WEEK 2: STROKE [Salonga] Flashcards
Stroke is
uncommon in people under 40 years; when it does occur, the
main cause is
High BP
Strokes are broadly categorized as
ischemic and hemorrhagic
Difference between ischemia and infarction?
Ischemia – reduction of blood flow for few seconds
Infarction – cessation of blood flow for a minutes
Neurologic sx resolve within 24hrs, No evidence of
brain infarct via imaging
TIA
Generalized ↓ cerebral blood flow d/t systemic
hypotension
syncope
widespread decrease in cerebral
blood flow that persists for longer duration + sx of brain
infarction
Global hypoxia-ischemia
ischemia/infarction of a small
area of the brain; usually caused by thrombosis (cerebral
vessels) or emboli (distant vessels)
infarction / focal ischemia
3 direct effects of hemorrhagic stroke that cause neuro sx?
Increased ICP
▪ mass effect on neural structures
▪ toxic effects of blood itself
supplies the medial surface of the frontal and parietal lobes and the corpus callosum.
ACA
supplies the Choroid plexus of the temporal horn of the lateral ventricle, hippocampus, amygdala, optic tract, lateral geniculate body, globus pallidus, and part of the posterior limb of the internal capsule
Anterior choroidal artery
Connects MCA to PCA
PCoA
supplies the:
o Lateral convexity of the cerebral hemisphere and insula.
o Trunk, arm, and face areas of the motor and sensory cortices
o Broca’s and Wernicke’s speech areas.
MCA
Lenticulostriate arteries are clinically relevant for what type of stroke?
Lacunar Stroke
what are the subdivisions of MCA?
M1 - horizontal segment
M2 - Sylvian segment
M3 - cortical segment
Supplies anterior 2/3 of the spinal cord
Anterior spinal artery
Formed by the confluence of the paired Vertebral arteries
Basilar artery
what arises from basilar artery? (4)
Pontine, AICA, SCA, PCA
supply corticospinal tracts and the intra-axial exiting fibers of the abducens nerve (CN VI).
pontine arteries
Supplies inferior surface of the cerebellum
AICA
supplies the superior surface of the cerebellum and the cerebellar nuclei.
o rostral and lateral pons, including the superior cerebellar peduncle and spinothalamic tract
Superior Cerebellar Artery
provides the major blood supply to the midbrain, occipital lobe, visual cortex
PCA
where does PICA arise?
PICA sa vertebral, pero AICA sa basilar
Supply of brainstem
pontine - from basilar
Ant Spinal Artery - Vertebral
Cerebrum, Cerebellum and Brainstem empty into
Dural venouis sinuses
Spinal cord venous drains in?
Internal and External Vertebral Plexuses
3 blood supply of the cerebellum?
SCA, AICA, PICA
receives most arachnoid granulations.
superior sagittal sinus
drains the superior surface of the cerebellum
straight sinus
due to occlusion of a cerebral blood vessel and causes cerebral infarction.
ischemic stroke
2 types of hemorrhagic strokes:
intracerebral hemorrhage
Subarachnoid hemorrhage
3 causes of cerebral infarction
- atherothrombotic cerebral infarction
- lacunar infarction
- cardiogenic cerebral embolism
etiology of ischemic stroke if large vessel, embolic
- The Heart
o Valve diseases, A. Fib, Dilated cardiomyopathy, Myxoma - Arterial Circulation (Artery to Artery Emboli)
o Atherosclerosis of carotid, Arterial dissection, Vasculitis - The Venous Circulation
o PFO w/R to L shunt, Emboli
etiology of ischemic stroke if large vessel, thrombotic
Virchow’s Triad 1. Blood vessel injury o HTN, Atherosclerosis, Vasculitis 2. Stasis/turbulent blood flow o Atherosclerosis, A. fib., Valve disorders 3. Hypercoagulable state o Increased number of platelets o Deficiency of anti-coagulation factors o Presence of pro-coagulation factors o Cancer
Risk factors for small vessels stroke
HPN – HLD – DM – Tobacco Use – Sleep apnea
lacunes are how many cm?
<1.5 cm
duration of transient neurologic symptoms
lasting less than 1 hour
TIA
Transient reduction of blood flow to a region in brain in the
absence of evidence of infarction on brain imaging
TIA
T or F? Significance of TIAs is increased risk of stroke after a TIA
specifically early on after a TIA
T
what are 2 cortical signs on (R) Brain?
Right gaze preference
Neglect
cortical left brain signs? (2)`
left gaze preference
aphasia
basta pag nasa cortex ang tingin ng mata nasa side ng lesion. pag infratentorial nasa opposite ng lesion
gyrus of brocas?
Left posterior inferior
frontal gyrus
gyrus of wernickes
Posterior part of the superior temporal gyrus
– Located on the dominant side
Small Vessel:
– No cortical signs on exam
t or F?
T
stroke syndrome that Rarely presents with an isolated symptom. Usually a combination of cranial nerve
abnormalities, and crossed motor/sensory
findings such as:
Brainstem stroke syndromes
Causes of hemorrhagic stroke?
Htn, aneurysm, trauma, tumor, AVM
“star shaped” lesion on CT
Sub arachnoid hemorrhage
Sudden onset, severe
headache (worst headache
of your life)
Sub arachnoid hemorrhage
From congenital aneurysms
of the Circle of Willis, less
commonly from AV
Malformations
Sub arachnoid hemorrhage
Rupture of thin walled
lenticulostriate arteries,
commonly seen in
hypertensives
intracerebral hemorrhage
typical sites of hypertensive ICH?
Basal Ganglia
– Cerebellum
– Pons
`Vomiting is more common
in IntraCerebellar Hemorrhage, SAH or
Ischemic CVA?
Intracerebellar
Pin-point but reactive pupils Abrupt onset of coma Decerebrate posturing or flaccidity Ataxic breathing pattern typical of?
Pontine hemorrhage
“Worst headache of my life” AMS Photophobia Nuchal rigidity Seizures Nausea and vomiting
typical of?
Subarachnoid hemorrhage
meaning of FAST in stroke eval?
Facial Drooping, Arm Weakness, Speech Difficulty, Time to call 911
give some diff dx to stroke?
Space occupying lesion (tumor, infection/ abscess, Epidural, Subdural Hematomas) • Subarachnoid hemorrhage • Seizures • Hypoglycemia • Migraine • Syncope • Labyrinthine disorders
what are some initial eval or diagnostics you can do in a stroke?
Cardiac monitoring, pulse-ox, ECG § Stat CT brain § c-xray § CBC, Platelet, PT, PTT § blood glucose, serum electrolytes § Cardiac markers, ABG’s § Blood alcohol level, Toxicology screen, Pregnancy test( as necessary)
remains
the gold standard as it is
superior for showing IVH
and ICH
non contrast CTH
Superior for showing
underlying structural lesions
MRi
primary objective in the management of stroke?
The primary objective is to restore adequate cerebral
perfusion to ensure adequate cerebral metabolism
and function:
1) Airway for adequate oxygenation
• 2) BP - maintain mean arterial pressure
• 3) Normal glucose level
• 4) Avoid hyperthermia
Goal in BP mx of stroke patients?
The goal is to maintain cerebral perfusion!!
formula of CPP?
CPP = MAP – ICP (needs to be at least 70)
difference in BP Goals in Ischemic vs Hemorrhagic
Higher BP goals with Ischemic stroke MAP 110-130 mm Hg
– Lower BP goals with Hemorrhagic stroke (avoid hemorrhagic
expansion, especially in AVMs and aneurysms) < 160 mmHg
systolic
T or F? Failure to recanalize (w/ or
w/o thrombolytic therapy)
results in high BP and poor
neuro outcomes
T
T or F? Infarction size and edema increase with acute and chronic
hyperglycemia
t
Hyperglycemia is an independent risk factor for hemorrhage when
stroke is treated with t-PA. T or F?
T
Seizures are common after hemorrhagic CVAs. T or F?
t
why is it important to treat fever in CVA?
because fever >24 hrs correlates with ventricular extension of the bleed
window when to give the IV tPA
3 to 4.5 hrs
Inclusion criteria for IV tPA?
§ Ischemic Stroke clinically § Persistent neurologic deficit beyond an isolated sensory deficit / ataxia § CT brain: No Blood § Initiation of Rx within 3 hours
exclusion criteria IV tPA?
Onset to treatment >3 hr (NINDS) § Rapid improvement § Blood on CT § Oral anticoagulant & PT>15 sec, INR>1.7 § Heparin (last 48 hr) & increased PTT § Platelet<100,000 § SBP>185 or DBP>110 § Aggressive treatment of b.p. § Stroke or head trauma (3 months) § Major surgery (2 wks) Prior ICH § GI tract/ Urinary bleed (14 d) § Seizure at onset § Signs & Sx’s of SAH § Non-compressible site of arterial puncture (7d)
if umabot ng 3 to 4.5 hrs, any exclusion criteria?>
Age >/= 80
Any use of anticoagulant regardless of the
PT/PTT
• NIHSS≥25
• Coexistent history of stroke and diabetes
mellitus
Management Post Thrombolysis
Admit to ICU
§ BP monitoring (Q 15 m x2 h, Q 30 m x6 h, Q 1 h
x16 h)
§ Treat SBP≥185 and DBP≥110
§ No anticoagulants, no anti-platelet for 1st 24 hr
post t-PA
Worsening of neurologic state—CT brain
§ ICH—Neurosurgery consult
§ Possible surgical intervention
§ Preferably: no foley or NG for 2 hr > t-PA
(t1/2-t-PA = 8-12 min)
What test?
Designed for acute stroke trials.
§ Quick (5-10 min) & reproducible.
§ Requires speech/language cards & safety pin.
§ Quantifies clinical stroke deficit:
NIH stroke scale
what NIH stroke scale has inc risk for ICH
> 22
what NIH Scale has poor prognosis if no treatment?
> 15
NIH stroke scale that is mild stroke?
<4
NIH score that will have will have an 80%
good or excellent outcome
12 to 14 and below
NIH Score of what will have less
than a 20% good or excellent
outcome
20-26
meaning of CADASIL?
Cerebral autosomal dominant arterof iopathy with subcortical
infarcts and leukoencephalopathy
mutation on CADASIL?
NOTCH 3 gene mutation on Ch 19
ICH total score?
6
ICH components on exam?
GCS IVH ICH Volume Infratentorial origin of ICH Age
NIHSS grading?
0 No stroke symptom 1 - 4 Mild 5 - 15 moderate 16 - 20 moderate to severe 21 - 42 severe stroke
triad of increased ICP:
headache, papilledema, vomiting
cushing’s triad
hypertension, bradypnea, bradycardia
