Neuro week 1 Flashcards
What does the central nervous system consist of?
Brain and spinal cord
What does the peripheral nervous system consist of?
cranial nerves and spinal nerves
Nervous system function
Control all motor, sensory, autonomic, cognitive and behavioral activities
What is the PNS further divided into?
somatic and autonomic
Synapse
gap between where the two neurons meet. Either the neuro is going to tell the next one to do something (excite) or stop (inhibit)
What does a neuron do?
Communicate messages/information from one neuron to the next or to the target cell. They either stimulate/terminate the activity of the target cell.
Catecholamine: when are they released?
in response to physical or emotional stress
What are examples of catecholamines?
Noradrenaline
Adrenaline (epinephrine)
Dopamine
What does adrenaline (epinephrine) do?
Hormone produced outside the brain, break down in communication, weakness and rapid fatigue of muscles under voluntary control.
Acetylcholine
major transmitter of the parasympathetic nervous system
Acetylcholine - source
Many areas of the brain; autonomic nervous system
Acetylcholine: action
Usually excitatory; parasympathetic effects sometimes inhibitory (stimulation of heart by vagal nerve) – voluntary muscle contraction, controls heartbeat, and stimulates hormones
Acetylcholine: example of dysfunction
↓ Leads to Myasthenia gravis
Serotonin: source
-Brainstem, hypothalamus, dorsal horn of the spinal cord
Serotonin: action
Inhibitory, helps control mood and sleep, inhibits pain pathways, regulation of appetite and temperature
Serotonin: example of dysfunction
↓ Leads to depression
Dopamine: source
Substantia nigra and basal ganglia
Dopamine: action
Usually inhibits, affects behavior (attention, emotions) and fine movement but can also be excitatory
- Plays a role in behavior, learning, sleep, mood, focus, attention, immune health, pleasurable reward
Dopamine: example of dysfunction
↓ Leads to Parkinson disease (found in the basal ganglia. Hard for them to initiate movement and to smooth movement out)
Norepinephrine: what?
(major transmitter of the sympathetic nervous system) * fight or flight
NE: source
Brainstem, hypothalamus, postganglionic neurons of the sympathetic nervous system
NE: action
Usually excitatory; affects mood and overall activity
Seen rarely
Gamma-aminobutyric acid (GABA): source
Spinal cord, cerebellum, basal ganglia, some cortical areas
GABA: action
Inhibitory
*Mood modulator – Low levels lead to restlessness, anxiety and irritability
GABA: example of dysfunction
↓ Leads to seizures
Enkephalin, endorphin: source
Nerve terminals in the spine, brainstem, thalamus and hypothalamus, pituitary gland
Enkephalin, endorphin: action
Excitatory; pleasurable sensation, inhibits pain transmission
Enkephalin, endorphin: example of dysfunction
Poor pain control
If we do not have enough endorphins lack of pain control
Cerebrum consists of what?
2 hemispheres Thalamus hypothalamus basal ganglia connections for cranial nerve II and II
What does brainstem consist of?
midbrain
pons
medulla oblongata
connections for cranial nerves III through XII
Thalamus
relays information regulation of conscious and alertness
Hypothalamus job
Important for endocrine system
Regulates the pituitary secretion of hormones influencing metabolism, reproduction, stress response, and urine production
It works with the pituitary to maintain fluid balance
Emotional, Responses, aggressive and sexual behavior
Hunger, sleep/wake cycle, BP
Controls and regulates the autonomic nervous system and maintains temperature regulation by promoting vasoconstriction or vasodilatation.
Basal ganglia function
Controls fine motor movments
Planning and coordinating movements and posture
Inhibit unwanted muscular movement
Disorders results in exaggerated uncontrolled movements
Muscle rigidity
Athetosis
Chorea
Parkinson disease
Huntington disease
Spasmodic torticollis
Athetosis
Movement of a slow, squirming, writhing, twisting
Chorea
spasmodic, purposeless, irregular, uncoordinated motions of the trunk and extremities and facial grimacing
Brainstem function
autonomic function (involuntary), HR, breathing, swallowing
Midbrain, pons function overall
Motor and sensory pathways
Pons (portion of it) controls what?
HR, respiration and BP
Medulla oblongata: function
respiratory function
Cerebellum function
Coordination and movement Balance (postural) Awareness of body parts. Balance Coordination Timing Damage results in loss of muscle tone, weakness, fatigue Ataxia and incoordination
Frontal lobe
Largest lobe
The major functions are concentration, abstractthought, information storage or memory, and motor function.
The frontal lobe is responsible in large part for a person’s affect, judgment, personality, emotions, attitudes, and inhibitions, and contributes to the formation of thought processes.
Motor strip location
Location: frontal lobe
lies in the frontal lobe, anterior to the central sulcus
What does the motor strip do?
responsible for muscle movement
What are nursing consideration when working with a client who has damage to temporal lobe?
receptive speech issues, effected long term memory…reinforce teaching, chart to help them ID letters/objects to help them communicate what they want/need, pictures to remind family members, patience with them, giving them time to determine if they have aphasia or are confused, yes/no questions
What are nursing considerations when working with a client who has damage to their frontal lobe?
safety, fall risk, siderails (only 3 max.), etc.
Parietal lobe function
primary sensory cortex
This lobe analyzes sensory information such as pressure, vibration, pain, and temperature, and relays the interpretation of this information to the thalamus from the sensory cortex.
It is also essential to a person’s awareness of the body in space, as well as orientation in space and spatial relations.
Where is the parietal lobe?
posterior to the motor strip
Stereogenesis
ability to perceive an object using the sense of touch
processed in parietal lobe
What are nursing considerations when working with a client who has damage to parietal lobe?
walkers/assistive devices, communicate location of belongings/food, assistance while getting up, good lighting, correct temperature, nonverbal cues, remove tripping hazards)
Temporal lobe function
contain the auditory receptive areas
The interpretive area of the temporal lobe provides integration of visual and auditory areas and plays the most dominant role of any area of the cortex in thinking
Long-term memory recall is also associated with this lobe.
Where are the auditory and receptive areas located in the temporal lobe?
around temple regions
What is located in the posterior region of the temporal lobe
is the area responsible for receptive speech referred to asBroca’s area and Wernicke’s area.For most people, whether right- or left-handed, Broca’s area and Wernicke’s area. is in the left lobe
Occipital lobe function
primary visual cortex
visual reflexes
involuntary eye movements.
Nursing considerations when working with a client who has occipital lobe damage?
placing belongings/food close and describing where it is/placing belongings in their center field of vision
What are the structures that protect the brain?
Bones
Membranes
Fluid cushioning
Chemical (?)
Skull
Hard, protecting it from injury
What are meninges?
connective tissue covering the brain and spinal cord
Provides protection, support and nourishment
What are the 3 meningeal layers?
dura, arachnoid and pia
Dura
outermost meningeal layer, very tough, thick, inelastic, fibrous and gray
Epidural layer
potential space that lies outside the dura (meninge)
Arachnoid layer
– middle membrane, thin, delicate membrane – white due to no blood supply.
Has small finger-like projections (villi) which absorb CSF
What happens when trauma occurs to the arachnoid layer?
When trauma occurs (trauma or hemorrhagic stroke) the villi become obstructed, and hydrocephalus can occur – also blocks the absorption of CSF leaving it to accumulate.
Pia (meningeal layer)
thin, transparent, hugs the brain – very vascular
Herniation
when the cranial cavity/brain tissue is being compressed or displaced downward.
Normal neurological assessment
Pain Headaches/Migraines Seizures Dizziness and Vertigo Visual Disturbances Weakness Abnormal Sensation
Family History
Social History
Neuro assessment: assessing cerebral function
LOC = primary energy for the brain is glucose. Brain is dependent on blood flow for brain glucose. When blood sugars drop
Mental status - short/long term memory
Perception
Motor ability
Language ability
agnosia
inability to interpret or recognize objects seen through the special senses
Neuro assessment: physical assessment
Cerebral function
Cranial nerves
Motor system
Neuro assessment: motor system
strength balance coordination ataxia Romberg test grading deep tendon reflexes sensory examination
Ataxia
incoordination of voluntary muscle action (usually walking or reaching for objects)
Romberg test
balance test – feet together, arms side, first with eyes open, then closed both for 20-30 seconds, slight swaying is normal, loss of balance is + test
Deep tendon reflexes: grading
absence of reflexes is significant 0-4+ ( can be subjective) present, diminished, absent
Deep tendon reflexes: clonus
hyperactive - sustained
Deep tendon reflexes: superficial reflexes
include corneal, gag/swallow, upper/lower abdominal, plantar reflexes
Corneal reflex
clean wisp of cotton lightly touching the outer corner of each eye on the sclera – if blink ok, can be unilateral or bilateral, need eye protection to prevent corneal damage
Gag reflex
gently touching the back of the pharynx with a cotton tipped applicated. Must touch both sides of the uvula – swallowing precautions if no gag reflex
Plantar (babinski) reflex
stroking the lateral side of the foot with a tongue blade – intact CNS = toes curl, not intact CNS = toes fan out
Broca area function
control of muscles for speech production and ability to comprehend grammatical structure
wernicke’s area
comprehension of speech sounds and language
Diagnostic evaluation: Computed tomography scanning nursing considerations
allergies (shellfish) Fluids if receiving constrast Preparation Lie quietly Kidney function
PET: preparation
sensations
dizziness
lightheadedness
HA
no surar prior; typically NPO (no dextrose fluids)
PET: contraindications
pregnancy and breastfeeding
MRI: nursing considerations
Relaxation techniques
Magnetic field - NO nic patch
Monitor kidney function
Cerebral angiography: nursing considerations
well hydrated - clear liquids
monitor injection site for hematoma
void prior to procedure
client will experience a brief feeling of warmth in face, behind eyes, jaw, teeth, tongue and lips with a metallic taste when contrast is injected
check pulses
monitor neuro s/s for at least 24 hours after
EEG: nursing considerations
sleep deprived, taking away seizure medications
Lumbar puncture: nursing considerations
Headache most common s/s after (May occur a few hours to several days after the procedures)
- Bedrest after
- Bifrontal or occipital (location HA)
- Severe upon standing
What is the lumbar puncture HA caused by?
CSF leakage at puncture site
lumbar puncture management
bed red, analgesic, hydration, blood patch
lumbar puncture complications
Herniation Abscess Epidural hematoma Meningitis Temporary voiding difficulties
Blood brain barrier
Endothelial cells in the brain capillaries
All substances entering the brain must filter through these cells and astrocytes
What can damage the BBB
Blood brain barrier can be altered by trauma, cerebral edema and cerebral hypoxemia
Implications for selection of medications to treat CNS disorders
Spinal cord
Connection between the brain and the periphery
Spinal cord - location
Extends from the foramen magnum at the base of the skull to the base of the first lumbar vertebrae
what is passed the 2nd lumbar?
cauda equina (nerve roots)
where is a lumbar puncture done?
L3-L4
Circle of Willis
Collateral circulation
Arterial bifurcations - common site for aneurysm formation
where all vasculature meets in brain (bottom part)
Describe the cerebral circulation
Brain does not store nutrients so it requires high blood flow
Blood flows against gravity
Describe the arteries in the brain
Arteries - internal carotids - anterior circulation
Vertebral arteries (become the basilar artery) - then into the vertebrobasilar artery - supplying the posterior circulation of the brain
Describe the veins of cerebral circulation
Veins - join larger veins - cross the subarachnoid space and empty into the dura sinuses (dura mater)
Empty into the internal jugular vein
What nerves are located in the cerebral hemisphere?
Olfactory (I)
Optic (II)
What nerves are located in the midbrain
Oculomotor (III)
Trochlear (IV)
What nerves are located in the pons?
Trigeminal (V)
Abducens (VI)
Facial (VII)
Acoustic (VIII)
What nerves are located in the Medulla?
Glossopharyngeal (IX)
Vagus (X)
Hypoglossal (XII)
Spinal accessory (XI)
Cranial nerve 1: name, type, dysfunction
Olfactory
Sensory
Dysfunction: inability to ID odor, termed anosmia
Cranial nerve 2: name, type, dysfunction
optic
sensory
Dysfunction: decreased visual acuity and visual fields
Cranial nerve 3: name, type, dysfunction
Oculomotor
Motor nerve
Dysfunction:
inability to move the eyes in the visual field described
Ptosis of affected eye
Nonreactive or dilated pupils
Cranial nerve 4: name, type, dysfunction
Trochlear
Motor
Dysfunction: inability to look down and in
Cranial nerve 5: name, type, dysfunction
Trigeminal
Mixed nerve type
Dysfunction:
- Absence of corneal reflex
- Diminished sensation to forehead, maxillary and mandibular region
- Weakness of muscles responsible for chewing
Cranial nerve 6: Name, type, dysfunction
Abducens
Motor
Dysfunction: inability to look laterally, double vision
Cranial nerve 7: name, type, dysfunction
Facial
mixed nerve type
Dysfunction:
- facial paralysis
- Facial asymmetry, droop of mouth
- Absent nasolabial fold
- Decreased ability to taste
Cranial nerve 8: name, type, dysfunction
Accoustic
sensory
dysfunction: decreased hearing in affected ear
Cranial nerve 9: name, type, dysfunction
Glossopharyngeal
Mixed
Dysfunction: Dysphagia, Absence of gag reflex
Cranial nerve 10: name, type, dysfunction
Vagus
mixed nerve type
Dysfunction: Hoarse or nasal quality to voice, Slurred speech
Cranial nerve 11: name, type, dysfunction
Spinal accessory
motor nerve
dysfunction: inability to shrug shoulders
Cranial nerve 12: name, type, dysfunction
Hypoglassal
Motor nerve
Dysfunction: tongue weakness
Skull fracture: nursing considerations
Be alert for CSF leakage
- Rhinorrhea (nose leak)
- Otorrhea (ear leaking)
- raccoon eyes
- Battle’s signs
What should the nurse keep in mind if there is a CSF leakage is suspected?
Do not insert anything into the orifice is it leaking from
What are we concerned about when someone has a skull fracture or CSF leak?
Meningeal tear leading to meningitis
What are telltale signs of of meningitis
High fever, stick neck, n/v, HA, sensitivity to light, seizure, sleepy
What does CSF look like?
Should be clear and colorless
How can CSF be tested?
Lumbar puncture
What is normal for CSF? (what should be in it)
Less than 5 WBC in CSF,
50-80 glucose (minimal amount)
15-60 protein
Should NOT have RBC
What kind of patients might present with a CSF leak?
trauma and surgery are two most common
Causes of increase ICP
Injury Increased CSF Bleeding Hematoma Hydrocephalus Encephalopathy Subarachnoid Hemorrhage
What does CPP stand for?
Cerebral perfusion pressure
How do we figure out CPP (cerebral perfusion pressure)
MAP - ICP
Increased ICP: cranial vault
10% intravascular blood
80% brain tissue
10% CSF
an increase in any of these causes increased intracranial pressure
Brain tissue has limited ability to expand, compensation occurs by increasing absorption or decrease production of CSF or decreasing cerebral blood volume
What should a nurse do with anyone with increased ICP?
increase HOB at least 30 degrees
Signs and symptoms of ICP
(MIND) Mental status change Irregular breathing Nerve changes Decerebrate/decorticate
(CRUSHED) Cushing triad Reflexes Unconscious Seizures Headache Emesis Deterioration
What are receiving sensory impulses
Thalamus integrates all sensory impulses except olfaction
Awareness of pain
Recognition of touch and temperature
Sense of movement and position
Ability to recognize size, shape and quality of objects
May be integrated at the spinal cord or relayed to the brain
What is sensory loss
transection of spinal cord yields complete anesthesia below level of injury
Motor and sensory functions include what
upper/lower motor neurons
coordination
receiving/sending sensory impulses
sensory loss
Comparison of Lesions of the Upper Moto Neurons and Lower Motor Neurons
UPPER MOTOR NEURON LESIONS:
- loss of voluntary control
- increased muscle tone
- muscle spasticity
- no muscle atrophy
- hyperactive and abnormal
LOWER MOTOR NEURON LESIONS:
- loss of voluntary control
- decreased muscle tone
- flaccid muscle paralysis
- muscle atrophy
- absent or decreased reflexes
Gero: structural changes
Brain weight decreases
Cerebral blood flow reduced
DTR decreased or absent
Stage IV sleep is reduced
Gero: motor alterations
Flexed posture
Shuffling gait
Rigidity of movement
Reaction time decreased
Gero: sensory alterations
Visual and hearing loss
Home environment modification
Gero: temp regulation and pain perception
Need a warmer environment
Pain reaction decreased
Gero: taste and small alterations
Decreased appetite
Decrease smell
Smoke, gas leaks, bad food
Gero: tactile and visual alterations
Longer to recover moving from dark to light area
Difficulty identifying objects by touch
Gero: mental status
Drug toxicity
Delirium
Vitamin B deficiency
Thyroid disease
What are names of 6 primary brain tumors
Gliomas Meningiomas Acoustic neuromas Pituitary adenomas angiomas cerebral metasteses
Primary brain tumors: risk factors
Exposure to ionizing radiation and cancer Cig cell phone use powerlines genetic risk factors
Primary brain tumors: clinical manifestations
Increased ICP – seizures, ,localized symptoms sensory loss, facial paralysis (HA, papilledema (edema of optic disk), visual changes, Personality changes, fatigue, vomiting, visual disturbances
Primary brain tumors: assessment
check LOC, Emegent AIRWAY then metabolic eval – labs, structural
Primary brain tumors: medical management
Surgical, Radiation, Pharm = chemo
Primary brain tumor: nursing management
Monitor for increased ICP, neuro checks, VS
Spinal cord tumors: metastatic Spinal Cord Tumors
– common cancer to spread – lung, breast and GI
Spinal cord tumors: spinal cord compression
Medical Emergency = paralysis
Iv steroids (Dexamethasone)
Spinal cord tumors: assessment
Sensory changes
Back pain
Sphincter dysfunction
Spinal cord tumors: medical management
MRI diagnostic
Spinal cord tumors: nursing management
Pre-op care
Post-op = changes in condition
Managing pain
Promote home and community based care
