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Nervous System
- Central Nervous System (CNS)
- –Brain
- –Spinal Cord
- §Peripheral Nervous System (PNS)
- –Cranial Nerves (12)
- –Spinal Nerves (31)
- §Autonomic Nervous System
- –Sympathetic Nervous System
- –Parasympathetic Nervous System
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Skull & CSF
- §Skull
- §Meninges (dura mater, arachnoid, & pia mater)
- Dura mater = outer fibrous double layer
- Arachnoid = middle elastic membrane covering brain
- Pia = inner layer with blood supply to brain
§Blood supply
- §Cerebrospinal fluid
- –Colorless, odorless fluid
- –Choroid plexus; arachnoid villi
- –Cushions, maintains intracranial pressure, nutrition, and
- removes metabolic wastes
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4 major divisions in brain
Cerebrum – higher intellect; 4 lobes; contralateral = opposite side controls body
Diencephalon – relay station & homeostasis
Brain Stem – midbrain, pons & medulla oblongata with spinal cord
Cerebellum – balance & coordination; ipsilateral = same side controls body
Cerebrum, diencephalon, cerebellum, and brainstem
Gray matter (brain cell bodies)/white matter (myelinated nerve fibers)
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CEREBRUM
- §Frontal lobe =motor cortex
- –Broca’s area, expressive aphasia
§Parietal lobe =sensory cortex
- §Temporal lobe =auditory cortex
- –Wernicke’s area, receptive aphasia
Occipital lobe =visual cortex
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DIENCEPHALON
§Thalamus-relay station
§Hypothalamus-homeostasis
§Epithalamus-sleepiness - sleep/wake center
- §Subthalamus-ANS
- –Sympathetic
- –Parasympathetic
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Brain Stem
- §Midbrain
- §Pons
- §Medulla oblongata
- –10 of 12 cranial nerves (“CN’s”)
- –Contralateral/cross over
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Cerebellum
§Coordinating movement, equilibrium, muscle tone, and proprioception
Each hemisphere controls movement for same (ipsilateral) side of body
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Spinal Cord
- Continuation of medulla oblongata to L1, L2
- §Nerve fibers (tracts)
- §Myelinated nerves (white matter)
- –Descending (motor tracts)
- –Ascending (sensory tracts)
- §Gray matter (nerve cell bodies)
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Peripheral Nervous System
- Cranial nerves (12 pairs)
- –motor fibers (III, IV, VI, XI, XII)
- –sensory fibers (I, II, VIII)
- –mixed/both (V, VII, IX, X)
- Some say marry money
- but my brother says bad
- business marry money
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Cranial Nerves (“On old Olympic’s towering top, a Fin and
German viewed some hops”)
- I - Olfactory (smell info from nasal cavity)
- II - Optic (sight from retina; visual acuity & fields)
- III - Oculomotor (extraocular eye movement, eyelids)
- IV - Trochlear ( downward & inward eye movement)
- V- Trigeminal (Sensory of cornea, eyelids, forehead
- Motor: jaw opening & chewing)
- VI - Abducens (Lateral eye movement)
- VII - Facial (facial expression, rounded vowel sounds, taste-anterior 2/3)
- VIII - Acoustic (hearing & equilibrium)
- IX - Glossopharyngeal (swallowing, phonation, gag & taste-posterior 1/3)
- X - Vagus (heart, lungs, digestion, larynx, pharynx)
- XI – Spinal Accessory -( turn head, shrug shoulders)
- XII - Hypoglossal (tongue for speech & swallow)
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Peripheral Nervous System
- Spinal Nerves
- –31 pairs—emerge from segments of spinal cord
- 8 cervical
- 12 thoracic
- 5 lumbar
- 5 sacral
- 1 coccygeal nerves
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Superficial & Deep Tendon Reflexes (Reflex Arc)
- Superficial Reflexes -
- –Abdominal (upper T7-9, lower T10-11)
- –Cremasteric (T12, L1-2)
- –Plantar / Babinski (L4-5, S1-2)
- Deep Tendon Reflexes -
- –Biceps (C5-6)
- –Brachioradialis (C5-6)
- –Triceps (C6-8)
- –Patellar (L2-4)
- - Achilles (S1-2)
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Neuro. Problem-Based History
(“OLDCARTS”)
- §Headache
- §Dizziness/Vertigo/ Syncope
- §Seizures
- §Loss of Consciousness
- §Memory Loss
- §Tremors
- Changes in Movement/ Mobility
- Changes in Sensation (numbness & tingling)
- Dysphagia (swallowing problems)
- Aphasia/Dysphasia (communication problems)
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Neuro Health History: Past Medical History
- §Injury to head/spinal cord? Describe. Changes since injury?
- §Surgery on brain, spinal cord, or nerves? When? Outcome?
- §Stroke? Describe. When? Changes resulting from stroke?
- §Seizure disorder? Describe kind and how often. What prevents seizures?
- §Meningitis or encephalitis?
- §Chronic diseases?
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Family History
- Family History
- §Stroke?
- §Seizures?
- §Hypertension
- §Tumors of brain or spinal cord?
- Alzheimer’s disease
- All these conditions have familial tendencies, and may affect vision. If there is a positive answer to any of these conditions, the client’s risk of developing them increases
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Lifestyle & Health Practices
- §Noticed changes in ability to move around/participate in
- usual activities (ADL)?
- §Use of tobacco.
- §Chemical or occupational exposure, such as lead, insecticides or pollutants?
- §Diet deficient in niacin, folic acid or B12?
- §Medications, taking as prescribed?
- §Alcohol use per week?
- §Use/ever used marijuana, cocaine, barbiturates, tranquilizers, or other mood-altering drugs?
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Health History: Risk Factors
- §“Brain attack”, Cerebrovascular Accident (CVA)
- - used interchangable - faster you get intervention the better off they will be
- –Age: older at greater risk
- –Gender: men at greater risk than women (women – more than half of deaths from brain attacks)
- –Family history: risk greater if parent, grandparent, or sibling had a CVA
- –Previous brain or heart attack
- –Race (Blacks > whites) higher incidence of hypertension
- –Smoking
- –High blood pressure (HT)
- –Diabetes mellitus (DM)
- –Coronary artery disease (CAD)
- –Transient ischemic attack (TIA)
- –Atrial fibrillation
- –High serum cholesterol
- –Obesity
- –Excessive alcohol intake
- –Cocaine use
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Neuro. Physical Exam:
- §Mental status / level of consciousness
- §Cranial nerve exam
- §Motor and cerebellar exam
- §Sensory exam
- §Reflexes (deep tendon & superficial)
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Assess Mental Status
- §General Observation of:
- –Posture & body movements - should be erect with relaxed body tense indicates anxiety while slumped &
- slow with depression & bizarre = schizophrenia
- –Dress, grooming & hygiene (appropriate) -for weather
- outlandish = manic
- soiled = depression
- –Facial expressions esp. eye contact - Parkinson
- & Alzheimer’s with mask-like expressionless face
- –Mood/affect - positive attitude
- –Concentration/focus
- –Orientation x 3
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Assessment of Cognition
- •Recent memory - what ate past 24 hrs. or weather today
- •Remote memory
- •Memory of learned information - 3 unrelated words then repeat after 5 min., 10 min. & 30 min.
- •Abstract reasoning - proverb like rolling stone gathers no moss or how are orange & apple similar?
- •Judgment - driving & police car behind with lights & siren on (what do you do?)
- •Visual perception/construction
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Assess Orientation x 3
- §Awareness - determine if oriented to:
- §Date/time—first orientation to disappear
- §Place—2nd orientation to disappear
- §Person—last orientation to disappear
- –Orientation returns in opposite order
- §Arousal- determine Glasgow Coma Scale
- –Assess for best response to eye opening, motor response, and verbal response
- -Pain—1 descriptor used in assessment of best eye/motor response
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Assess Unconscious Patient
- Glasgow Coma Scale ( 3 to 15)
- Glasgow score 15 = optimal
- < 10 = emergency
- < 7 = coma
- Best eye-opening response
- §Spontaneously [4]
- §To verbal command [3]
- §To pain [2]
- §No response [1]
- §Peripheral v. Central Pain
- Best verbal response
- §Oriented, converses [5]
- §Disoriented, converses [4]
- §Inappropriate words [3]
- §Incomprehensible sounds [2]
- §No response [1]
- Best motor response
- –Obeys command [6]
- – Localization of pain—moves to try and remove stimulus [5]
- –Attempt to withdraw from stimulus [4]
- –Abnormal flexion (decorticate) [3]
- –Abnormal extension (decerebrate) [2]
- –No response [1]
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Decorticate Posturing
- caused by lesion at or above the brain stem
- §Rigidly still
- §Arms flexed
- §Fists clenched
- §Legs extended
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Decerebrate Posturing
- caused by lesion below brain stem - intracranial catastrophie
- §Rigid body position
- §Arms stiff, extended & pronated inward but fingers are extended out
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Examination Cranial Nerves
- §Evaluate speech—articulation, voice quality,
- conversation/health history (CN II – XII)
- §Test nose—smell (CN I)
- §Test eyes—visual acuity (CN II), peripheral vision
- §Observe eyes for extraocular movement (CNs III, IV, VI) in 6 cardinal fields
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Examination Cranial Nerves
- §Observe eyes—pupillary size, shape, equality, constriction, accommodation
- –PERRLA (CN III)
- –Ptosis (droopy eyelid)
- §Evaluate face—movement/sensation (CNs V/VII)
- –Motion (clench teeth & palpate masseter muscle)
- –Light touch over scalp, paranasal sinus & jaw
- –Deep sensation (blunt vs. sharp paperclip)
- –Corneal reflex
- Raise eyebrows, smile, puff cheeks, purse lips, show teeth, & close eyes with resistance
- §Test ears—hearing/balance (CN VIII)
- –Whisper test, Weber/Rinne (tuning fork)
- §Test tongue—taste (CNs VII,IX)
- –Sweet, salty (VII); sour, bitter (IX)
- –Not done unless reported problem
- §Inspect oropharynx—gag reflex/soft palate movement (CNs IX, X)
- –“aahhhh” test
- Touch posterior pharynx with tongue blade for
- gag
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Examination Cranial Nerves
- §Inspect tongue—movement, symmetry, strength, absence of tumors (CN XII)
- –protrude tongue, move toward nose, chin, side
- to side
- –press tongue against gloved finger
§Test shoulder/neck muscles—strength/movement (CN XI) shrug shoulders; turn head to side against hands/resistance
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Examination: Cerebellar : Balance & Coordination
"Drunk test"
- §Observe walking/gait
- §Romberg test - stant with feet together
- §Upper extremities-
- –Alternate thigh taps
- –Finger to nose
- –Fingers to thumb
- §Lower extremities-
- –Heel- to-toe walk
- –Hop on one foot
- –Stand on one foot x 5 sec
- –Heel –to-shin- in bed - take opposite heel and slide down shin
- –Deep knee bends
- –Walk on toes then on heels
- –Slide heel from knee to shin
- §Evaluate Muscle Strength
- –Client flexes muscles then resists when examiner applies opposing force (push/pull)
- Fasciculation = localized uncontrollable twitch
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Examination - Sensory Function
- §Eyes closed examine up extremities & check
- dermatome map
- - Tuning fork/cotton swab/paper clip - sharp & dull
§Kinesthetic position - atoms in motion - eyes closed and move finger or toe up or down - pt itdentifies
- §Stereognosis
- - familiar object in hand - key or quarter
- §Graphesthesia
- - draw a litter
- §2-point Discrimination
- - tell if touching in two places or one
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Exam: Deep Tendon Reflexes
- Evaluate DTRs muscle contraction, 4+ scoring system:
- 0 = no response
- 1+ = sluggish/diminished
- 2+ = active or expected
- 3+ = slight hyperactive, more brisk than normal
- 4+ hyperactive with intermittent clonus
- Triceps (C6, 7 & 8) contraction of triceps muscle; extension of elbow
- Biceps (C5-6)—contraction of biceps muscle; flexion of elbow
- Brachioradialis (C5-6) —pronation of forearm; flexion
- of elbow
- Patellar (L2, 3 & 4) —contraction of quadriceps muscles; extension of lower leg
- Achilles (S1 & 2)—contraction of gastrocnemius muscle; plantar flexion of toes
- Plantar/ Babinski (L4 & 5 S1 & 2)—plantar flexion of
- toes yet superficial reflex
- Ankle clonus—if hyperactive reflexes—sharply dorsiflex foot, maintain no movement
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Superficial Reflexes
- §Upper & Lower Abdominals – stroke outward from umbilicus
- §Cremasteric – stroke upper inner male thigh & ipsilateral testicle rises
- §Plantar/Babinski’s – sole of foot upward; normally (-) flex toes; abnormal (+) if big toe dorsiflex & others fan
- outward
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Elderly Neuro Variations
- Effects of aging on nervous system :
- §Dilation of brain ventricles
- §Cortical atrophy esp. frontal/temporal lobes
- §Decreased brain weight
- §Decreased norepinephrine & serotonin causes depression while decreased dopamine leads to Parkinson’s disease
- §Eye lens thickens; smaller pupil—brighter light for vision
- §50% of those >75 years report hearing difficulties
- §Short-term memory declines with age, longterm memory usually maintained
- –Changes in motor function—stooped, forward-flexed posture, slow gait
- –Change in gait—related to age-associated conditions (osteoarthritis/osteoporosis)
- –Loss of muscle strength and slow reaction esp. plantar & abdominal reflexes
- Visual deficits, loss of muscle strength, and slowed reaction time contribute to increased risk
- of falls
- Presbyopia = problems with near
- vision (farsighted) as age
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Nursing Dx Neuro
- §Risk for injury RT decreased sensation
- §Risk for aspiration RT impaired gag reflex
- §Impaired verbal communication RT aphasia
- §Acute or chronic confusion RT head injury
- §Impaired memory RT dementia
- §Self-care deficit RT paralysis
- §Incontinence RT spinal cord injury
- §Unilateral neglect syndrome RT CVA
- §Disturbed thought process RT drugs or ETOH (Risk of suicide)
- §Anxiety/Fear
- Low self-esteem
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Deep tendon reflexes
- §Biceps (inner elbow palm up)
- §Brachioradialis (wrist palm down)
- §Triceps (hand arm down)
- §Patellar (below knee)
- §Achilles (behind ankle)
- §Check for Ankle clonus if 4+ (dorsiflex foot – no movement is normal v. oscillations = clonus)
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