Stroke Flashcards
What is the definition of stroke?
An acute onset of focal neurological signs/symptoms due to an interruption in the blood supply
What are TIA’s?
Transient ischaemic attacks are sometimes defined as being <24hours of symptoms with complete resolution
What % of TIA’s can show damage on MRI?
50%
2 main subtypes of stroke?
Ischaemic stroke (85% of cases)
Hemorrhagic stroke (15% of cases)
What is ischaemic stroke?
Blood clot stopping blood to an area of the brain.
What is hemorrhagic stroke?
Most common type is intracerebral haemorrhage. In this the weakened/diseased vessels rupture.
Stroke is the 3rd most common cause of mortality in Scotland. True/false?
True
Some risk factors of stroke?
High systolic blood pressure
High BMI
High fasting blood glucose
Smoking
High diet sodium
High LDL cholesterol
What is total anterior circulation syndrome (TACS)?
A large cortical stroke affecting the areas of the brain supplied by both the middle and anterior cerebral arteries.
TACS features?
Hemiplegia involving at least 2 out of face, arm and leg +/- hemisensory loss.
Homonymous hemianopia
Cortical signs e.g. dysphasia
What is partial anterior circulation syndrome (PACS)?
A less severe form of TACS, where only part of the anterior circulation has been compromised.
PACS features?
Hemiparesis (same conditions as TACS - with only partial weakness).
Monoparesis
Homonymous hemianopia
Any 2 of the 3 shown above.
What is Lacunar syndrome (LACS)?
Clinical manifestation of lacunar infarctions. Lacunar infarctions are small infarcts in the deeper parts of the brain (basal ganglia, thalamus, white matter) and in the brainstem.
Cause of lacunar syndrome?
Occlusion of a single petetrating artery. Motor or sensory or both affecting 2 of the face, arm and leg.
What is the prognosis for LACS?
Has the best prognosis of all strokes with 60% of patients and alive and independent in 1 year.
What is posterior circulation syndrome (POCS)?
Occurs in the arteries that supply blood to the back of the brain.
Some features of POCS?
Cranial nerve palsies
Cortical blindness
Cerebellar defects +/- motor sensory signs
What is cortical blindness?
Loss of vision without any ophthalmological causes and with normal pupillary light reflexes due to bilateral lesions of the striate cortex in the occipital lobes.
2 main subtypes of hemorrhagic stroke?
Intracerebral haemorrhage an subarachnoid haemorrhage
Ischaemic cascade definition?
A series of biochemical reactions that are initiated in the brain and other aerobic tissues after seconds to minutes of ischaemia.
Ischaemia core definition?
An area of the brain which has developed necrosis. Cerebral blood flow < 20%
Ischaemic Penumbra meaning?
Area of the brain with reduced cerebral blood flow, but also getting supply of oxygen and glucose from collateral arteries.
If brain tissue is reperfused after ischaemia, there is no chance it could be salvaged. True/false
False, there is still possibility it can be recovered.
What is TOAST?
System used to classify ischaemic stroke based on the cause.
5 subtypes of ischaemic stroke for TOAST?
1) Large artery atherosclerosis
2) Cardioembolism
3) Small-vessel occlusion
4) Stroke of determined aetiology
5) Stroke of undetermined aetiology
What is the best time for evaluating and treating acute stroke?
60 mins or less
Key questions to confirm stroke?
Is it a stroke? - Clinical diagnosis
What type of stroke? - CT (or MRI) imaging
Is there a large vessel occlusion? - CT or MR angiogram
What is thrombolysis?
The lysis (breakdown) of a clot by tissue plasminogen activator (usually alteplase).
Aim to restore flow and save prenumbra
What indications would patient need for thrombolysis?
Decision is based on balance between the risk and benefits:
- Potential benefit gained from thrombolysis
- Blood pressure (ideally <185/110mmHg)
Contra-indication examples for thrombolysis?
- On anticoagulant
- Previous intracerebral haemorrhage
- Recent stroke
- Seizure
- Severe hypertension (can be treated first)
- Recent head injury
- Pregnancy/post-partum
- NOT AGE!!!!!
2 complications of thrombolysis?
- Haemorrhage
- Anaphylaxis
What is thrombectomy?
Surgery to remove a blood clot from inside an artery or vein.
Who is the target patients for thrombectomy?
- Ischaemic stroke patients
- Have a large vessel occlusion
~ Carotid artery
~ Middle cerebral artery
~ Basilar artery - If patient has salvageable brain tissue
What is the ASPECTS score?
- Can be scored up to 10
- A normal brain has a score of 10 and as more areas of the brain are affected, the score falls.
What 10 areas are monitored by the ASPECTS score?
- Anterior circulation
- Posterior circulation
- Caudate = a paired, “C”-shaped subcortical structure which lies deep inside the brain near the thalamus.
- Lentiform = a lens-shaped, bilateral structure in the basal ganglia bounded by the internal and external capsules.
- Internal capsule
- Insular ribbon
- MCA (middle cerebral artery)
- M1 to M6 (territories of the MCA cortex)
List some complications for the acute phase of stroke?
Malignant MCA (middle cerebral artery) syndrome
Aspiration pneumonia
DVT/PE
Dehydration/electrolyte impairment/AKi (acute kidney injury)
What is malignant MCA syndrome?
- Rare syndrome usually seen in large anterior territory stroke (<10% of ischemia stroke patients).
- Tends to occur 2-5 days after stroke but can be <24hrs.
- Generally problematic in younger patients.
- Approx 80% mortality
- Treatment is with hemicraniectomy
~ Improves survival and possible disability in younger patients.
~ May be left with significant disability.
What is a hemicraniectomy?
A surgical procedure where a large flap of the skull is removed and the dura is opened to relieve the pressure from the swollen, infarcted brain tissue, preventing brain herniation and death.
Why is a hemicraniectomy useful?
Improves the survival and possible disability in younger patients.
Secondary prevention in stroke?
Immediate management
Long term management
Antiplatelets
BP management
Anticoagulation
Cholesterol reduction
When is BP management advised in stroke settings?
In order to carry out safe thrombolysis
Options for lowering blood pressure in stroke setting?
IV labetalol (beta blocker) and IV GTN
When are anti-platelets used for ischaemic stroke and TIA’s?
Immediate management - in all strokes and TIA’s.
Long term - small vessel atheromatous disease and large vessel atheromatous disease.
Which antiplatelets are used depending on NIHSS score?
Dependent on NIHSS score (stroke severity):
- If NIHSS < 4 = aspirin 300mg stat + clopidogrel 300mg stat followed by 75mg daily of each for 3 weeks with daily 75mg clopidogrel to continue for life
- If stroke is more severe = aspirin 300mg stat + 300mg daily followed by daily 75mg clopidogrel after 2 weeks.
What is done in the case of recurrent strokes/TIA’s?
Requires further investigations to assess whether the cause is:
- Cardioembolic
- Hypoperfusion
- Other pathology i.e. seizures
If still due to atherosclerotic disease - consider genetic testing for clopidogrel resistance.
Which types of strokes have the worst prognosis?
Anterior circulation strokes.
Total anterior stroke = 60% dead at 1 year
Partial anterior stroke = 19% dead at 1 year.
Lacunar strokes and posterior circulation strokes have the better prognosis.
What barriers can be present during patient rehabilitation?
Cognition
Communication and language
Plateau of function
Complications
Incontinence
Depression
Pain
What is an Intracerebral haematoma?
A subtype of stroke, is a devastating condition whereby a hematoma is formed within the brain parenchyma with or without blood extension into the ventricles.
Some causes of ICH?
- Vascular abnormality: aneurysm, AVM, cavernoma, venous sinus thrombosis (Hypertensive), Haemorrhagic stroke
- Infection
- Trauma
- Amyloid (deposition of amyloid protein)
- Iatrogenic
- Neoplastic/Tumour (melanoma, renal, choriocarcinoma, papillary thyroid)
Management of ICH?
Neurology/ Stroke
Neuroradiology
Neurosurgery
OT/PT
Neurorehab
Presentation of ICH?
Vascular abnormality:
- Aneurysm: sudden onset headache, photophobia, neck stiffness
- AVM: seizure
- Cavernoma: seizure
venous sinus thrombosis : headache, visual disturbance
- (Hypertensive) : hypertension
- Haemorrhagic stroke: stroke presentation
Infection: temperature, neck stiffness, photophobia, known infective focus
Trauma: external signs of trauma
Amyloid: demographics
Metabolic? Signs of Liver cirrhosis (jaundice, spider naevi, ascites)
Iatrogenic
Neoplastic/Tumour: seizure, deficit, high ICP features (early morning headache)
General: headache, reduced GCS, focal deficit, seizure
Investigations for ICH?
CTA (CT angiography)
DSA (digital subtraction angiography)
What arteries supply the cerebral vascular territories of the brain?
Anterior cerebral artery (supplies front of the brain)
Medial lenticulate arteries (area behind the ACA)
Middle cerebral artery (supplies lateral areas of brain)
Anterior choroidal artery
lateral lenticulostriate arteries
Posterior cerebelar artery (PCA)
Superior cerebelar artery (SCA)
What is the treatment of ICH based on?
Site
Size
Underlying cause
Clinical picture
Age, comorbidities
Difference between intracerebral vs intracranial?
Intracerebral is occurring in the brain parenchyma as for intracranial means occurring within the skull generally.
Difference between DSA and CTA?
DSA procedure involves inserting a catheter (a small, thin tube) into an artery in the leg and passing it up to the blood vessels in the brain.
CTA carries less of a risk for developing neurological complications compared with DSA because of the minimally invasive nature of the procedure.
