NEURO Flashcards
what is CN I and it’s function?
olfactory; smell
what is CN II and it’s function?
optic; sight, NOT pupil rxn
what is CN III and it’s function?
oculomotor; pupillary function
increased ICP parasympathetic stimulation (constriction) is blocked, sympathetic stimulation predominates = dilated pupil on side of injury, ipsilateral
what is CN V and it’s function?
trigeminal; corneal reflex, chewing
what is CN VIII and it’s function?
vestibulocochlear; intactness of this nerve is tested by Doll’s eyes and cold caloric exam
what is CN IX and it’s function?
glossopharyngeal; swallow, gag
what is CN X and it’s function?
vagus; pharyngeal/laryngeal movement
the basal vertebral supplies what area of the brain?
lower areas, brain stem
the carotids supply what area of the brain?
upper areas; left internal carotid is dominant for most
what is the function of the frontal lobe?
personality, abstract thought, long-term memory
what is the function of the temporal lobe?
hearing, sense of taste/smell, interpretations
what is the function of the occipital lobe?
vision, visual recognition, reading comprehension
what is the function of the parietal lobe?
object recognition by size, weight, shape; body part awareness
what is the function of the cerebellum?
coordination, balance, gait
consciousness depends on what?
intact cerebral cortex and reticular activating system (RAS)
what is RAS?
network of neurons connecting the brain stem (lower RAS) to cortex (higher RAS)
upper RAS - awareness;
lower RAS - sleep-wake cycle; if damaged coma occurs
which area of the brain is responsible for speech/language?
Broca’s area in left hemisphere; expressive/receptive aphasia
what is the first sign of a Neuro problem?
change in LOC
decussation (crossing) of motor fibers occurs where?
medulla; motor problems are contralateral
flaccidity = medulla dysfunction
abnormal flexion or decorticate posturing is a dysfunction where?
hemispheric
distension or decerebrate posturing is a dysfunction where?
midbrain, pons
how can an adult have a positive Babinski reflex?
due to pressure on pyramidal/motor tracts in cerebrum, found on opposite side of damage
what is Doll’s eyes?
oculocephalic reflex assessment for CN 3, 6, 8
(+) is good; eyes move in opposite direction
“it’s good to be a doll”
what is the caloric ice test?
oculovestibular reflex
eyes held open while ice water injected slowly
(+) is good; eyes move toward ice water injection
what is Cushing’s triad?
sign of herniation of brain
- increasing SBP, WIDENING pulse pressure
- decreasing HR
- decreasing RR
- VS changes are a late sign of Neuro injury, brain stem involvement
what respiratory changes can be seen with a midbrain, pontine, and medulla problem?
hyperventilation; apneustic breathing; ataxic, ARREST
what is homonymous hemianopsia?
loss of vision in half the field of each eye
damage to OPTIC NERVE CN II
occurs opposite the side (contralateral) of problem
results in neglect of affected side
what are some general Neuro assessment principles?
eyes deviate toward pathology
pupil changes are ipsilateral, same side as pathology
visual changes are contralateral, opposite of pathology
motor changes are contralateral side of pathology
Babinski is contralateral, opposite side of pathology
if pathology on both sides, bilateral Babinski
when does brain death occur?
when swelling within the brain becomes so severe that structures of the brain are squeezed to the point where blood can’t get up into brain and death may occur
what is uncal herniation? where is the shift and how does it affect LOC?
displacement of temporal lobe (uncus) against the brain stem and 3rd CN (oculomotor, pupil)
lateral shift, NO initial change in LOC
what happens to the parasympathetic innervation in uncal herniation?
parasympathetic innervation is compressed to affected side = blown pupil on same side (ipsilateral) seen before change in LOC
what S/S do you see in uncal herniation?
babinski on opposite side
slight weakness, pronator gift to opposite side
stupor, coma, posturing, bilateral fixed and dilated pupils, death
what is uncal herniation most often caused by?
epidural hematoma that occurs in temporal area
what is central herniation? what are the changes in LOC?
swelling on both sides, downward displacement of hemispheres; usually due to diffuse edema, slower development; slight change in LOC and then coma
what happens to the parasympathetic innervation in central herniation?
first both pupils are small (1-3mm) then parasympathetic innervation on both sides is suppressed and both pupils dilate
what S/S do you see in central herniation?
babinski bilaterally; death
what is central herniation caused by?
cerebral edema secondary to encephalopathy or stroke
what is encephalopathy?
any diffuse disease of the brain that alters brain function/structure
hypoxic, metabolism, hepatitis, drugs, infection
what are some S/S of encephalopathy?
loss of memory and cognitive ability
personality changes, agitation
inability to concentrate, lethargy, progressive LOC, sz, coma, brain death
what are the two types of strokes?
- embolic, ischemic = TIA 24 hrs, infarct
- hemorrhagic = intracerebral, SAH, AVM