STROKE + SAH Flashcards
What are the types of haemorrhagic stroke? What percentage of strokes are they?
Due to rupture of BV within the brain.
2/3 SAH
1/3 intra cerebral dt HTN
What is a stroke? What is a TIA?
A stroke is focal neurological deficit that lasts for greater than 24 hours.
TIA < 24 hours
What are the types of ischemic stroke? What percentage of strokes are they?
85%
Usually due to:
- thrombosis
- emboli
- global ischemia
When would you consider haematological causes? What are the causes?
Patients < 45
Cryptogenic stroke (unknown cause)
Hx of hypercoagulable state
Causes: Myeloproliferative - polycythemia Vera - essential thrombocytosis Hypercoagulable state Thrombocytopenia with thrombosis Sickle cell anemia
What are potential sources of emboli?
Cardiogenic Rhythmic - AF - SSS - sustained atrial flutter
Valvular
- RHD: mitral/aortic
- prosthetic
- IE
- fibrous endocarditis e.g. SLE
Myocardium
- mural thrombus
- MI
- CHF with EF < 30%
- dilated cardiomyopathy
Non-cardiogenic
- atherosclerotic emboli
- fat emboli
- air emboli (iatrogenic)
Causes of ICH?
HTN Trauma Bleeding diatheses Amyloid angiopathy Illicit drugs: amphetamines, cocaine
Causes of SAH?
Ruptured berry aneurysm
Vascular malformation (AVM)
Trauma
Risk factors for stroke?
FHx Cerebral - cerebrovascular disease - berry aneurysm CVS - HTN - smoking (X2) - hyperlipidaemia - AF - MI - IHD Haematological - hypercoagulable state - polycythemia - warfarin (haemorrhage) - thrombolysis
S + S of stroke?
Focal neurological deficit - hemiparesis - aphasia - loss of vision - dysphagia - dizziness, loss of balance HEADACHE SEIZURES (in haemorrhagic)
If sudden onset focal deficit, what are you thinking? If deficit goes hours - days?
Sudden LOC without focal neurological deficit.
Embolism
ICH
Small vessel disease
Potential SAH
If a stroke causes purely motor think? If pure sensory think? If hand only?
Internal capsule or pons
Thalamus
Cortex or peripheral neuropathy
If isolated ACA?
If MCA?
If PCA?
ACA - contralateral hemiparesis + sensory loss, mostly in leg
MCA - contralateral weakness + sensory loss of face and arm while sparing arm.
- homonymous hemianopia ipsilateral
- if superior branch -> broca’s
- if inferior branch -> wernickes
PCA
- contralateral homonymous hemianopia
- superior quadrantopia
- memory impairment
What is a lacunar INFARCT? What are features?
Occlusion in one penetrating artery.
Pure motor stroke/hemiparesis (posterior limbinternal capsule)
Pure sensory loss (thalamus)
Ataxic hemiparesis (ant. Limb of internal capsule)
Dysarthria - clumsy hand
Mixed sensorimotor - thalamus and posterior internal capsule
What LAB investigations?
CBE EUC LFT CRP BGL URINALYSIS
COAGS: INR if warfarin, PT
Radiological Ix acutely?
Non contrast CT head: ischemic vs haemorrhagic
- looking for SAH vs ICH
- ischemic may show up later than 3-24 hours after deficit
Head MRI if brainstem/cerebral stroke suspected
If CT normal but high suspicion of SAH -> lumbar puncture
To determine cause later Ix?
Ischemic
- ECG for MI
- echo for valvular disease
- carotid US
Haemorrhagic
- cerebral angiography to identify source of SAH
How do you diagnose strokes?
Clinically
If TIA do ABCD2 for risk of future stroke over next 7 days.
Management for ischemic stroke?
Thrombolysis within 4.5 hours
Aspirin within 48 hours
Hemicraniectomy if massive stroke and <60 years
Admit to stroke unit
Control
- BP
- fever
- Glucose
Contraindications to thrombolysis?
Active bleeding Haemorrhagic stroke Recent head trauma History of intracranial haemorrhage BP high unresponsive to medication
What do you do acutely if thrombolysis contraindicated?
Aspirin (rule out haemorrhagic)
If aspirin contraindicated -> clopidogrel
Control
- Sa02
- BP
- fever
- BGL
VTE prophylaxis
Long term management of ischemic stroke?
Secondary prevention by Treat rf Anti platelet therapy if ischemic -> clopidogrel or (aspirin + dipyridamole) Educate Allied health Rehab
Management of haemorrhagic stroke?
Prevention mainstay
Clip aneurysm
Treat complications
Nimlodopine
