STROKE & TIA Flashcards
What is a stroke?
A sudden onset of focal or global neurological deficit of presumed vascular aetiology lasting >24 hours or leading to death
What is a TIA?
a transient (less than 24 hours) neurological dysfunction caused by focal brain, spinal cord, or retinal ischemia, without evidence of acute infarction
Majority resolve within 1 hour
What is a brain attack?
A deficit that is still present when you assess but not yet at 24 hours duration
I.e. you dont know if its a stroke or TIA
Stroke epidemiology?
100,000 strokes every year in the UK
1.3 million people living with a stroke in the UK
A leading cause of death and disability - causes 38,000 deaths in the UK each year
Occurring at younger age now - over 1/3rd of strokes occur in adults 40-69
Non-modifiable risk factors for stroke?
Age - older
Gender - male
Race
FHx
Modifiable risk factors for stroke?
Hypertension
Diabetes
AF
Hyperlipidaemia
Smoking
Obesity
Other established cardiovascular diseases
Other medical conditions: migraine, SCD, haemophilia, hypercoagulable disorders, CKS, ehlers-danlos, Marfan syndrome, PCKD, OSA, vascular malformations
Meds e.g. anticoagulation
What % of strokes are ischaemic?
85%
What most commonly causes ischaemic strokes?
Thrombus - often as a complication of atherosclerosis
Embolus - often as a complication of atherosclerosis of carotid arteries or AF
Others: intracranial or extracranial vessels disease or hamatological conditions
What most commonly causes haemorrhagic strokes?
Intracerebral haemorrhage - commonly due to hypertension
Subarachnoid haemorrhage - most commonly rupture of intracranial saccular aneurysms. Others are AVMs, arterial dissections, anticoag use
Short-term complications of strokes?
Haemorrhagic transformation of ischaemic stroke.
Cerebral oedema.
Delirium.
Seizures.
Venous thromboembolism — pulmonary embolism has been associated with 13–25% of deaths in the early period following stroke.
Cardiac complications — e.g. MI, CHD, AF, and arrhythmias are common due to shared aetiology.
Infection — e.g. aspiration pneumonia, urinary tract infection, and cellulitis from infected pressure sores.
Long-term complications of stroke?
Most common:
Urinary incontinence, malnutrition, acute confusion, pain, chest infection, VTE
Mobility issues - hemiparesis, hemiplegia, ataxia, falls, spasticity, contractures
Sensory problems e.g. touch, pain, temp
Pain e.g. neuropathic, MSK
Fatigue
Dysphagia, dehydration and malnutrition
Sexual dysfunction
Increased risk of pressure sores due to reduced mobility
Visual problems e.g. nystagmus, altered acuity, hemianopia, diplopia
Cognitive problems
Difficulties with ADLs
Emotional and psychological
Communication problems e.g. aphasia, apraxia, dysarthria
Loss of income
Prognosis for stroke?
30 day mortality for ischaemic stroke is 12 per 100 and for haemorrhagic stroke its 31 per 100
1 in 7 people with acute stroke die in hospital
Ischaemic stroke in people with AF is associated with greater mortality and disability
Mortality rates in haemorrhagic stroke are higher than ischaemic stroke
Overall mortality at 6 months following subarachnoid haemorrhage is >25%
Risk of recurrent stroke within 90 days after first stroke is 5%. In 10 years its 40%
Factors associated with worse outcomes in haemorrhagic stroke?
Haemorrhage volume
Advanced age
Impaired consciousness at presentation
Rupture of haematoma into the ventricular system
Symptoms of a TIA?
Sudden onset, focal neurological deficit which has completely resolved within 24 hours
Unilateral weakness or sensory loss
Dysphasia
Ataxia, vertigo or loss of balance
Syncope
Sudden transient loss of vision in 1 eye, diplopia or homonymous hemianopia
CN defects
Symptoms of a stroke?
Confusion, altered level of consciousness and coma
Headache - either insidious onset and gradually increasing (intracranial haemorrhage) or sudden severe headache (subarachnoid headache)
Unilateral weakness or paralysis in face, arm or leg
Sensory loss - paraesthesia or numbness
Ataxia
Dysphasia
Dysarthria
Visual disturbances - homonymous hemianopia or diplopia
Gaze paresis
Photophobia
Dizziness, vertigo or loss of balance
Nausea and vomiting
CN deficit
Difficulty with fine motor coordination and gait
Neck or facial pain
Symptoms of acute vestibular syndrome (i.e. posterior circulation)?
acute, persistent, continuous vertigo or dizziness with nystagmus, nausea or vomiting, head motion intolerance, and new gait unsteadiness.
What are stroke mimics?
Metabolic - hypoglycaemia, hypoxia
CNS - old strokes, epilepsy, Todd’s paresis, migraine, mass lesion, MS, encephalitis, syncope
Functional neurological disorder
What is functional neurological disorder?
The name given for symptoms in the body which appear to be caused by problems in the nervous system but which are not caused by a physical neurological disorder
I.e. medically unexplained
Stroke chameleons?
Acute confusional state
Abnormal movements or seizures
PNS symptoms e.g. wrist drop
Acute vestibular syndrome
Atypical symptoms
Investigations for suspected stroke?
Non-contract CT head scan within 1 Hour!
FBC and ESR
Blood glucose
Total cholesterol
U&Es
ECG
Carotid imaging for anterior events
Selective tests - ECHO, vasculitis and thrombophilia screen, 24 hour ECG tape for paroxysmal AF
Regional blood supply to cerebrum?
Anterior cerebral arteries - anteromedial cerebrum
Middle cerebral arteries - lateral part of brain
Posterior cerebral arteries - medial and lateral posterior cerebrum
Bamford classification of stroke?
The following criteria should be assessed:
1. unilateral hemiparesis and/or hemisensory loss of the face, arm & leg
2. homonymous hemianopia
3. higher cognitive dysfunction e.g. dysphasia
TACS - all 3 of above criteria
PACS - 2 of the above criteria OR higher cerebral dysfunction alone
LACS - presents with 1 of the following: pure sensory stroke; pure motor stroke; sensory-motor stroke; ataxic hemiparesis
POCS - presents with 1 of the following: CN palsy and a contralateral motor/sensory deficit, bilateral motor/sensory deficit, conjugate eye movement disrder, cerebellar dysfunction, isolated homonymous hemianopia
Management of acute ischaemic stroke when pt presents within 4.5 hours of symptom onset?
Arrange immediate emergency admission to an acute stroke facility
300mg aspirin orally or rectally asap as soon as haemorrhagic stroke is ruled out (but within 24 hours) - use for 2 weeks then start long term anti thrombotic agent
Thrombolysis with alteplase within 4.5 hours of symptoms and once haemorrhage has definitely been excluded
Mechanical thrombectomy in some cases
Long term:
Clopidogrel
If AF or flutter consider additional anticoag
High intensity statin
Lifestyle changes
Who can be considered for thrombectomy?
Confirmed acute stroke….
- And confirmed occlusion of proximal anterior circulation on imaging = do it within 6 hours alongside IV thrombolysis if within 4.5 hours
- And confirmed occlusion of proximal anterior circulation on imaging + potential to salvage brain tissue = offer between 6-24 hours
- And confirmed occlusion of proximal posterior circulation on imaging (basilar or posterior cerebral artery) + potential to salvage brain tissue = offer asap with Iv thrombolysis if within 4.5 hours
Which ethnicity has a higher risk of intracranial haemorrhage as a cause for stroke?
Asian - accounts for up to 30% of all strokes in them compared to 10-15% in whole population
What is cerebral amyloid angiopathy?
a condition in which proteins called amyloid build up on the walls of the arteries in the brain. CAA causes bleeding into the brain (hemorrhagic stroke) and dementia
Management of acute ischaemic stroke when pt presents after 4.5 hours of symptom onset?
Arrange immediate emergency admission to an acute stroke facility
300mg aspirin orally or rectally asap as soon as haemorrhagic stroke is ruled out (but within 24 hours) - use for 2 weeks then start long term anti thrombotic agent
Mechanical thrombectomy in some cases
Long term:
Clopidogrel
If AF or flutter consider additional anticoag
High intensity statin
Lifestyle changes
Management of a haemorrhagic stroke?
Refer for neurosurgical assessment as surgical intervention may be required
Consider antihypertensives if they present within 6 hours of symptom onset and systolic bp is 150-220
Stop and reverse any anticoagulants
Long term:
Maintain bp
Avoid statins, anticoagulants and aspirin (if worries about risk of vascular events or AF then seek specialist advice)
Management of TIA?
300mg aspirin immediately (unless bleeding disorder, taking anticoagulant, takes low-dose aspirin regularly or aspirin is contraindicated)
Urgent carotid imaging - Carotid artery endarterectomy if suffered stroke/TIA in carotid territory and not severely disables and carotid stenosis >70%
Secondary prevention:
Antiplatelet therapy - clopidogrel
High intensity statin
How to avoid complications when managing strokes?
Dysphagia management - aspiration and nutrition
Early sitting out and mobilisation
Careful handling and positioning - so they dont get shoulder pain
Preventing pressure sores
Avoid urinary catheters if possible
DVT prevention after first 2 weeks e.g. compression stockings
Good environment - to help with mental health
Ethical issues with strokes?
Autonomy and restraint e.g. nasogastric tubes, use of DOLS
Capacity decisions e.g. dysphasia
Dignity
End of life decisions
Safegaurding and best interests
Secondary prevention after strokes?
Advice for lifestyle, driving, travel etc
Clopidogrel 75mg Od
(Some may have dual therapy with aspirin + clopidogrel)
Atorvastatin 20-80mg od
Antihypertensives with target <130/80 after first 2 weeks
If paroxysmal, persistant or permenant AF or flutter… after 14 days in disabling ischaemic strokes use warfarin or direct thrombin or factor Xa inhibitor (with 300mg daily aspirin in the interim)
Aim of statin therapy in secondary prevention of stroke?
To reduce non-HDL cholesterol by >40%
Advice on driving after stroke/TIA?
Single TIA or stroke - 4 weeks - dont need to notify DVLA
Multiple TIAs - 3 months and must notify DVLA
Typical sites of intracerebral haemorrhages?
Where end-penetrating arteries are e.g/ lenticulostriate arteries, thalamostriate arteries, parapontine arteries, cerebellar arteries
Clinical presentation of intracerebral haemorrhage?
A progressive headache with evolving neurological deficit over mins-hours
The initial deficit can be from mass effect
Clinical signs are dependant on anatomical site
Not unusual for a secondary ischaemic stroke from vasospasm
Could also cause focal onset seizures
Typical sites for subarachnoid haemorrhage?
At bifurcation or division of arteries
Clinical presentation of subarachnoid haemorrhage?
A thunderclap headache - hyperacute headache that reaches its maximum at onset within 1-5 minutes, often occipital
Nausea and vomiting
Meningism
Sudden collapse or coma
Seizures
1/3rd may die within hours
May evolve to cause ischaemic stroke from vasospasm
How do subdural haemorrhages present?
Altered mental status
Focal neurological deficits
Headaches - often localised to 1 side and worsens over time
Seizures may occur
N&V
Drowsiness
Signs of raised ICP
Memory loss, personality changes and cognitive impairment
Causes of subarachnoid haemorrhage?
Most commonly head injury
In the absence of trauma…
Intracranial aneurysm - saccular berry aneurysm
AVMs
Pituitary apoplexy
Mycotoxins aneurysms
Management of confirmed aneurysmal subarachnoid haemorrhage?
Support - bed rest, analgesia, VTE prophylaxis, discontinue anti thrombotic and reverse anticoagulation if present
Prevent vasospasm using a course of oral nimodipine
Interventional neuroradiolofy procedures or craniotomy + clipping within 24 hours
Important predictive factors in subarachnoid haemorrhage
conscious level on admission
age
amount of blood visible on CT head
What typically causes acute subdural haematomas?
High-impact trauma
What typically causes chronic subdural haematomas?
Rupture of the small bridging veins within the subdural space rupture and cause slow bleeding. Elderly and alcoholic patients are particularly at risk of subdural haematomas since they have brain atrophy and therefore fragile or taut bridging veins.
Shaken baby syndrome also
What is virchows triad?
3 contributing factors in the formation of thrombosis:
venous stasis, vascular injury, and hypercoagulability
Venous stasis is the most consequential of the three factors, but stasis alone appears to be insufficient to cause thrombus formation
Is oestrogen a risk factor for stroke?
Only in the premenopausal women
- check this??????
Symptoms specific to anterior cerebral artery stroke?
Contralateral hemiparesis and sensory loss - Lower extremity > upper!
Leg weakness affects distal and proximal muscles equally but arm weakness is milder and affects proximal muscles more (think about homunculus)
Face is spared
Symptoms specific to middle cerebral artery stroke?
Contralateral hemiparesis and sensory loss - Upper extremity > lower
Contralateral homonymous hemianopia
Contralateral UMN facial weakness
Aphasia
Symptoms specific to posterior cerebral artery stroke?
Contralateral homonymous hemianopia with macular sparing
Visual agnosia
Symptoms specific to posterior inferior cerebellar artery stroke (Wallenberg syndrome/lateral medullary syndrome)?
ipsilateral: ataxia, nystagmus, dysphagia, facial numbness, cranial nerve palsy e.g. Horner’s
contralateral: limb sensory loss
Symptoms specific to anterior inferior cerebellar artery stroke (lateral pontine syndrome)?
Ipsilateral facial paralysis and deafness, facial pain and temperature loss
Contralateral: limb/torso pain and temperature loss
Ataxia, nystagmus
Symptoms specific to retinal or ophthalmic artery stroke?
Amaurosis fugax
Symptoms specific to basilar artery stroke?
Locked-in syndrome
What is webers syndrome?
A stroke affecting the branches of the posterior cerebral artery that supply the midbrain
Symptoms specific to weber’s syndrome?
Ipsilateral CN III palsy
Contralateral weakness of upper and lower extremities as involved with crus cerebri where motor fibres run
Common sites for lacunar strokes?
basal ganglia, thalamus and internal capsule
Symptoms specific to thalamic stroke?
Changes in mood and emotion
Sensation disturbances
Movement disorders
Visual and auditory problems
Symptoms of cortical venous sinuses thrombosis?
Headache due to raised ICP
Seizures due to irritation of blood
Focal neurological symptoms and signs
Coma
What is a cerebral venous sinus thrombosis?
The presence of a blood clot in the rural venous sinuses, the cerebral veins or both
Why is it important not to over treat blood pressure in the acute phase after a stroke?
As this is the body’s physiological mechanism to increase blood flow to the collaterals to prevent brain ischaemia
Only treat if >180
When do you start anticoagulation in pt with stroke and AF?
Approx 2 weeks after initial presentation start warfarin or a NOAC - any earlier there is risk of tar formation to haemorrhagic stroke
Anterior spinal artery syndrome symptoms?
Complete bilateral motor loss below level
Bilateral loss of spinothalamic fnctuion below the level
Retained bilateral posterior column function
(Anterior spinal artery supplied 2/3rds of the anterior spinal cord. The posteror 1/3rd of the spinal cord is supplied by 2 posterior spinal arteries)
What is an extradural haematoma?
Bleeding into the space between dura mater and the skull
Majority occur in the temporal region where skull fractures cause a rupture of the middle meningeal artery
What are subdural haematomas?
Bleeding into the outermost meningeal layer
Most commonly around frontal and parietal lobes
Most commonly venous so slower onset of symptoms
What are subarachnoid haemorrhages?
Intracranial haemorrhages with blood in the subarachnoid space
Can be traumatic or spontaneous
Causes of spontaneous subarachnoid haemorrhages?
Intracranial aneurysms in 85%
AVMs
Pituitary apoplexy
Mycotic aneurysms
Where do hypertension-induced haemorrhagic strokes most commonly occur?
small penetrating arteries originating from basilar arteries or the anterior, middle, or posterior cerebral arteries
Presentation of lacunar strokes?
Pure sensory stroke
Pure motor stroke
Sensory-motor stroke
Ataxic hemiaresis
No loss of higher cerebral functions
What is a lacunar stroke?
A subcortical stroke that occurs secondary to small vessel disease - one of the small arteries that supplies the brain’s deep structures is blocked
What classification is used to classify strokes based on initial symptoms?
Oxford Stroke Classification
Aka Bamford Classification
What is broca’s aphasia?
Aka expressive aphasia due to damage in Broca’s area in left frontal lobe
Difficulty trying to find and say the right words but comprehension and understanding of language remains intact
Really effortful speech. May speak in short sentences
What is wernicke’s aphasia?
Damage to wernicke’s area in the left temporal lobe
Able to speak well and use long, smooth sentences but what they say does not make sense
Inability to grasp the meaning of words, intrusion of irrelevant words in severe cases
Pt may not be aware of their language deficits
May say words that sound similar e.g. saying food instead of mood. Or they may just say things that seem completely random
Can affect writing too
What is apraxia of speech?
When an individuals cannot translate conscious speech plans into motor plans = limited and diffiuclt speech ability = slow and effortful speech
I.e. they cannot coordinate lips and tongue the right way to make sounds due to the brain being unable to plan muscle movements
What is dysarthria?
A motor disorder!!
Damage to PNS e.g. muscles, rather than damage to specific brain areas
Difficulty speaking because muscles you use for speaking are weak.
Causes slurred, unclear speech
What is dysphasia?
Often used interchangeably with aphasia but can also refer to a broader range of language difficulties
Difficulty with language comprehension, expression or both
What is an intracranial venous thrombosis?
When a blood clot forms in the brain’s venous sinuses which stops blood from draining out of the brain
It can cause cerebral infarction but is much less common than arterial causes
Most commonly involved vein in intracranial venous thrombosis?
Sagittal sinus thromboses
Features of intracranial venous thrombosis?
Headache
N&V
Reduced consciousness
Who is more likely to get an intracranial venous thrombosis?
Women 20-35
Pregnancy, puerperium or oral coinyraception
Haematological disorders - thrombophilias, TTP, polycythemia
Dehydration
Infection e.g. sinusitis
Inflammatory disorders e.g. Behçet’s disease or SLE
Meningitis
Investigations for intracranial venous thrombosis?
MRI venoraphy is gold standard
(Non-contrast CT had is normal in 70% of pt)
Management of intracranial venous thrombosis?
Anticoalant with LWMH and then warfarin for longer term anticoagulation
Howdo Sagittal sinus thrombosis present?
may present with seizures and hemiplegia
How may cavernous sinus thrombosis present?
Ophthalmoplegia: CN3,4 and 6 damage - 6 occurs first
Trigeminal nerve involvement may lead to hyperaesthesia of upper face and eye pain
“Proptosis, chemosis and painful ophthalmoplegia)
Risk factors specifically for haemorrhagic stroke?
Anticoagulation therapy
Bleeding disorders
AVMs
Cerebral aneurysms
Risk factors specifically for ischaemic stroke?
Smoking
Hyperlipidaemia
Diabetes mellitus
AF
What is amaurosis fugax?
Transient vision loss due to lack of blood flow from retinal aretry, ophthalmic artery or ciliary artery
Cause of amaurosis fugax?
Atherosclerotic emboli from carotid artery
What is the mechanism for dysphagia following a stroke?
Oropharyngeal motility issues - disruption of the bolus flow from mouth to pharynx
Which swallow assessment is done after stroke
Initially a bedside assessment with sip and swallows is done
A videofluoroscopy is gold standard but is less commonly done
What is nominal dysphasia?
Inability to recall names of people or objects correctly
What is the term used to describe the flexion of upper limbs following a stroke?
Clasp knife spasticity
