E3: acute adult neuro Flashcards
intracranial adaptive capacity
the ability of any of the 3 components of the brain to adapt to changes in size
increased intracranial pressure
increased pressure inside cranium, can lead to brain cell injury and death
brain cells are
voracious consumers of o2 and glucose
if the brain cells are deprived of o2 and glucose, what happens
irreversible damage in minutes
brain tissue %
80%
blood %
10%
CSF %
10%
cerebral perfusion pressure
required to perfuse brain cells
normal CPP
60-90 mm/hg
how much of the cardiac output does the brain require
15-20%
formula for CPP
CCP=MAP minus ICP
normal ICP
5-15 mm/Hg
etiology in increased ICP
- swelling of brain
- increased blood volume
- increased CSF
early clinical mani of increased ICP in LOC
confusion
restlessness
lethargy
late clinical mani of increased ICP in loc
loss of consciousness
early clinical mani of increased icp in pupil
subtle, sluggish reaction
late clinical mani of increased ICP in pupils
dialating, fixed
Cushing triad
late signs of VERY HIGH increased ICP
- widening pulse pressure (S increases, d decreases)
- bradycardia
- respirations decrease and are irregular
other signs of increased icp
- severe headache
- projectile vomiting
- seizures
- papilledema (edema of optic disc/nerve)
- altered motor function
(extremity strength and movement,
abnormal posturing
-decorticate
-decerebrate)
decorticate
abnormal flexion in increased ICP
decerebrate
abnormal extension in increased ICP
herniation of the brain
- sever increased ICP
- shifting of brain from one compartment to another
- places pressure on cerebral blood vessels and vital centers (medulla)
- death
traumatic brain injury (TBI)
damaged brain tissue swells
contrecoup
injury on opposite side of brain in TBI
front of head hits, slams against cranium (coup), then flies back and hits back of cranium (contrecoup)
types of skull fracture
- linear
- compound
- depressed
- basilar
what can happen with skull fracture
bleeding and CSF leak can happen
look for CSF out of the nose or ear
concussion
mild injury to head, reversible, some swelling
s/s of concussion
headache, confusion, difficulty concentrating
contusion
bruising of brain (worse than concussion)
s/s of contusion
same as concussion and may see s/s of increased ICP
epidural hematoma
- bleeding between skull and dura (furthest out)
- ARTERIAL bleed (meningeal artery)
- medical emergency
- bleeding compresses brain toward opposite side
subdural hematomas
- bleeding between dura and arachnoid matter
2. VENOUS bleed
s/s of subdural hematomas
same as increased ICP
types of subdural hematomas
- acute
- subacute
- chronic
acute subdural hematoma time
symptoms within 48 hrs
subacute subdural hematoma time
symptoms 2 days-2 weeks (slow bleed)
chronic subdural hematoma time
symptoms 2 weeks-several months (very slow bleed)
subarachnoid hemorrhage (SAH)
- bleeding into subarachnoid space
- ARTERIAL source
- poor prognosis
clinical mani of subarachnoid hemorrhage
- increased ICP
- blood mixing with CSG irritates meninges
- –nuchal rigidity (stiff neck)
- –photophobia (sensitivity to light)
- –diplopia (double vison)
brain tumors
- benign or malignant
- primary or metastasized (breast or lung)
- occupies space (increased ICP, necrosis)
clinical mani of brain tumors
- headache (early)
- seizures (early)
- increased ICP
intracerebral hemorrhage
- farthest IN all four types of bleed
- similar to SAH but further in
- usually produces a hemorrhagic stroke
- POOR PROGNOSIS
stroke etiology
rupture of cerebral artery or occlusion of cerebral artery
anoxia
lack of o2 and cerebral edema occurs in area of CVA
TIA
temporary interruption of arterial blood flow in the brain caused by platelet clumps
OR
blood vessel spasm
(little stroke, warns of stroke, s/s gone in 24 hrs)
risk factors for stroke
- hypertension
- heart failure
- hyperlipidemia
- diabetes
- smoking
- chronic A. fib without anticoag
- obesity
- physical inactivity
clinical mani of TIA
- blurred vision
- slurred speech
- weakness/numbness on one side of body
- decreased LOC
occlusive stroke
cerebral thrombosis
- mot common 85%
- atherosclerosis of artery causes occlusion (clot)
- leads to brain necrosis
- scar tissue remains
hemorrhagic stroke
- sudden onset
- blood vessels ruptures
- bleeding into cranium
- necrosis and scar tissue result
cerebral emoblus
- clot breaks loose (heart) travels to brain
- occludes cerebral artery
- causes tissue death
- onset is sudden
clinical mani of stroke
- headache
- dizziness
- confusion
- aphasia
- symptoms of increased ICP
- hemiparesis (paralysis) on opposite side of stroke
aphasia
change in speech- symptom of stroke
expressie aphasia
cant express self but can understand
receptive aphasia
cant receive messages
global aphasia
both expressive and receptive