Stroke (haemorrhagic and ischaemic) Flashcards
Define:
Rapid permanent neurological deficit from a cerebrovascular insult lasting more than 24 hours.
Can be classified by location - anterior or posterior or by pathology (infarct vs haemorrhage)
Aetiology of ischaemic strokes:
85% are ischaemic stroke due to infarcts:
-Thrombosis - Lacunar infarcts (small vessels), middle cerebral artery, dehydration and thrombophilia
Emboli - Carotid dissection , AF, carotid atherosclerosis (can be venous clots from the leg if there is a septal defect such as VSD)
Hypotension - this is due to the BP auto-regulatory system meaning that there is loss in the watershed areas.
Other - vasculitis and cocaine
Aetiology of hameorrhagic strokes:
HTN Amyloid angiopathy Arteriovenous malformations Anticoagulation Vasculitis Trauma Tumours SAH Charcot-Bouchard aneurysms = aneurysms in the brain vasculature in small vessels
Risk factors:
HTN Smoking DM Obesity + alcohol = weaker FHx Dyslipidemia Hx of stroke Age AF Sickle cell anaemia
Epidemiology:
Common 2/1000
Usually in 70+
3rd biggest killer in industrialised countries
Symptoms:
SUDDEN ONSET
Weakness
Sensory, visual and cognitive impairment
Impaired co-ordination
Head or neck pain
HX of AF, MI or carotid artery stenosis
Collateral weakness and loss of facial tone to the lesion
General signs:
Ataxia Aphasia (receptive or expressive) Weakness Flaccid paralysis --> spasticity (hypertonia) Hyperrelfexia Hemiparesis Forehead sparing On the contralateral side to the lesion Clonus Babiniski +ve Sensory and visual deficits
Signs of lacunar infarcts:
• Affecting the internal capsule or pons: pure sensory or motor deficit (or both)
Affecting the thalamus: loss of consciousness, hemisensory deficit
Affecting the basal ganglia: hemichorea, hemiballismus, parkinsonism –> DYSKINESIA
Signs of anterior circulation stroke:
Behaviour changes
Lower limb affected greater than the upper limb
Contralateral hemiparesis
> Confusion
Signs of middle artery stroke (CLASSIC STROKE):
Facial weakness – contralateral side
Hemiparesis (motor cortex) – contralateral upper limb weakness
Hemisensory loss (sensory cortex) - contralateral
Apraxia
Hemineglect (parietal lobe)
If left sided will also cause aphasia - Receptive or expressive dysphasia (due to involvement of Wernicke’s and Broca’s areas)
Quadrantanopia (if superior or inferior optic radiations are affected)
Signs of posterior circulation stroke:
Homonymous contralateral hemianopia
Visual agnosia
Investigations:
Pulse and BP - to check for HTN and AF
CT HEAD - this will show if it is an infarct or a haemorrhage (1st line)
ECG or ECHO - show arrhythmias that may have caused the clot
Doppler Carotid USS- for TIA
MRI brain - more sensitive but do CT first
CT cerebral angiogram - show dissections or stenosis
Bloods - clotting and glucose (should be 4 -11)
Management of hyperacute stroke:
<4.5 hours
- rTPA (alteplase)
- 24hrs later aspirin
- Make sure to exclude haemorrhage first with a CT head
Management of acute stroke:
300mg aspirin to prevent further thrombosis
o Heparin anticoagulation considered if there is a high risk of emboli recurrence or stroke progression
o Formal swallow assessment (NG tube may be needed)
o GCS monitoring
o Thromboprophylaxis
Secondary prevention:
o Standard: antiplatelet clopidogrel 75mg daily
o May also use modified-release dipyridamole or aspirin if clopidogrel contra-indicated
o If there is paroxysmal, persistent or permanent AF: warfarin anticoagulation
o Control risk factors: hypertension, hyperlipidaemia, treat carotid artery disease (especially in haemorrhagic)
• Surgical Treatment - carotid endarterectomy or thrombectomy
