Cerebrovascular disease Flashcards
Define a stroke.
Insufficient blood supply to a part of the brain due to ischaemia (insufficient blood supply) or haemorrhage (bleeding).
Give 3 signs of a stroke.
Face - they cannot smile
Arms - they cannot lift their arms up
Slurred speech
(t)
What investigations would you do if you suspect someone has had/ is having a stroke?
Head CT - shows decreased density (darkness) which means oedema
Investigate primary cause - carotid duplex USS, echocardiogram, CXR (enlarged left atrium)
Which arteries and lobes may be affected if someone presents with leg weakness and sensory loss, gait apraxia, akinetic mutism, drowsiness and incontinence?
Anterior cerebral artery - supplies frontal areas of the brain which affect cognition
(lecture 23.3.18)
What is akinetic mutism?
Decrease in spontaneous speech and movement, stupurous state - frontal areas of the brain which affect cognition are affected.
Patient has right-sided leg and arm weakness, hemianopia, dysarthria, dysphasia and sensory loss. What part of the brain may be affected?
Left middle cerebral artery - supplies frontal, temporal and parietal areas.
Symptoms will be contralateral to the stroke.
You can also get facial droop.
Patient has homonymous hemianopia, cortical blindness, visual agnosia, prosopagnosia and dyslexia. What part of the brain may be affected?
Posterior cerebral artery - supplies temporal, parietal and occipital areas. Optic radiations travel through the posterior part of the brain. Primary visual centres. Headaches can sometimes be a symptom.
What could cause vertigo, nausea and vomiting?
Posterior circulation stroke affecting the basilar artery which supplies the brainstem, cerebellum and midbrain.
What is visual agnosia?
Visual agnosia = struggling to interpret visual information.
How are strokes classified?
Oxford stroke classification: 4 categories: Total anterior circulation stroke Partial anterior circulation stroke Posterior circulation stroke Lacunar circulation stroke
What are the main arteries of the anterior circulation?
Anterior cerebral
Middle Cerebral
Posterior cerebral.
A patient has dysarthria, speech impairment, facial paresis, and nausea. What part of the circulation is affected?
Posterior circulation - vertebral and basilar arteries. They may also have visual disturbance and altered consciousness.
Describe the acute management of stroke.
CT scan ASAP (act FAST - time is brain). Rule out haemorrhagic stroke.
Aspirin 300mg unless haemorrhagic
Thrombolysis eg streptokinase, 4.5 hours post-onset. Contraindications: recent surgery; brain aneurysm.
What is a lacunar stroke?
The most common type of stroke, resulting from occlusion of small penetrating arteries that supply the brain’s deep structures.
Give 3 risk factors for ischaemic and haemorrhagic stroke
85% ischaemic, 15% haemorrhagic.
Both: increasing age, hypertension, alcohol.
Ischaemic: Race, sex, TIA, diabetes
Haemorrhagic: Previous stroke, illicit drugs, anticoagulation therapy.
(PTS)
Describe the supportive management of stroke.
Nil by mouth due to aspiration risk.
IV hydration to decrease risk of cerebral oedema
Blood glucose 4-11mmol/L
Do not treat BP until a week after stroke.
Which arteries supply the cerebellum?
Anterior Inferior Cerebellar Artery, PICA and Superior Cerebellar Artery
What is a likely cause of sudden onset headache?
Subarachnoid haemorrhage. There is a ‘spider’ on the CT scan.
What is a TIA?
Transient ischaemic attack: the sudden onset of focal CNS phenomena due to temporary occlusion of part of the cerebral circulation. Symptoms last <24h. Often precede a first stroke.
(OHCM)
What is used to predict risk of stroke after a TIA and prompt referral?
ABCD2 score:
Age >60
BP >140/90
Clinical features - unilateral weakness (2 points), speech disturbance
Duration of symptoms - >1h 2 points; 10-59 min 1 point
Diabetes
Describe the secondary prevention of stroke.
Manage diabetes, HTN, AF.
Start statins 48h after stroke
Antiplatelet therapy- first aspirin then clopidogrel.
What are the surgical therapies for stroke?
Ischaemic - thrombectomy
Haemorrhagic - surgical evacuation of haematoma, endovascular coiling or clipping.
Describe the management of a TIA.
Assess risk of stroke using ABCD2. Control CVS risk factors - aim for <140/85mmHg, not 120/80; stop smoking; reduce BMI Antiplatelet therapy Warfarin indicated if cardiac emboli (OHCM)
Patient has weakness, sensory loss and visual disturbance lasting 30 minutes. What would this be apart from a TIA?
Hypoglycaemia
Migraine aura (symptoms spread and intensify over minutes)
Focal epilepsy (twitching and jerking)
Hyperventilation
What causes TIA?
Atherothromboembolism from the carotid is the main cause.
Cardioembolism (bilateral symptoms)
Hyperviscosity eg polycythaemia, sickle-cell anaemia, lymphocytosis.
(OHCM)
Describe the causes of intracranial haemorrhage.
Intracranial haemorrhage is bleeding inside the skull or brain. It can be due to a burst aneurysm. Hypertension and cardiovascular disease is therefore a major risk factor.
Define haemorrhage and haematoma.
Haemorrhage is bleeding from a blood vessel. Haematoma is collection of blood in the tissues, secondary to haemorrhage.
What can cause subarachnoid haemorrhage?
Berry aneurysm
Arteriovenous malformation (AVM) rupture
(PTS)
Traumatic - base of skull fracture, vertebral artery rupture (lecture 12.3.18)
What is Kernig’s sign and what 2 conditions can it indicate?
Meningitis, SAH
What is brudzinski’s sign and what 2 conditions can it indicate?
Meningitis, SAH
Describe the management of haemorrhage.
Manage risk factors - stop smoking, reduce BP, nimodipine reduces risk of cerebral ischaemia.
Give 3 complications of SAH.
Hydrocephalus
Cerebral ischaemia
Seizures
Describe the development of subdural haemorrhage.
- Bleeding from bridging veins (chronic or acute) causes decline in cognitive function.
- Days or weeks later, the haematoma starts to autolyse
- Increase in oncotic pressure sucks water into the haematoma
What causes subdural haemorrhage?
Head trauma Dementia or alcoholism; shaken babies; associated with small brain. Anticoagulation DM (PTS, lecture)
Define subarachnoid haemorrhage and describe the symptoms and signs.
Bleeding from circle of willis. Usually rapidly fatal. Sudden onset thunderclap headache, photophobia and reduced consciousness.
What causes superficial haemorrhages?
Severe contusion
What can cause deep haemorrhages?
Diffuse axonal injury.
What is an extradural haemorrhage?
Bleeding from middle meningeal artery, and dissection of the dura mater away from the skull. Haemotoma occurs slowly over a period of hours, with a period of compensation before a rapid rise in ICP.
Why is it important to monitor patients with suspected extradural haemorrhage?
There is a lucid period where the patient seems fine, but rapid rise in ICP can suddenly lead to loss of consciousness and death.
What is coning and what causes it?
ICP builds up, causing coning which is herniation of the brain through the foramen magnum. Usually fatal.
Describe the presentation of subdural haemorrhage
Loss of consciousness Seizure Nausea, vomiting Evolving neurological deficit. (PTS)
Describe the management of subdural haemorrhage.
1st line: Burr hole craniotomy - drainage to decompression
2nd line: Craniotomy - remove already formed clot.
(PTS)
What can cause extradural haemorrhage?
Head injury
Describe the management of extradural haemorrhage
Craniotomy: surgical decompression or drainage.
PTS
Give 2 symptoms of temporal arteritis.
(=GCA) Blurred vision, scalp tenderness
What should you do if you suspect temporal arteritis in a patient with visual disturbance?
Start steroids immediately because there is a risk of permanent vision loss.
How could a stroke cause left homonymous hemianopia?
If the stroke affects the right occipital lobe.
What can cause stroke?
Hypertension, berry aneurysms, trauma, anticoagulation, tumour, arteriovenous malformation.
Give 3 contraindications for thrombolysis
Haemorrhage, intracranial bleed, onset of symptoms over 4.5 hours ago or unknown, heparin, recent major surgery
(medsoc mock)
