stroke Flashcards
definition of stroke?
stroke is a focal neurological deficit due to a vascular lesion.
cerebrovascular disease present as?
acute hemorrhage and gradual cerebral ischemia
most common incidence of stroke?
cerebral infarction
risk factors of stroke?
non modifiable: age, gender(m>f), hereditary, previous vascular event MI and peripheral embolism.
modifiable: HTN, hyperlipidemia, DM heart failure, atrial fibrillation, high alcohol, oral contraceptives, smoking, polycythemia.
pathophysiology of stroke?
ischemic: thrombosis, embolism
hemorrhagic: rapture of blood vessels.
intracerebral hemorrhage occur at which sites?
cerebellum, pons, internal capsule
causes of ischemic stroke?
atherosclerosis, vasculitis(temporal arteritis, polyarteritis nodosa, polycythemia, DIC ,arterial dissection, cocaine and amphetamine.
embolism from cardiac sources mitral stenosis
atheroembolic source, hypercoagulable states form thrombus( deficiency of factor S, C and antithrombin 3
causes of hemorrhagic stroke?
HTN, rapture cerebral aneurysm, raptured AV malformation, bleeding disorder, anticoagulant therapy, trauma, amyloid angiopathy(age related) cocaine and amphetamine abuse
blood supply of brain?
2 internal carotid
2 vertebral
>internal carotid give: anterior(portions of motor and sensory of leg and bladder, inhibitory micturition center) and middle cerebral arteries( motor and sensory of face hand and arm, broca’s and wernicks area visual cortex and basal ganglia
>vertebrobasilar( brainstem, thalamus, posterial 2/5 of cerebrum.
clinical classification of stroke?
TIA: symptoms remains less than 24 hr
evolving stroke: stepwise increase in focal neurological deficit from hours to days
complete stroke: when symptoms persist for more than 24 hr.
features of internal carotid TIA?
weakness of contralateral side of body, numbness or paresthesia may also occur as sole representation, aphasia, amaurosis fugax.
features of vertebrobasilar TIA?
vertigo, ataxia, diplopia ,dysarthria, dimness, blurring of vision, drop attack due to bilateral leg weakness
D/D of TIA?
focal epilepsy(jerking of limbs not in TIA) migraine( headache and visual disturbance not in TIA)
investigations?
Blood cp, FBS. serum cholesterol, ECG, X-ray chest, echo, blood culture, carotid doppler, CT/MRI on urgent basis to differentiate infarction and hemorrhage.
treatment?
Medical treatment:
Tissue plasminogen activator if present less than 4.5 hour of symptoms appear then aspirin
embolization from carotids: aspirin 300mg daily or clopidogrel 75mg or dipyridamole 200mg
embolization from heart: anticoagulant heparin followed by warfarin if they not suited then anti-platelet aggregation aspirin 300mg/day
surgical include angioplasty by stent or carotid endarterectomy if 70-99% stenosd
treatment for TIA according to NSF?
antiplatelet, anticoagulation, statins, carotid surgery.
D/D of evolving stroke?
subdural hematoma, cerebral tumor
difference between TIA and stroke?
in TIA symptoms don’t lasting long
most common type of stroke?
hemiplegic infarction of internal capsule
why middle cerebral artery is more affected by emobolism?
emboli from heart and carotid enter into large caliber middle cerebral artery than anterior cerebral artery secondly colateral from anterior communicating arteries prevent ischemia
conciousness is altered in which artery involved?
vertebrobasilar
when coma occur in stroke?
when infarction of brainstem involved reticular formation
which type of aneurysm raptured in hypertensive patient?
charcot-bouchard aneurysms
clinical features of hemorrhagic stroke?
abrupt onset of headache with focal neurological deficit worsen over 30-90 min
surgical evacuation of hematoma?
not helpful except in cerebral hematoma
medical management of hemorrhagic stroke?
Airway protection if gcs<8 Head elevated 30-45 Reverese coagulopathy with vit k and ffp Platelet transfused if expanding ICH mannitol to reduce ICP blood pressure control <160-140 nursing Surgical management: decompression hemicraniectomy
findings of CSF after several hours of subarachnoid hemorrhage?
yellow color csf xanthochromic
What is locked in syndrome?
Basilar or vertebral artery occlusion Progressive awake quadriplegia Bilateral facial and oropharyngeal palsy Preserve cortical function and vertical gaze Patient is awake until ras involved
Pica?walenburg syndrome
Vertigo, comiting, nystagmus, contralateral sensory loss
Ipsilateral horner syndrome
Dysphagia and dysarthria
Ipsilateral ataxia
Most common site of hemorrahgic stroke?
Putamen, then thalamus pons and cerebral hemisphere
Most common type of SAH?
Saccular berry aneurysm( junction of anterior cerebral artery with anterior communicating artery
What if ct scan is negative in SAH?
Lumber puncture xanthochromic csf from rbc breakdown)
Difference of Lp of meningitis and SAH?
In meningitis wbc:rbcs ratio increases
In SAH: normal
Normal: 1wbc per 500-1000 rbcs
Treatment of SAH?
CCB nifidipine to prevent vasospam
Siezure prophyalix
Surgixal clipping
Surgical coiling is prefer now
