A schematic diagram of CVA pathophysiology

1. SCHEMATIC PATHOPHYSIOLOGY
Predisposing Factors: Precipitating Factors:
1) Age ۞ 1) Hypertension ۞
2) Heredity ۞ 2) Cigarette Smoking
3) Race 3) Diabetes Meliitus ۞
4) Sex ۞ 4) Carotid or other Artery Disease ۞
5) Prior Stroke, TIA or heart attack ۞ 5) Atrial Fibrillation
6) Socioeconomic Factors ۞ 6) Other heart disease
7) Sickle cell disease
8) Undesirable levels of cholesterol
9) Poor diet ۞
10) Physical inactivity
11) Obesity
12) Alcohol Abuse
13) Drug Abuse
Atherosclerosis
Formation of Plaque deposits
Thrombosis
Hypertensio Occlusion by major vessel
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2. If managed: If not managed
Actual:
Possible:
Dx:
Dx: PET scan, MRI,
Lysed or moved thrombus
Cranial CT scan (6/16/08)
cerebral angiography,
from the vessel
Capsuloganglionic bleed
lumbar puncture, EEG/
Lacunar infarct,
ECG, skull x-ray,
Bilateral Internal Carotid
carotid ultrasonography
Ateriosclerosis
Vascular wall becomes
Doppler (6/16/08)
TX: aspirin within 24 weakened and fragile
Mean flow velocities and
hrs, thrombolytics within
pulsatility index of both
3 hours, carotid
anterior and posterior
stenting, hypothermia,
circulation within normal Leaking of blood from the
anticoagulants, surgical
limits fragile vessel wall
decompression
(hemicraniectomy),
EEG/ECG, skull x-ray,
carotid endartectomy
carotid ultrasonography
Guarded Prognosis
Cerebral Hemorrhage
Sx:, headache,
unconsciousness,
If managed: If not managed nausea/vomiting,
Dx: CT scan, MRI, cerebral angiography, visual disturbances
arteriography,
lumbar puncture, skull x-ray
Tx: chronic hypertensives, surgical
decompression, evacuation and aspiration,
administration of fresh frozen plasma with
Mass of blood forms and
fibrinogen or cryoprecipitate
grows
Decreased
Hematoma evacuation
ICP
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Formation of cavity surrounded by dense gliosis

3. > 60 ml
< 30 ml 30-60 ml
hemorrhage
hemorrhage hemorrhage
Intermediate Poor prognosis
Good prognosis
prognosis
Vasospasm of
tissue and arteries
Blood seeps into the Formation of small
ventricles and large clots
CEREBRAL
HYPOPERFUSION
Sx: dizziness,
Obstruction of CSF
confusion,
passageway
headache Impaired distribution of
oxygen and glucose
Accumulation of CSF in
the ventricles
Tissue hypoxia and
cellular starvation
Ventricles dilate behind
Lodges unto
the point of obstruction
Cerebral Ischemia
other cerebral
arteries
Increased ICP
Initiation of ischemic
cascade
If not managed
If managed:
Ventriculostomy,
VP shunt, ICP Anaerobic metabolism by
Monitoring mitochondria
Alternative route Unrelieved
Production of oxygen free
for return of CSF obstruction
radicals and other reactive
in the circulation Generates large amounts of Failure production of oxygen species
lactic acid adenosine triphosphatase
Compression of
Guarded
brain tissues will Failure of energy dependent
Metabolic Acidosis
Prognosis
not occur process
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(ion pumping)

4. Release of excitatory Damage to the blood vessel
neurotransmitter glutamate endothelium
Influx of calcium
Failure of
Activates enzymes that
mitochondria
digest cell proteins, lipids
and nuclear material
Further energy
depletion
Transient Ischemic Attack
If not managed
If managed:
-t-PA (urokinase,
streptokinase)
Brain sustains an irreversible
-calcium channel
cerebral damage
blockers
Release of metalloprotrease
(zinc and calcium-dependent enzymes)
Guarded
Prognosis
Break down of collagen, hyaluronic acid and
other elements of connective tissue
Structural integrity loss of brain
tissue and blood vessels
Breakdown of the protective
Blood Brain Barrier
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5. Cerebral edema
Vascular Congestion
Compression of tissue
Increased intracranial
pressure
Impaired perfusion and
function
Middle Anterior cerebral Posterior CerebraI Internal Carotid Vertebrobasilar Anteroinferior Posteroinferior
Cerebral Artery artery Artery Artery System Cerebellar cerebellar
Lateral Frontal Lobe Occipital lobe; Branches into Cerebellum and Cerebellum Cerebellum
hemisphere, anterior and ophthalmic, PCA, brain stem
frontal, parietal medial portion of anterior choroidal,
and temporal temporal lobe ACA, MCA
lobes, basal
ganglia
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6. Sx:
Sx:
Sx: Sx: Sx:
Sx:
Sx: Ipsilateral
contralateral
Contralateral Contralateral Mild
Ataxia,
Alternating ataxia, facial
hemiparesis
hemiparesis or hemiparesis, contralateral
paralysis of the
motor paralysis,
with facial
hemiplegia, foot and leg hemiparesis,
larynx and soft
weaknesses, ipsilateral loss
asymmetry,
unilateral deficits greater intention
palate,
ataxic gait, of sensation in
contralateral
neglect, altered than the arm, tremor, diffuse
ipsilateral loss
dysmetria, face, sensation
sensory
consciousness foot drop, gait sensory loss,
of sensation in
contralateral changes on
alterations,
, homonymous disturbances, pupillary
face,
hemisensory trunk and
homonymous
hemianopsia, contralateral dysfunction,
contralateral on
impairments, limbs,
hemianopsia,
inability to turn hemisensory loss of
body,
double vision, nystagmus,
ipsilateral
eyes toward alterations, conjugate
nystagmus,
homonymous Horner’s
periods of
affected side, deviation of gaze,
dysarthria,
hemianopsia, syndrome,
blindness,
vision changes, eyes toward nystagmus,
Horner’s
nystagmus, tinnitus,
aphasia if
dyslexia, affected side, loss of depth
syndrome,
conjugate hearing loss
dominant
dysgraphia, expressive perception,
hiccups and
gaze, paralysis,
hemisphere is
aphasia, aphasia, cortical
coughing,
dysarthria,
involved, Mild
agnosia, confusion, blindness,
vertigo, nausea
memory loss,
Horner’s
memory deficits, amnesia, flat homonymous
and vomiting
disorientation,
syndrome,
vomiting affect, apathy, hemianopsia,
drop attacks,
carotid bruits
shortened perseveration,
tinnitus,
attention span, dyslexia,
hearing loss,
loss of mental memory
vertigo,
acuity, apraxia, deficits, visual
dysphagia,
incontinence hallucinations
coma
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7. If not managed:
If managed:
Palliative care-
Frequent vital sign and
neurovital signs,
intubation, mechanical
Continued insufficiency of blood
ventilation, vasodilators,
osmotic diuretics, flow
ventriculostomy, ICP
monitoring
Further compression of tissues
Poor cerebral perfusion
Coma
Poor improvement
Cerebral Death
Poor
Prognosis
Loss of neural feedback
mechanisms
Cessation of physiologic
functions
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8. Pulmonary Other systems
GUT
Cardiovascular GIT
System
System
Relaxation of
Sx: restlessness,
intestines and
Loss of cardiac Relaxation of abnormal
sphincters thermoregulation,
muscle function venous valves
mental confusion,
increased secretions,
decreased urinary
output.
Sx: Sx:
bradycardi hypotension
Loss of bowel
Failure of accessory Loss of lung control
Decreased muscles for breathing movement
Neurogenic bladder Loss of sphincter
cardiac output
control
Sx:
apnea
Cardiopulmonary arrest
Systemic Failure
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DEATH