Stroke Flashcards
Define Stroke
Rapidly developing focal neurological deficit that lasts for more than 24 hours, caused by cerebrovascular aetiology
Ischaemic (85%): vascular occlusion or stenosis
Haemorrhagic (15%): vascular rupture
Aetiology of Ischaemic Stroke
Transient or permanent critical reduction in cerebral blood flow due to arterial occlusion or stenosis
Small vessel (Lacunar): thrombotic occlusion of a small penetrating artery affected by lipohyalinosis
Large artery atherosclerosis: extracranial carotid or vertebral arteries
Cardioembolism: thrombus formation in the heart that embolises to the intracranial circulation (AF)
Dissection, vasculitis, venous thrombosis, sickle cell, antiphospholipid syndrome
Aetiology of Haemorrhagic Stroke
Vascular rupture → leakage of blood in the brain → raised ICP, toxic metabolites on the brain
Risk factors for stroke
Older age FMHx or PMHx stroke Hypertension Smoking Diabetes Atrial fibrillation Carotid artery stenosis Sickle cell disease Dysplipidaemia
Symptoms of Stroke
Sudden onset weakness, sensory or visual cognitive impairment Impaired coordination or consciousness Head or neck pain (in carotid or vertebral artery dissection) Aphasia Diplopia Dysarthria Vertigo Nausea/vomiting Altered consciousness or coma
IMPORTANT: ascertain time of onset
Signs of an anterior cerebral artery stroke on examination
Personality/behavioural changes Confusion Contralateral hemiparesis (leg>arm) -> lower limb weakness Mild sensory deficit
UMN: Spasticity, weakness, hyperreflexia, upgoing plantar response, pronator drift
Signs of a middle cerebral artery stroke on examination
Hemiparesis (Face > arm > leg) Hemisensory loss (somatosensory loss) Aphasia (receptive/Wernicke's or expressive/Broca's) Apraxia Hemineglect Quadrantanopia
UMN: Spasticity, weakness, hyperreflexia, upgoing plantar response, pronator drift
Signs of a posterior cerebral artery stroke on examination
Homonymous hemianopia
Visual agnosia
Prosopagnosia
UMN: Spasticity, weakness, hyperreflexia, upgoing plantar response, pronator drift
Signs of a small vessels stroke (lacunar) on examiantion
Internal capsule of pons: pure sensory or motor deficit (or combo)
Thalamus: Loss of consciousness, hemisensory deficit
Basal ganglia: hemichorea, hemiballismus, parkinsonism
UMN: Spasticity, weakness, hyperreflexia, upgoing plantar response, pronator drift
Signs of cerebellar stroke on examination
Dysdiadochokinesia Ataxia Nystagmus Intention tremor Slurred speech/staccato speech Hypotonia
UMN: Spasticity, weakness, hyperreflexia, upgoing plantar response, pronator drift
Investigations for stroke
Urgent CT head: haemorrhagic or ischaemic
Glucose: exclude hypoglycaemia U+Es: rule out electrolyte disturbance Renal function: before intervention Troponin: rule out MI FBC: before anticoagulation
ECG: identify arrhythmias e.g. AF
Echo: identify thrombus from AF
MRI: diagnostic - ischaemic infarcts appear bright
CT cerebral angiogram: normal (detect dissecitons or stenosis)
Carotid doppler: exclude carotid artery stenosis
Management for ischaemic stroke
- ABCDE, stabilise the airway - consider intubation + oxygen
- Urgent CT head - haemorrhagic or Ischaemic?
Onset within 4.5 hours
- Supportive and monitoring
- Thrombolysis with IV alteplase
- Consider mechanical thrombectomy
- 300mg Aspirin orally or rectall (stop after 2 weeks)
- Early mobilisation + anticoagulation with warfarin/DOAC
- Statins after 48 hours
Onset AFTER 4.5 hours:
- Supportive and monitoring
- Consider mechanical thrombectomy within 6 hours
- 300mg Aspirin orally or rectall (stop after 2 weeks)
- Early mobilisation + anticoagulation with warfarin/DOAC
- Statins after 48 hours
Management for haemorrhagic stroke
- ABCDE, stabilise the airway - consider intubation + oxygen
- Urgent CT head - haemorrhagic or Ischaemic?
- Refer to neurosurgery + airway protection + aspiration precaution
- Surgery to remove the haematoma with craniotomy
- ICP -> external ventricular drainage
- BP control using labetalol
- DVT prophylaxis
- correct any coagulopathies
Complications of stroke
Cerebral oedema (Raised intracranial pressure and local compression)
Immobility
Infection e.g. pneumonia, UTI, from pressure sores
DVT
Cardiovascular events (arrhythmias, MI, cardiac failure)
Death
Depression
Aspiration pneumonia
Prognosis for Stroke
Leading cause of long term disability
IV thrombolysis and dedicated stroke units are the only interventions shown to improve stroke outcome
