Stroke Flashcards
What is strokeʔ
ʀapid, permanent neurological decline caused by a cerebrovascular event.
That lasts for more than 24hours.
(TɪA lasts for less than 24hours)
What the 2 types of strokeʔ
1) ischemic stroke
2) hemorrhagic
Strokes can be caused by an infarction (80%) or hemorrhage.
What are the causes of ischaemic strokeʔ
1) Thrombosis —> small vessel occlusion
2) Cardiac emboli (Afib, endocarditis, Mɪ)
3) hypotension (sepsis)
What are the causes of haemorrhagic strokeʔ
1) hypertension
2) trauma
3) aneurysm rupture (berry aneurysm in circle of willis)
4) anticoagulation
5) thrombolysis
What is the annual incidence of strokeʔ
2 in 1000
What are the presenting symptoms of a strokeʔ
- sudden onset
- weakness on one side of body
- impaired consiousness
- sensory,
- blurred or loss of vision,
- cognitive impairment (confusion, difficulty finding words)
- sudden, severe headache
- dizzy
- loss of balance
What are the symptoms of an infarct of the area supplied by the anterior cerebral artery ʔ
- lower limb weakness (motor cortex)
- confusion (frontal lobe)
What are the symptoms of an infarct of the area supplied by the middle cerebral arteryʔ
- Facial weakness ( motor cortex)
- hemiparesis (motor cortex)
- hemisensory loss (somatosensory cortex)
- apraxia (difficulty initiating speech) (parietal lobe)
- ʀeceptive / expressive dysphasia (difficulty understanding words and difficulty finding the words to express themselves.
- Quadrantanopia (loss of vision from one quadrant) (superior or inferior optic radiation)
Occlusion of which artery leads to hemianopia (loss of half of visual field)ʔ
Posterior cerebral
What are the modifiable risk factors of strokeʔ
Cardiacː
- ischaemic heart disease
- atrial fibrillation
- heart valve disease
Vascularː
- hypertension
- periferal vascular disease
- carotid bruit
ʟifestyleː
- alcohol
- smoking
- hyperlipidaemia
Drugsː
-OCP
ɪnfectiousː
-syphilis
- Diabetes
- previous TɪA
- increased clotting
What does a cerebral infarct lead toʔ
- contrelateral sensory loss or hemiplegia (weakness of one side of body)
- dysphasia (inability to express or understand speech)
- homonymous hemianopia (same side of vision lost in both eyes)
ɪnfarct of what area of the brain leads to locked in syndromeʔ
Brainstem
What is the immediate response to a patient presenting with strokeʔ
1) protect airway
2) pulse, BP, ECɢ
3) Urgernt CT (haemorrhagicʔ)
4) Or urgent Mʀɪ (acute infarct)
5) Thrombolysis if vessel occlusion
6) ɴil by mouth (dysphagia —> choking risk)
7) Antiplatelets (only if haemorrhagic cause excluded)
Where is a subdural haematomaʔ and what does it look like on a CT scanʔ
Subdrual haematoma is a collection of blood in the subdural space. That is the space between the dura mater and the arachnoid mater.
ɪt looks like a banana on the CT scan.
What are the symptoms of a subdural haematomaʔ
Can be caused by a rupture of vein following a light head injury. The symptoms may only occur days to weeks after the injury.
symptoms includeː
- headache
- drowsiness
- confusion
- fluctuating consciousness
- siezures
-raised ɪCP
Who is at risk of a subdural haematomaʔ
Elderly because atrophy of the brain makes veins more vulnerable
sudden headache, followed by vomiting , collapse and coma is significant of….
subarachnoid haemorrhage
(thunderclap headache)
Differentialsː
Cerebellar haemorrhage - headache followed by stupr/coma, ocular palsies, nystagmus
What haemorrage could cause acute hydrocephalusʔ
Cerebellar haemorrhage.
symptomsː(brainstem/ cerebellar involvement) stupor/coma, ocular palsies, nystagmus
ʀupture of what type of aneurysm could cause an intracerebral haemorrhageʔ
Charcot - bouchard aneurysm
Following what type of haemorrhage could there be neck stiffness , +ve kernig’s sign and papilloedemaʔ
major Subarachnoid haemorrhage can show signs of meningism.
What invx should be done in a pt presenting with strokeʔ
1) Bloods ː FBC, U+E’s, Clotting profile, lipids
2) ECɢ (Atrial fibʔ)
3) Echocardiogram (valvular endocarditisʔ - cardiac source of emboli)
4) Carotid doppler USS (carotid artery disease)
5) CT head (detect haemorrhage)
6) Mʀɪ (identify infarction)
7) CT-cerebral angiogram to identify occlusion or intracranial stenosis.
What is the treatment of a non haemorrhagic stroke, if less than 4.5 hours from onset of symptomsʔ
ɪntravenous thrombolysis
When is heparin anticoagulation in a stroke patient consideredʔ
ʜeparin may be given in a non-haemorrhagic stroke if there is a high risk of embolu recurrence or stroke progression e.g. carotid dissection, carotid stenosis ect.)
Why would a formal swallow assesment be essential in a stroke patientʔ
Stroke can cause dysphagia so there is choking risk.
Swallow assment needed to decide whether ɴɢ tube necessary.
What is a TIA?
Sudden onset of CNS decline that lasts less than 24h.
What is the usual pathogenesis of TIA?
emboli in the small vessels of brain causing small infarct (lacunar infarct)
- Atherothromboembolism from carotid
- cardioembolism (Afib, mural thrombus, post MI)
- hyperviscosity (e.g. polycythemia or sickle cell)
What are the signs of a TIA?
Mimics stroke
- facial weakness
- aphasia
- amaurosis fugax (progressive vision loss in one eye due to emboli in retinal artery)
Frontal sparing is a sign of:
a) Stroke (umn lesion)
b) facial nerve palsy (LMN lesion)
Frontal sparing is a sign of stroke.
What is the sign of a carotid source of emboli in TIA?
carotid bruit
When examining a TIA pt what signs should you look out for that could indicate the cause of the event?
- carotid bruit
- increased Blood pressure
- heart murmur (from valve disease)
- atrial fibrillation
- fundoscopy may show retinal artery embolism
What are the differential diagnoses for TIA?
- hypoglycaemia
- migraine aura
- focal epilepsy
- hyperventilation
- retinal bleed
What invx are done for TIA?
The Invx aim to find a cause for the TIA and assess vascular risk:
1) Bloods (FBC, ESR, U+Es, Glucose, lipids)
2) CXR (afib?)
3) Carotid doppler +/- angiography (carotid stenosis)
4) CT / MRI to identify infarct
What treatment should be given to a pt with TIA?
1) control cardiovascular risk factors:
- Blood pressure,
- hyperlipidemia,
- stop smoking,
2) Antiplatelet drugs:
- clopidogrel
- aspirin 300mg/d for 2wks, then 75mg/d
3) Warfarin if cardiac emboli
4) Carotid endartectomy if more than 70% stenosis
When should TIA lead to prompt referral?
ABCD2 criteria
ABCD2 if score 6+ then high stroke risk within next week. If score 4+ then must be assessed within 24hrs.
A- Age 60+ (1 point)
B - blood pressure more than 140/90 (1 point)
C - clinical features - unilateral weakness (2 points), speech disturbance without weakness (1 point)
D - duration of symptoms - 1hr+ (2 points), 10-59 mins (1 point)
D - diabetes
