Neuro Flashcards
The nervous system consists of
Central nervous system
Peripheral nervous system
Autonomic nervous system
The neuron is
the structural and functional unit of the nervous system. Neurons initiate and transmit impulses to other neurons.
The neuron’s function
Composed of an axon and one or more dendrites.
Axon transmits impulses away from the
cell body to dendrites of other neurons
or directly to the cell bodies of other
neurons.
Dendrites receive impulses and
conduct them toward the nerve cell
body.
Neuron’s have both a
sensory and motor components
synapse
is the junction between neurons where an impulse is transmitted.
axon
long branch, transmits impulses
dendrites
receive impulses from other neurons
synapse
bridge between the axon and dendrites
neurotransmitters
are chemical agents involved in transmission of the impulse across the synapse.
you need these in order for the impulses to go over the bridge.
Myelin Sheath
sheath is a wrapping of a fatty material that protects and insulates the nerve fibers and enhances the speed of impulse conduction.
Afferent Neuron
sensory neuron that transmits impulses from the peripheral receptors to the Central Nervous System (CNS).
Efferent Neuron
is a motor neuron that conducts impulses from the CNS to the muscles and glands.
Myelin Sheath
acts like a wire. has the copper on the inside and a rubber coating that protects it. When that plastic coating breakdown, the wire doesn’t work. Same things happen to a myelin sheath. Sometimes if its not a lot of damage, it can repair itself, but if there is too much damage, then it will bot be able to be repaired.
internuncial neurons
( interneurons) are connecting links between afferent and efferent neurons.
central nervous system is composed of
brain and spinal cord
the brain is composed of
cerebrum, corpus callosum, basal ganglia, Diencephalon, brainstem, cerebellum
how do neurons work
the afferent neuron reports to the brain that there is something wrong. The brain then reports to the efferent neuron to physically change the situation. i.e. if your hand is on a hot stove, the afferent neuron reports this to the brain and then the brain tells the efferent neuron to remove your hand.
internuncial neurons
the links between the afferent and efferent neurons
cerebrum
outermost area is the cortex
Has two hemispheres
Each hemisphere is divided into
four lobes ( frontal, Parietal,
Temporal and Occipital )corpus callosum
large fiber tract that
connects the two hemispheres
basal ganglia
islands of gray matter within
white matter of cerebrum that regulate and
integrate motor activity originating in the cerebal
cortex. Part of the extrapyramidal system.
diencephalon
the connecting part of
the brain between the cerebrum and
the brain stem. It contains the:
a. Thalamus
b. Hypothalamusbrainstem
contains midbrain, pons and
medulla oblongata
respiratory, vasomotor, and cardiac type functions
cerebellum
coordinates muscle tone
and movements and maintains
equilibrium
issues in cerebellum causes ataxia, unsteady gait, surroundings.
frontal lobe
motor function, intellectual function, personality, injury to this lobe changes a person’s personality . Broca’s area is located in the frontal lobe. This is the motorized speech area. Allows us to speak and say what we want to say, be able to communicate. If there is a lesion on the frontal lobe, it causes aphasia and issues with expression through speech.
parietal lobe
sensory stimulation, sensation, touch, pressure, takes info coming in and makes sense of it .
temporal lobe
sensory stimulation, hearing, auditory, receptive, it contains wernicke’s area. This is the sensory speech area. Helps us to understand what someone is saying to us and what is written. If someone has a lesion on wernicke’s area, it causes issues with reception of what we say to them. It’s like we are speaking gibberish.
Occipital Lobe
everything associated with vision. this is where basal ganglia is located. These regulate motor activity that originates in the cerebral cortex. Parkinson’s is caused from this area
spinal cord
Serves as a connecting link between the brain and the periphery
Extends from foramen magnum to the second lumbar vertebra.
Ascending tracts are sensory pathways
Descending tracts are motor pathways
cerebrospinal fluid
Surrounds brain and spinal cord
Offers protection by functioning as a shock absorber
Allows fluid shifts from the cranial cavity to the spinal cavity
Carries nutrients to and from the nerve cells
too much CSF causes ICP, hydrocephalus
certain things cause CSF leakage. Its very clear color. It is very high in glucose when tested.
what is distinct of CSF
The center is clear and the rest is like a yellow halo coming out around it. you can see this if you catch it on a gauze pad
vascular supply of the CNS
Two internal carotid arteries anteriorly
Two vertebral arteries leading to basilar artery posteriorly
These arteries communicate at the base of the brain through the Circle of Willis
Anterior, Middle and Posterior cerebral arteries are the main arteries for distributing blood to each hemisphere of the brain
Brainstem and Cerebellum are supplied by branches of the vertebral and basilar arteries
Venous blood drains into dural sinuses then into internal jugular veins
peripheral nervous system
Spinal Nerves- 31 pairs carry impulses to and from the spinal cord. Each nerve is attached to spinal cord by two roots:
two roots of the peripheral nervous system are
dorsal posterior root, and the ventral anterior root
Dorsal posterior root
contains afferent
sensory nerves
ventral anterior root
contains efferent motor nerve fibers
cranial nerves
12 pairs that carry impulses to and from
the brain. Have sensory, motor or
mixed functions.
The 12 cranial nerves
I Olfactory: Sensory-carries impulses for sense of smell
II Optic: Sensory-carries impulses for vision
III Oculomotor: Motor-muscles for pupillary constriction, elevation of upper eyelid; 4 out of 6 extraocular movements
IV Trochlear: Motor-muscles for downward, inward movement of the eye
V Trigeminal: Mixed-impulses from face, surface of eyes (corneal reflex); muscles controlling mastication
VI Abducens: Motor- muscles for lateral deviation of eye
VII Facial: Mixed- impulses for taste from anterior tongue; muscles for facial movement
VIII Acoustic: Sensory-impulses for hearing (cochlear division) and balance (vestibular division)
IX Glossopharyngeal: Mixed-impulse for sensation to posterior tongue and pharynx ; muscles for movement of soft pharynx (elevation) and swallowing
X Vagus: Mixed- impulses for sensation to lower pharynx and larynx; muscles for movement of soft palate, pharynx, and larynx
XI Spinal accessory: Motor-movement of sternomastoid muscles and upper trapezius muscles
XII Hypoglossal: Motor-movement of tongue
autonomic nervous system
Part of peripheral nervous system
Includes those peripheral nerves (both cranial and spinal) that regulate functions occurring automatically in the body
Regulates smooth muscle, cardiac muscle, and glands.
Components: Sympathetic and Parasympathetic
neurological exam
Mental Status Exam (Cerebral Function)
Appearance and behavior
Level of Consciousness
Intellectual Function
Emotional Status
Thought Content
Language and Speech
Cranial Nerves
Cerebellar Function
Motor Functions
Sensory Functions
Reflexesfive point level of consciousness scale
1 Alert: Normal mental activity, aware,
mentally functional
2 Obtunded/Drowsy: Sleepy, very short
attention span, can respond
appropriately if aroused
3 Stupor: Apathetic, slow moving, blank
expression, staring, aroused only by
vigorous stimuli
4 Light coma: Not oriented to time, place or
person. Aroused only by painful stimuli-
response is only a grunt or grimace or withdrawal
from pain
5 Deep Coma: No response except decerebrate or decorticate
posture
decerebrate posturing
Decerebrate posture is an abnormal body posture that involves the arms and legs being held straight out, the toes being pointed downward, and the head and neck being arched backwards. The muscles are tightened and held rigidly. This type of posturing usually means there has been severe damage to the brain.
decorticate posturing
Decorticate posture is an abnormal posturing in which a person is stiff with bent arms, clenched fists, and legs held out straight. The arms are bent in toward the body and the wrists and fingers are bent and held on the chest.
This type of posturing is a sign of severe damage in the brain. People who have this condition should get medical attention right away.
pupil reaction and eye movement
Observe size, shape and equality of pupils (note size in millimeters)
Test reaction to light—pupillary constriction
Corneal Reflex
Oculocephalic Reflex
motor function
Test movement of extremities
Test muscle strength
MOTOR SCALE
5/5 moves against gravity and resistance
4/5 moves against moderate resistance
3/5 moves against gravity only
2/5 moves but not against gravity
1/5 muscle contracts-no movement
0/5 no visible or palpable movementparasympathetic nervous system
acetocholine
sympathetic nervous system
norepinephrine
abnormal respiratory movements
Cheyne-Stokes Central Neurogenic Hyperventilation Apneustic Breathing Cluster Breathing Ataxic Breathing Gasping Breathing Depressed Breathing
first assessment in neuro
patient answering questions appropriately, or are they way off
Second assessment in neuro
does there body language and facial expressions congruent with what they are saying
third assessment neuro
hows there speech clear slurred, normal rate and rhythm
fourth assessment neuro
do they answer you completely
fifth assessment neuro
how is there appearance, are they neat and dressed appropriately for the weather, for their age
sixth assessment neuro
how do they interact, are they angry, hostile, euphoric, do they answer you and treat you appropriately
neuro health history, presenting problem
Behavior changes, memory loss, mood
changes, nervousness or anxiety,
Headache, seizures, syncope, vertigo,
Loss of consciousness, speech problems
Vision, smell or motor problems, sensory
problems
diagnostic procedures for neuro
Xrays
Computed Tomographic Scan (CT scan)
Positron Emission Tomographic Scan
(Pet scan)
Magnetic Resonance Imaging (MRI)
Carotid Doppler Studies
Cerebral Angiography
Myelogram
Lumbar PunctureIncreased Intracranial Pressure Pathophysiology
Increase in brain tissue, vascular tissue, and cerebral spinal fluid volume can cause
an increase in pressure within the cranial cavity
Increase ICP can be caused by tumors, abscesses, hemorrage, edema, hydrocephalus, inflammation
Untreated can lead to displacement of brain tissue (herniation)
sixth assessment of neuro
is the patient hallucinating, or seeing things
Compensatory Mechanisms with Increased ICP
Cerebral blood flow decreases causing inadequate tissue perfusion.
Leads to increased PCO2 and decreased PO2
Triggers vasodilation and more cerebral edema
Can lead to herniation and death
assessment findings of ICP
Change in level of consciousness
Changes in vital signs
- widening pulse pressure
- pulse bounding and slows
- abnormal respiratory patterns
- Elevated temperature
Pupillary changes
Motor/Sensory abnormalities
Headache, projectile vomiting, hiccuping, papilledemamedical management of ICP
Goals: Treat cause, control seizures and other complications Maintain fluid and electrolyte balance Surgical intervention if needed Corticosteroids Osmotic diuretics, systemic diuretics Fluid restriction Barbituates, analgesics Airway management
nursing care for ICP
Maintain patent airway and adequate ventilation Monitor vital signs and neuro checks Maintain fluid balance Proper positioning Prevent further increases in ICP Monitor I&O carefully Prevent complications of immobility Give medications as ordered Assist with ICP monitoring Care of patient with hyperthermia
if your unable to solve a neurological assessment question its called
discalcula
expressive aphasia or nonfluent aphasia
inability to speak and write (broca’s)
receptive aphasia or fluent aphasia
cannot understand what you are saying to them. Like you’re speaking gibberish to them (wernicke’s)
global aphasia
they have both receptive and expressive aphasia (fluent and confluent) effects both broca’s & wernicke’s areas
What causes ICP
anything that takes up home in the skull and takes up space essentially is ICP
I.E. :
fluid that comes into the brain tissues/cells
blood
tumor
blockage of fluid
what fluid do you NOT use with a brain injury
dextrose 5% in water
NEVER EVER use this. Causes ICP
ICP left untreated
causes herniation of the brain. Brain goes down into the brain stem and patient dies
another problem with ICP
the body tries to compensate but compensatory mechanism doesn’t help .
when you have ICP what happens
impairs circulation to the brain. your not going to have adequate perfusion of oxygen . This causes increased PCO2 levels in the blood. this triggers a reaction in the brain. The brain responds by causing vasodilatation. This causes even more cerebral edema. The compensatory mechanism can complicate things.
why do we do ABG’s on brain injury patients
we are looking to see if they an elevated PCO2 and low PO2. this will trigger the compensatory mechanism. Which we DONT WANT
First signs and symptoms of ICP
First thing you notice, change in LOC of your patient. There is some change (become nervous, agitated, hyper, apathetic, problems concentrating, stupor)
Classic signs and symptoms of ICP
widening pulse pressure (systolic elevates, diastolic stays the same. no wider than 40mmg) Bradycardia (but a bounding pulse) elevated temp (late symptom) sometimes low temp (paradoxical effect) changes in Respirations
associated symptoms of ICP
headaches
projectile vomiting
hiccups
optic nerve can be swollen
how do you treat ICP
treat the cause of the ICP.
also treat seizures
fluids and electrolytes
maintain fluid and electrolytes, but you need to monitor closely to prevent too much fluid and increasing their ICP.
could be on a fluid restriction
corticosteroids
often used for ICP
dexamethasone (decadron) decreases inflammatory response at brain, and decreases ICP
osmotic diurectics
mannitol
works at cellular level to draw fluid out of the brain.
given IV. (must have a Foley in, if they are on mannitol)
systemic diurectic
lasix
bumex
must be loop given IV
barbituates
they put them on these to to lower their metabolic rate, an increased metabolic rate increases their ICP
analgesics
used for pain, but we don’t want to decrease their respirations
monitor ABG’s in ICP for
we don’t want CO2 to increase
we don’t want O2 to decrease
suctioning with ICP
suctioning pulls oxygen out.
pre-oxygenate them before suctioning and then oxygenate them again after you suction.
hold your breath when you do it
don’t put suction on when you’re going in, only on out
use sterile gloves and sterile catheter
how often do you do I & O’s with ICP
hourly
positioning ICP
semi- fowlers
not so high that the head tilts forward, you want the neck in neutral type position
which way do you want to turn someone with ICP
left. You do not want to turn right. Bad draining with Right side in brain.
you do not want hip flexion.
you want LOG rolling. good free flowing motion
epidural sensor
placed in epidural space.
indirect measurement of ICP
normal ICP rating
0-10
anything sustained above 15 is NOT good
intracranial pressure monitoring
catheter directly into ventricles in the brain. Measures the pressure directly in the brain. very invasive
someone with an Intracranial pressure monitor
check tubing for bubbles and kinks
change dressings
make sure any procedure that you do is sterile
how to treat hyperthermia with ICP
tepid soaks if everything else fails then use a hyperthermia blanket make sure they have a rectal probe in constantly check skin for frostbite they will start shivering, so you need to put them on medication ( i.e. thorazine) to prevent shivering
romberg test
stand with feet together with eyes open
then you have them close there eyes.
if they have a cerebellar problem they start to drift. can’t maintain their position sense.
if there is a cerebellar dysfunction
ataxia - hard time coordinating walk. (can’t go toe to heel)
they adapt and use a wide stance because their center of balance is better
what is different about a parkinson’s gait
no arm swing and they lean their head down and forward causing their back to hunch. huge safety issue
motor function neuro
muscle size
tone
strength
any abnormal movements
hyperkinesia
abnormal movements
tremors
rhythmic (to and fro) movement
Corea
uncooderinated movements
deep pain stimuli
never use on a patient who is with it
levels of reflexes
0- no reflex at all 1-hyporeflexia 2- normal 3- slightly hyperactive 4- hyperactive
what is the ideal on the glascow coma scale
15
what can make pupils look funny
cataract surgery can throw off a neuro assessment
occular cephalic reflex
see if there is normal eye movement
they stand behind the individual
they will hold open there eyelids
they move there head to one side
if the eyes are normal, they will go to the opposite side
if they stay on the same side its abnormal
dolls reflex/ conjugal movement
the normal movement of the eyes
cheyne stokes
periods of hyperventilation, regular and rhythmic
periods of apnea
cerebral dysfunction and metabolic disorders cause this
central neurogenic hyperventilation
rapid sustained respirations (higher 20s)
but blood levels are normal
usually brain stem dysfunction
apneustic breathing
prolonged inspiratory phase
hold it for a few seconds
then they will exhale
caused by a problem in the pons
what to look for with Cheyne stokes breathing
how long is the apnea lasting for.
watch for a whole minute
cluster breathing
a lot like cheyne-stokes
when they are breathing its regular breathing, then periods of apnea
caused by upper medulla or pons
ataxic breathing
irregular breathing
damage to the medulla
medications can cause it
gasping breathing
also called kaussmal’s
gasping breathing
usually seen in dying patients
depressed breathing
too much medication lower respirations (8-10)
neurological questions you can ask significant others
has there been behavior changes memory loss mood changes headaches seizures syncope vertigo loss of consciousness speech problems are they still able to do the ADL's
