Hemorrhagic CVA - Lecture 11 Flashcards
most common types
intracerebral hemorrhage
SAH
intracerebral hemorrhage is d/t
HTN or cerebral amyloid angiopathy (CAA)
what is CAA
harmless protein deposit that occurs with natural aging
SAH is d/t
ruptured saccular aneurysm or AVM
what else can hemorrhagic CVA be caused by
hyper anticoagulation
hemorrhage from brain tumor
trauma (such as TBI)
incidence (age)
low under age of 45
dramatically increases after 65
exponential with further aging
incidence (gender and race)
men > women
black > white
other risk factors
CAA induced changes in the blood vessel of the elderly
thrombolytic therapy
long term anticoagulation use
drug and alc abuse
pathogenesis
hyalinization of blood vessels
accumulation of fats and proteinaceous material
hyalinization of blood vessels
replace of smooth muscle cells by collagen
changes to the permeability of the vessel wall
hardening and calcification of vessel wall
loss of elasticity
accumulation of fats and proteinaceous material
leading to vessel walls that are prone to leak and rupture
onset of ICH
typified by gradual and steady evolution that occurs over minutes, hours and days
how many cases are sudden onset (ICH)
30%
when do hemorrhagic CVA occur
during physical activity in the daytime
how do hemorrhagic CVA present
severe HA
vomiting
seizures
ICH cuase
bleeding from an arterial source into the brain parenchyma
what are ICH often referred to as
intraparenchymal hemorrhage
ICH is
most fatal of all CVA subtypes
primary ICH is
spontaneous bleed
Primary ICH d/t
microvascular dz associated w/ HTN and/or aging
proposed scenario ICH
rupture of microaneurysms that burst as a result of HTN
what are most frequently involved (primary ICH)
small penetrating arteries
secondary ICH is NOT caused by
HTN
what are secondary ICH d/t
trauma
impaired coagulation
tumors
toxins
medical intervention ICH
lowering BP into normal range
treatment of edema
anticonvulsants
lowering BP into normal range via
antihypertension meds
treatment of edema
steroids
mannitol
glycerol-3
anticonvulsants
if seizures are present
what does an expanding lesion cause
significant increase in HTN
why can an expanding lesion be fatal
compression of vital centers
how does recovery occur
blood is reabsorbed before significant tissue destruction occurs
subarachnoid hemorrhage
WORST HEADACHE OF LIFE
WHOL
what is a SAH
hemorrhaging in the subarachnoid space
b/w arachnoid and pia mater
SAH accounts for
6-8% of all CVA
causes of SAH
trauma
non-traumatic causes
developmental defects
neoplasm
infection
spontaneous
non-traumatic causes
aneurysms and vascular malformations
spontaneous
occur in normotensive persons
aneurysms account for
90% of all SAHs
what is an aneurysm
abnormal distension of the blood vessels at bifurcations
caused by dz or weakening of the vessel walls
aneurysm stimulus
elevated BP
surgical interventions –>aneurysms
surgical clipping
endovascular coiling
surgical clipping
craniotomy
“clipping” at neck
endovascular coiling
catheter up femoral artery –> aorta –> aneurysm
platinum coils –> thrombotic reaction –> blocks flow and prevents rupture
most common sites of SAH
anterior communicating artery
posterior communicating artery
middle cerebral artery
dangers of SAH
spewing of blood, under high pressure, into brain tissue
susceptibility to re-rupture
obstruction of the SA space
blood in SA space
what can obstruction of SA space lead to
hydrocephalus d/t CSF blockage
blood in SA space
vasospasm
inflammatory and fibrotic responses in the meninges
vasospasm
resulting in ischemic infarction of the adjacent vessels
secondary complications often prove
fatal
what do SAH cause
extreme elevations in ICP
fatal brain herniation
extreme elevations in ICP d/t
obstruction of CSF and cerebral edema
fatal brain herniation d/t
increased pressure and mass within cranial cavity
primary sites of herniation
bones of the orbit and posterior fossa
SAH can be
mild to severe
mild SAH
often associated with stiff neck
mild HA
minimal focal neurologic signs
confusion lasting for weeks
moderate SAH
mild coma
moderate to severe HA
severe SAH
can be fatal
severe HA
decerebrate rigidity
deep coma
when is there significant chances of rebleeding
mod/severe
