Stroke Flashcards
2 main types of stroke
ischaemic 85% (TIA if <24hr, ischaemic stroke if >24hr)
haemorrhagic 15%
subtypes of ischaemic stroke?
thrombotic
embolic (AF big risk factor)
subtypes of haemorrhagic stroke?
intracerebral haemorrhage
SAH
risk factors for
1) ischaemic
2) haemorrhagic
stroke
1) cardiovascular: age, hypertension, smoking, hyperlipidaemia, DM
2) age, hypertension, AVM, anticoagulation therapy
what is stroke (WHO defintion)
rapidly developing clinical signs of focal (at times global) disturbance of cerebral function, lasting more than 24 hours or leading to death with no apparent cause other than that of vascular origin
symptoms of a cerebral hemisphere infarct?
contralateral hemiplegia (flaccid then spastic)
contralateral sensory loss
homonymous hemianopia
dysphasia
symptoms of brainstem infarction?
may have more severe symptoms including quadriplegia and lock-in syndrome
what are lacunar infarcts?
small infarcts around the basal ganglia, internal capsule, thalamus and pons
symptoms of lacunar infarcts?
pure motor, pure sensory, mixed motor and sensory signs or ataxia
what 3 criteria is the oxford stroke classification system based on?
1) hemiplegia or hemi-sensory loss in face, arm and leg
2) homonymous hemianopia
3) high cognitive deficit e.g. aphasia
what 3 criteria is the oxford stroke classification system based on?
1) unilateral hemiparesis and/or hemisensory loss of the face, arm & leg
2) homonymous hemianopia
3) higher cognitive deficit e.g. dyphasia
Total anterior circulation infacts (TACI)
1) involves which cerebral arteries
2) which oxford stroke classification criteria are present?
1) middle and anterior
2) all 3
Partial anterior circulation infacts (PACI)
1) involves which cerebral arteries
2) which oxford stroke classification criteria are present?
1) small arteries of anterior circulation e.g. upper or lower division of MCA
2) just 2
.
.
Lacunar infarcts (LACI)
1) involves which cerebral arteries
2) presents how?
1) perforating arteries around internal capsule, thalamus and basal ganglia
2) 1 of:
- unilateral weakness (and/or sensory deficit) of face and arm, arm and leg or all three.
- pure sensory stroke
- ataxic hemiparesis
Posterior circulation infarcts (POCI)
1) involves which cerebral arteries
2) which oxford stroke classification criteria are present?
1) vertebrobasilar arteries
2) 1 of:
- cerebellar or brainstem syndromes
- LOC
- Isolated homonymous hemianopia
Whilst symptoms alone cannot be used to differentiate haemorrhagic from ischaemic strokes, patients who’ve suffered haemorrhages are more likely to have:
decreased LOC
HA, N&V, seizure
why is neuroimaging urgently indicated in stroke?
to classify as either ischaemic or haemorrhagic and thereby determine whether thrombolysis can be done
what is the criteria for offering thrombolysis in stroke?
must administer within 4.5hrs of onset of symptoms
haemorrhage has been definitively excluded (i.e. imaging)
once haemorrhagic stroke has been excluded patients should be given what medication?
300mg aspirin
immediate management of TIA?
aspirin 300mg (unless contraindicated)
referral pathway
1) if patient has had suspected TIA in last 7 days
2) if patient has had suspected ITA more than 1 week previously
1) urgent assessment within 24hr by stroke specialist
2) urgent specialist assessment within 7 days
T/F: the vast majority of patients with haemorrhagic stroke will undergo surgical intervention
false - most not suitable for surgical intervention
management of haemorrhagic stroke?
supportive
- stop anticoagulants and antithrombotics e.g. clopidogrel
- reverse anticoagulation asap
what is the ROSIER score used for?
to identify symptoms of stroke (exclude hypoglycaemia first)
if >0, stroke is likely
1st line radiological investigation for suspected stroke?
non-contrast CT head
immediate management of acute stroke?
aspirin 300mg PO/ PR asap once haemorrhagic stroke excluded
T/F: AF should be immediately treated with anticoagulants if identified in a stroke patient
False- anticoagulants should not be started until brain imaging has excluded haemorrhage, and usually not until 14 days have passed from the onset of an ischaemic stroke
thrombolysis agent?
alteplase
absolute contraindications to thrombolysis?
previous haemorrhagic stroke
absolute contraindications to thrombolysis?
- Previous IC haemorrhage
- Seizure at onset of stroke
- Intracranial neoplasm
- Suspected SAH
- Stroke/ traumatic brain injury in preceding 3 months
- LP in past 7 days
- GI haemorrhage in preceding 3 weeks
- Active bleeding
- Pregnancy
- Oesophageal varices
- Uncontrolled hypertension >200/120mmHg
Offer thrombectomy as soon as possible and within ___ hours of symptom onset, together with ?what?, to people who have: acute ischaemic stroke and confirmed occlusion of the __ __ circulation demonstrated by what imaging
6
IV alteplase (if <4.5 hr)
anterior cerebral
CT/ MR-angiogram
(can be up to 24 hours if imaging shows potential to salvage brain tissue e.g. limited infarct core volume)
Offer thrombectomy as soon as possible and within ___ hours of symptom onset, together with ?what?, to people who have: acute ischaemic stroke and confirmed occlusion of the __ __ circulation demonstrated by what imaging
6
IV thrombolysis (if <4.5 hr)
proximal anterior
CTA/ MRA
(can be up to 24 hours if imaging shows potential to salvage brain tissue e.g. limited infarct core volume)
secondary prevention post stroke?
clopidogrel first line
aspirin + MR dipyridamole if clopidogrel not tolerated
T/F: hypertensives should be routinely used post stroke
false - only in those with HTN
T/F: hypertensives should be routinely used post stroke
only if there is a hypertensive emergency: Hypertensive encephalopathy Hypertensive nephropathy Hypertensive HF/ MI Aortic dissection Pre-eclampsia/eclampsia
T/F: all stroke patients should be started on a statin
False- only if cholesterol is > 3.5 mmol/l
Many physicians will delay treatment until 48 hr due to the risk of haemorrhagic transformation
what is Wallenberg’s syndrome?
aka lateral medullary syndrome
ipsilateral: ataxia, nystagmus, dysphagia, facial numbness, cranial nerve palsy e.g. Horner’s
contralateral: limb sensory loss
what is Weber’s syndrome?
ipsilateral CN III palsy contralateral weakness (upper and lower limbs)
effects of a stroke affecting anterior cerebral artery?
contralateral hemiparesis and sensory loss
lower limb > upper
effects of a stroke affecting middle cerebral artery?
contralateral hemiparesis and sensory loss
upper limb > lower
contralateral homonymous hemianopia
aphasia
effects of a stroke affecting posterior cerebral artery?
contralateral homonymous hemianopia with macular sparing
visual agnosia
what arteries are affected in weber’s syndrome?
branches of the posterior cerebral artery that supply the midbrain
which vessels are affected in Wallenberg syndrome?
posterior inferior cerebellar artery
what kind of visual loss is associated with retinal/ ophthalmic artery occlusion?
Amaurosis fugax
a lesion in the __ artery can lead to ‘locked in’ syndrome
basilar
T/F: lacunar strokes have a strong association with hypertension
true
stroke of ACA affects ___
stroke of MCA affects ____
stroke of PCA affects ____
leg
face
vision/ arm
