Stroke (N) Flashcards
Define stroke.
A clinical syndrome consisting of rapidly developing clinical signs of focal (or global) disturbance of cerebral function, lasting more than 24 hours or leading to death, with no apparent cause other than that of vascular origin
What are the two types of stroke?
- ischaemic stroke (85%) - cerebral infarction due to insufficient blood flow due to a thrombus or embolus
- haemorrhagic stroke (15%) - cerebral infarction due to haemorrhage (rupture of blood vessel causing leakage of blood into brain)
What is a central venous sinus thrombosis (stroke)?
Rare form of stroke that occurs due to thrombosis of the dural venous sinuses
What are some risk factors for stroke? (7)
- age >65
- hypertension
- diabetes
- AF
- obesity
- smoking
- high cholesterol
What is the main feature of stroke, regardless of its location?
Acute onset
What are the five key functions affected by stroke?
- motor
- sensation
- speech
- balance
- vision
What are some general clinical features of a stroke? (7)
- unilateral weakness / paralysis
- sensory, visual or cognitive impairment
- dysphasia
- ataxia
- impaired coordination
- impaired consciousness
- head/neck pain (if carotid or vertebral artery dissection)
What are the types of stroke according to the Bramford stroke classification? (4)
- total anterior circulation stroke (TACS)
- partial anterior circulation stroke (PACS)
- lacunar syndrome (LACS)
- posterior circulation syndrome (POCS)
What are the criteria for a total anterior circulation stroke (TACS)?
Affects middle and anterior cerebral arteries
All three of the following:
- unilateral weakness (and/or sensory deficit) of the face, arm and leg
- homonymous hemianopia
- higher cerebral dysfunction (dysphasia, visuospatial disorder)
What are the criteria for a partial anterior circulation stroke (PACS)?
Involves smaller arteries of anterior circulation e.g. upper/lower division of MCA
Two of the following:
- unilateral weakness (and/or sensory deficit) of the face, arm and leg
- homonymous hemianopia
- higher cerebral dysfunction (dysphasia, visuospatial disorder)
What are the criteria for lacunar syndrome (LACS)?
One of the following:
- pure sensory stroke
- pure motor stroke (unilateral weakness of face and arm, arm and leg or all three)
- sensori-motor stroke
- ataxic hemiparesis
What are the criteria for posterior circulation syndrome (POCS)?
One of the following:
- cranial nerve palsy and a contralateral motor/sensory deficit
- bilateral motor/sensory deficit
- conjugate eye movement disorder (e.g. gaze palsy)
- isolated homonymous hemianopia or cortical blindness
- (cerebellar/brainstem syndromes, LoC)
What is a ‘classic’ stroke?
Middle cerebral artery stroke
What features would you see in a middle cerebral artery stroke? (4)
- contralateral weakness and sensory loss in upper limbs and lower half of face
- contralateral facial weakness
- contralateral hemiparesis (motor cortex) - upper limb weakness
- contralateral hemisensory loss (sensory cortex)
- contralateral homonymous hemianopia
- aphasia
- damage to Broca’s area (left frontal lobe) –> expressive aphasia (speech production)
- damage to Wernicke’s area (left temporal lobe) –> receptive aphasia (speech comprehension)
- dysarthria, dysphagia, apraxia
What would damage to Broca’s area (left frontal lobe) cause in MCA stroke?
Expressive aphasia (speech production)
What would damage to Wernicke’s area (left temporal lobe) cause in MCA stroke?
Receptive aphasia (speech comprehension)
What features would you see in an anterior cerebral artery stroke? (4)
- contralateral weakness and sensory loss in lower limb (hemiparesis)
- abulia (behaviour changes, intellect, executive function etc)
- urinary incontinence
- confusion
What features would you see in a posterior cerebral artery stroke? (6)
- contralateral homonymous hemianopia with macular sparing
- visual agnosia (difficulty recognising familiar objects/faces)
- contralateral sensory loss (or motor loss, in all 4 limbs)
- memory deficits
- vertigo
- nausea
What do you see on stroke of midbrain branches of posterior cerebral artery?
Ipsilateral oculomotor (CN III) palsy (down and out eye) and contralateral weakness of the upper and lower extremity
(Weber’s syndrome)
What features would you see in a posterior circulation stroke? (3+6)
- damage to the brainstem
- ipsilateral symptoms
- DANISH (cerebellar signs):
- Dysdiadochokinesia
- Ataxia
- Nystagmus
- Intention tremor
- Slurred speech
- Hypotonia
What would you see in a posterior inferior cerebellar artery (PICA) stroke AKA lateral medullary syndrome? (Posterior circulation stroke)
Lateral medullary syndrome:
- cerebellar signs (DANISH)
- nystagmus
- vertigo and vomiting
- ipsilateral facial pain and temperature loss
- contralateral upper and lower limb pain and temperature (sensory) loss
- ipsilateral Horner’s syndrome
What would you see in an anterior inferior cerebellar artery (AICA) stroke? (Posterior circulation stroke)
- sudden onset vertigo and vomiting
- ipsilateral facial paralysis
- deafness
What is Weber’s syndrome and what are its features? (2)
A form of midbrain stroke characterised by:
- ipsilateral CN III palsy (down and out eye)
- contralateral hemiparesis
What features would you see in a pontine haemorrhage? (3)
- reduced GCS
- paralysis
- bilateral pin-point pupils
What feature would you see in a basilar artery stroke?
Locked in syndrome - decreased GCS and motor symptoms
What features would you see in a posterior communicating artery aneurysm? (2)
- CN III palsy (eye down and out, dilated pupil)
- eye pain
What are the four types of aphasia and their symptoms?
- Broca’s aphasia - speech non-fluent, comprehension normal, repetition impaired
- Wernicke’s aphasia - speech fluent, comprehension abnormal, repetition impaired
- conduction aphasia (arcuate fasciculus) - speech fluent, comprehension normal, repetition impaired (aware of errors)
- global aphasia - speech non-fluent, comprehension abnormal, repetition impaired
What acronym can we use to diagnose stroke in the community?
BE FAST:
- Balance
- Eyes
- Face (one side drooping)
- Arms or legs (weakness)
- Speech
- Time
What score can we use to tell the difference between stroke and stroke mimic?
ROSIER (Recognition Of Stroke In Emergency Room)
Stroke likely if score >0
What are the first-line investigations for stroke? (4)
- non-contrast CT head (1st line radiological investigation)
- serum glucose - rule out hypo/hyperglycaemia
- serum electrolytes - rule out metabolic disturbances
- serum urea and creatinine - rule out AKI/renal failure
What scans do we do in suspected stroke? (2)
- non-contrast CT head - to exclude haemorrhage and confirm ischaemic stroke (NB CT does not rule out ischaemic stroke)
- CT angiogram - look for which vessel is occluded
What might non-contrast CT head show in ischaemic stroke?
- may show areas of low density in the grey and white matter of the territory (may take time to develop)
- other signs include the ‘hyperdense artery’ sign corresponding with the responsible arterial clot (visible immediately)
What might non-contrast CT head show in haemorrhagic stroke?
Typically show areas of hyperdense material (blood) surrounded by low density (oedema)
How do we investigate stroke after the patient has been treated?
Look for cause of stroke through e.g.
- echocardiogram (structural heart disease)
- ambulatory ECG (AF)
- carotid doppler (carotid atherosclerosis) - if >70% occlusion do carotid endarterectomy (surgery to remove plaque from carotid)
What do we do if carotid doppler shows >70% occlusion (stroke)?
Carotid endarterectomy - surgery to remove plaque from carotid
What score can we use to measure disability of someone after a stroke?
Barthel index
What are some differential diagnoses for stroke? (10)
- hypertensive encephalopathy
- hypoglycaemia
- complicated migraine
- seizure and postictal deficits (Todd’s paresis)
- conversion and somatisation disorders
- Wernicke’s encephalopathy
- brain tumour
- sepsis
- intracranial venous thrombosis (non-contrast CT shows hyperdensity in affected sinus)
- cavernous sinus thrombosis (chemosis, exophthalmos and periorbital sweating)
What is the first step to stroke management?
CT head before thrombolysis to rule out haemorrhage (especially if on warfarin/DOAC/bleeding disorder)
What do we do for ischaemic stroke management after head CT ruled out haemorrhage, if <4.5h from onset?
Thrombolysis - IV alteplase (recombinant tissue plasminogen activator)
How do we manage ischaemic stroke - anterior circulation stroke (ACA or MCA) within 6h?
Mechanical thrombectomy + thrombolysis (IV alteplase)
How do we manage ischaemic stroke - 6-24h and limited infarct core in anterior circulation?
Mechanical thrombectomy
How do we manage ischaemic stroke - within 24h and limited infarct core in posterior circulation?
Mechanical thrombectomy + thrombolysis
What should BP be lowered to before thrombolysis (stroke)?
185/110 mmHg
When is thrombolysis contraindicated in stroke?
- previous intracranial haemorrhage
- seizure
- intracranial neoplasm
- suspected subarachnoid haemorrhage
- stroke/brain injury in preceding 3m
- lumbar puncture in preceding 7d
- GI haemorrhage in last 3wk
- active bleeding
- pregnancy
- oesophageal varices
- uncontrolled hypertension >200/120mmHg
- concurrent anticoagulation (INR>1.7)
- major surgery/trauma in last 2wk
How do we manage ischaemic stroke if >4.5h from onset?
Conservative management (aspirin PO 300mg daily) + swallow assessment
What do we do 2 weeks after ischaemic stroke? (2)
Secondary prevention:
- stop aspirin 300mg daily
- start clopidogrel 75mg daily for life (if not tolerated, aspirin + modified release dipyridamole)
What do we give patients with stroke risk due to AF?
Anticoagulation (DOAC) initiated 2 weeks after stroke
When do we do surgery for ischaemic stroke?
If ipsilateral carotid artery stenosis >50-70% (carotid doppler) –> carotid endarterectomy
Hypoglossal nerve at risk of damage
How do we manage haemorrhagic stroke?
Stop anticoagulants (if warfarin, consider vitamin K and prothrombin concentrate) and control BP if acute
When do we start anticoagulation following a stroke vs TIA?
- ischaemic stroke - after 2 weeks
- TIA - immediately once haemorrhage ruled out
What are some complications of stroke? (7)
- aspiration pneumonia
- cerebral oedema
- immobility - pressure sores, constipation, depression
- infections
- DVT
- cardiovascular events
- death
