgery (craniectomy) or ventricular drainage for hydrocephalus

Cerebral/Intercranial Aneurysm

A ballooning arising from a weakened area in the wall of a blood vessel in the brain.

Aneurysm Management: Coil Embolisation

Microcatheter delivers coils into the dome until the aneurysm is packed.

Aneurysm Management: Surgical

Surgical clipping. Separates aneurysm from path to brain

Mobile Stroke Unit equipment (MSU)

Built in CT scanner, telemedicine equipment & mobile laboratory.

Mobile Stroke Unit Staffing

Neurologist, nurse, radiographer & paramedics.

Mobile Stroke Unit Function

Able to do quick assessment & administer thrombolysis.

Primary Stroke Impairments (Examples)

Consciousness, orientation, muscle power & endurance, vision, language, temperament, spatial perception, motor planning.

Local Secondary Complications

Due to paralysis: Shoulder subluxation/pain/limitation, Contractures.

Cerebral Secondary Complications

Due to brain damage: Epilepsy, Thalamic pain.

General Secondary Complications

Due to immobility: Bronchopneumonia, Bedsores, Constipation, Deep venous thrombosis (DVT), Pulmonary embolus (PE).

Right CVA (L Hemiplegia/Hemi-anaesthesia)

Associated with L sided problems, hemiplegia, hemi-anaesthesis, homonymous hemianopia, Unilateral neglect, Anosognosia, Constructional apraxia, Unrealistic/uncaring temperament, Poor attention.

Right CVA Safety Risk

Bigger safety risk, falls.

Anosognosia

Severe neglect of the body (associated with R CVA).

Constructional Apraxia

Trouble building or drawing due to brain damage (associated with R CVA).

Left CVA (R Hemiplegia/Hemi-anaesthesia)

Associated with R sided problems, hemiplegia, hemi-anaesthesia homonymous hemianopia, Aphasia/dysphasia (expressive, receptive), Motor apraxia, Dysgraphia/dyscalculia, Realistic/depression/anxious temperament.

Motor Apraxia

Disorder of motor planning (associated with L CVA).

Dysgraphia/Dyscalculia

Number/calculations problem (associated with L CVA

Left side stroke symptoms summary

Left = language & logic

Right side stroke symptoms summary

Right = recognition & risky behaviour

Stroke prognosis is related to:

Individual characteristics of the patient, Severity of their deficits, and the environment the patient is exposed to during the recovery period.

Stroke Prognosis summary

LACI > POCI > PACI > TACI

Relationship between Stroke Size and Outcome

Larger stroke leads to poorer outcomes. TACI outcomes are worse than PACI. LACI generally has best prognosis

Predictors of Poor Recovery

Prior stroke, Severe stroke (particularly with severe motor loss), Prolonged periods of unconsciousness, Urinary incontinence >1 week, Cognitive deficits, Presence of unilateral spatial neglect (R hemisphere), Older age, Presence of comorbidities, Poor PLOF , Depression.

Predictors of Future Mobility

Sitting unsupported and Sit-to-stand are key milestones and best predictors.

Factors Associated with Slower Independent Walking Recovery

Older age, Diabetes, Severe stroke, Haemorrhagic stroke, R hemisphere stroke.

Spontaneous Recovery

Restitution of non-infarcted penumbral areas and Resolution of diaschisis.

Neuroplasticity

Anatomic & functional reorganisation of neural pathways.

Behavioural Compensation

Adaptations that enable compensation for impairments (e.g., circumduction leg to compensate for loss of dorsiflexion).

Acute Recovery Phase

2 weeks post-stroke.

Early Sub-Acute Recovery Phase

2–12 weeks post-stroke.

Late Sub-Acute Recovery Phase

12–24 weeks post-stroke.