Seminar on nervous system

Nervous system- its anatomy and physiology, and detailed neurological examination

2. SEMINAR ON NERVOUS
SYSTEM
Ms Alisha Talwar

3. ANATOMY AND
PHYSIOLOGY OF NERVOUS
SYSTEM

4. NERVOUS SYSTEM
Nervous system consists of the brain, spinal cord, sensory organs and Nerves
These organs are responsible for the control of the body and communication among its parts.
The brain and spinal cord form the control centre known as the central nervous system (CNS), where
information is evaluated and decisions made.
The sensory nerves and sense organs of the peripheral nervous system (PNS) monitor conditions inside
and outside of the body and send this information to the CNS. Efferent nerves in the PNS carry signals
from the control centerto the muscles, glands, and organs to regulate their functions.

5. FUNCTIONS OF NERVOUS SYSTEM
Sensory input–gathering information
To monitor changes occurring inside and outside the body
Integration-To process and interpret sensory input and decide if action is needed
Motor output
A response to stimuli
Activates muscles or glands

6. Classification of Nervous System

7. CENTRAL NERVOUS SYSTEM

8. REGIONS OF THE BRAIN
Cerebral Hemisphere
Diencephalon
Cerebellum
Brain Stem

9. •Paired (left and right)
superior parts of the
brain
•Include more than
half of the brain mass
•The surface is made
of ridges (gyri) and
grooves (sulci)
CEREBRAL HEMISPHERE

10. The cerebral hemisphere involved in logical resoning, moral
conduct, emotional responses, sensory intepretationand the
initiation of voluntary muscle activity.
“Pathways of nerve impulses are crossed pathways-means that
Left side of brain controls RIGHT SIDE OF BODYand Right side of
braincontrolsLEFT SIDE OF BODY”

11. Figure 7.13c
SPECIALISED AREA OF BRAIN

13. YELLOWBLUEORANGEBLACKRED GREENPURPLEYELLOW
REDORANGE GREENBLACKMAGENTACYANBROWN PINK
Left-Right Conflict
Your right brain tries to say the colour but your left brain insists
on reading the word.
LOOK AT THE CHART AND SAY THE COLOURNOT THE WORD

14. Sits on top of the brain stem
Enclosed by the
cerebral hemispheres
Three parts:
Thalamus
Hypothalamus
Epithalamus
DIENCEPHALON

15. Attaches to the spinal cord
Parts of the brain stem:
•Midbrain
•Pons
•Medulla oblongata
BRAIN STEM

16. •Two hemispheres with
convoluted surfaces
•Provides involuntary
coordination of body
movements
•“Arbor vitae” design of
white & grey matter
CEREBELLUM

17. FUNCTIONS OF LOBES

18. Extends from the
medulla oblongata to
the region of T12
Below T12 is the cauda
equina(a collection of
spinal nerves)
Carries sensory and
motor information
SPINAL CORD

19. PERIPHERAL NERVOUS SYSTEM

20. Sensory (afferent) division -Nerve fibers that carry information to
the central nervous system
Motor (efferent) division -Nerve fibers that carry impulses away
fromthe central nervous system.
Somatic system:
voluntary
Autonomic system:
involuntary
PERIPHERAL NERVOUS SYSTEM

21. AUTONOMIC NERVOUS SYSTEM

22. The involuntary branch of the nervous system
Consists of only motor nerves
Divided into two divisions
Sympatheticdivision(stimulates) –“fight or flight” response. Its activation
results in increased heart rate and blood pressure.
Parasympatheticdivision(inhibits) –“housekeeping system” It maintains
homeostasis by seeing that normal digestion and elimination occur and
that energy is conserved.
AUTONOMIC NERVOUS SYSTEM

23. NEURON

24. •Dendrites–conduct impulses toward
the cell body
•Cell body (soma): contains organelles
& Nisslsubstance (specialized rough
ER)
•Axons–conduct impulses away from the
cell body
•Schwann cells –produce myelin
sheaths in jelly-roll like fashion
•Nodes of Ranvier –gaps in myelin
sheath along the axon
NEURON

25. CLASSIFICATION OF NEURON
On the Basis of Function
•Sensory(afferent) neurons-Carry impulses from the sensory receptors
•Interneurons(association): “connector”
•Motor(efferent) neurons-Carry impulses from the central nervous system

27. CLASSIFICATION OF NEURON
On the Basis of Structure

29. Reflex–rapid, predictable, and involuntary responses
to stimuli
Reflex arc –direct route from a sensory neuron, to
an interneuron, to an effector
REFLEX ARC

30. 12 pairs of nerves
that mostly serve the
head and neck
Numbered in order,
front to back
Most are mixed
nerves, but three
are sensory only
CRANIAL NERVES

32. FACTS ABOUT NERVOUS SYSTEM
There are more nerve cells in the human brain than there are stars in the Milky Way
If we lined up all the neurons in our body it would be around 965 km long
There are 100 billion neurons in your brain alone
A newbornbaby's brain grows almost 3 times during the course of its first year
The left side of human brain controls the right side of the body and the right side of the brain
controls the left side of the body
A new born babyloses about half of their nerve cells before they are born

33. There are about 13, 500,00 neurons in the human spinal cord
The nervous system can transmit nerve impulses as fast as 100 meters per second, and in some cases,
the speed of transmission is around 180 miles per hour
A man's brain has 6.5 times more graymatter compared to women, but a woman's brain has 10 times
more white matter compared to men
Your nervous system cannot function properly in the absence of potassium and sodium ions.Vitamin B is
equally essential for your nervous system.

38. NEUROLOGICAL
EXAMINATION

39. NURSINGHISTORY
•Current HealthHistory
–Headaches, memory and concentration, visual disturbances, hearing,
balance, dizzy spells, speech, muscle strength, abnormalsensations
•Past HealthHistory
–Head injury, spinal cord injury, surgery,seizures
•FamilyHistory
–Neurological diseases, headaches, HTN, stroke,DM
•Social History andHabits
–Diet, vitamin deficiencies, ability to read or concentrate,
exposure to toxins or chemicals, alcohol or drug use, sexual
difficulties, sleep problems
•Medication History-neuro as well as allothers

40. WHAT ARE THE COMPONENTS AND HOW DO I DOCUMENT
THEM?
Neuro:
Mental Status
Language, Speech
Cranial Nerves
Motor
Reflexes
Sensory
Cerebellar
Gait

41. COMPLETENEUROLOGICALASSESSMENT HAS 5 COMPONENTS
•CerebralFunction
•Cranial Nerve Function:I-XII
•Cerebellar and MotorFunction
•SensorySystem
•Reflexes

42. NEUROCHECK
•Level of consciousness(LOC)
•Pupil response andsize
•Verbalresponsiveness
•Extremity strength and movement
•Vitalsigns
Establishing BASELINE and regularly re-evaluating key indictors
reveals trendsand detects changes warning signs of problems

43. CEREBRALFUNCTION
•Level ofconsciousness:
–Level of arousal: SubcorticalRAS
•Alert lethargic unresponsive
•Auditorytactilepainful stimuli to elicit response
–Level of orientation: Cortexactivity
•Person, place,time
•Speech
–Quality:Clear,slurred
–Verbal responses appropriate ornonsensical
–Ability to understand and followcommands
–Awareness of and difficulties withcommunication

44. 44
ASSESSING LOC:
GLASGOW COMA SCALE
Eye opening
Verbal responsiveness
Motor responsiveness

45. 45
PHYSICAL EXAMINATION
Levels of Consciousness
Alert-awake or easily aroused
Lethargic-not fully alert, drifts off when not
stimulated
Obtunded-sleeps most times, difficult to arouse (loud
noise, vigorous shaking or pain)
Stupor-need persistent loud noise or pain for
arousal; responds to stimuli
Coma-no response
(Jarvis CH 2)

47. PUPIL REACTION SCALE
•Assess Pupillary Status and Eye movement
Size of pupils should be equal
Reaction of pupils
Accommodation: pupillary constriction to accommodate near vision
Direct light reflex: constriction of pupil when light is shone directly into the
eye
Consensual reflex: constriction of the pupil in the opposite eye when the
direct light reflex is tested.
•Evaluate ability to move eye
Note nystagmus
Ability of eyes to move together
Resting position of iris should be at mid-position of the eye socket
•PERRLA

49. CEREBRALFUNCTION:
Verbal Responsiveness andSpeech
•Dysarthria: difficulty with mechanics of speech
•Aphasia:
–TEMPORAL-receptive
•Inabilitytounderstandor processspeechWernicke’s
•Auditory: spokenword
•Visual: writtenword
–FRONTAL-expressive
•Inability to form or use languageBroca’sArea
•Spoken OR written orBOTH

50. MINI-MENTALSTATE
•Widely usedtool
•Assesses only cognitiveabilities
–LOC, abstract reasoning, arithmetic calculations, writing
ability, memory and judgment
•Objective score based onresults

52. CRANIAL NERVES(CNS)
•CN I-Olfactory
•CN II-Ophthalmic
•CN III-
Occulomotor*
•CN IV-Trochlear*
•CN V-Trigeminal
•CN VI-Abducens*
•CN VII-Facial
•CN VIII-
Vestibulocochlear
•CN IX-
Glossopharyngeal
•CN X-Vagus
•CN XI-Spinal
Accessory
•CN XII-Hypoglossal

53. CRANIAL NERVEI
•Olfactory nerve(sensory)
–Vulnerable to damage in frontal head, basilar, and
facialinjuries
–Performed one nostril at atime
–Able to correctly identifysmells

55. CRANIAL NERVEII
•Optic nerve(sensory)
–Visualacuity,visualfields,ophthalmicexamofretinal
structures
–Area and extent of visual field loss depends on
location ofproblem
Use the snellenchart to check/test:
-distant vision
-color
Client should be 20 feet distant from the chart
Use an object to occlude one eye
Evaluate the vision one eye at a time

56. VISUAL FIELDDEFECTS

57. CRANIAL NERVEIII
•Oculomotor nerve(motor)
–Elevation ofeyelid
–Muscles of eye (with IV andVI)
–Assess pupil size, shape, response to light and accommodation
parasympatheticinervation
–Assessesmidbrain
–Normal response: PERRLA-> pupils equal round reactive to light and
accommodation
•How do you test foraccommodation?
•If PERRL, usually no need totest

58. CN III, CN IV, CNVI
•Oculomotor, trochlear, abducens nerves (motor)
–Assess EOM’s
–Assesses midbrain andpons

60. CN V: TRIGEMINAL NERVE (SENSORY
ANDMOTOR)
•Sensory: threebranches:
–Opthalmic, Maxillary,Mandibular
•Motor:
–Muscles ofmastication
•Palpate temporal and massetermuscles
•Open mouthsymmetry
–Cornealreflex
•? Contactwearers

62. CN VII: FACIAL NERVE (SENSORY ANDMOTOR)
•Sensory: taste toanterior 2/3
oftongue
•Motor: Facialexpression and
secretion ofsaliva
–Wrinkle forehead, raise and
lower eyebrows,smile and show
teeth, puff cheeks, closeeyes
–Observe forsymmetry
•UMN problems vs.facial

64. CN VIII: ACOUSTIC NERVE(SENSORY)
•Vestibulocochlearnerve:
–Hearing (cochlear) and balance(vestibular)
•Testing: Tuning Fork: Weber and Rinnetests
–Weber: tuning fork to center of forehead:
•NORMAL: hear equally in bothears
–RINNE: tuning fork to mastoid process then
auditory canal
•NORMAL: hear air conduction 2X as long as
bone (Rinnepositive)

66. CN IX AND CNX
•Glossopharyngealand Vagus
•Sensory andmotor
•Assesstogether
–Taste posterior 1/3of tongue
–Swallowing, gagreflex
–Movement ofpharynx
(ahhhhh)
•Assessesmedulla

68. CN XI: SPINAL ACCESSORYNERVE
•Motor
•Shrug shoulderstrapezius
•Turn headsternocleidomastoid

70. CN XII: HYPOGLOSSALNERVE
•Motor
•Tongue movements,strength
•Speech sounds: d, l, n,t

72. MOTORASSESSMENT
•Assess muscle strength, tone,size
–Observe for decreased fine motormovements
–Finger grasp, armstrength
–Compare side toside
•Can indicate UMNproblems:
–Degenerative cerebral disease, trauma or ischemia
•Can indicate LMNdisease:
–Problems within spinal cord: cord compression or injury

74. CEREBELLARFUNCTION
•Balance:
–Tandem, heel-toewalking
–Romberg test (feet together, eyesclosed)
•Coordination:
–Rapid alternatingmovements
–Finger to nose to fingertest
–Heel down shin

75. CEREBELLARFUNCTION: ABNORMALFINDINGS
•Ataxia: incoordination of voluntary muscle action
•Dysdiadochokinesia: inability to do rapid alternatingmovement
•Dysmetria: pastpointing
•Positive Romberg’ssign
–Pt sways badly or loses balancepositive Rombergsign
•If cerebellar, pt sways with eyes open or closed
•If proprioceptive ( posterior columns) patient OK with eyes
open

76. GAITDISTURBANCES
A.SpasticHemiparesis
B.SpasticParesis (Scissors
Gait)
D.FootDrop
E.SensoryAtaxia
(+ Romberg’seyes closed)
G.CerebellarAtaxia
(+ Romberg’seyes open or
closed)
F.Parkinsonian

77. DEEP TENDON REFLEXES ASSESSING SPINAL
CORDLEVEL
•Biceps
C5C6
•Brachioradialis C5C6
•Triceps
C7C8
•Abdominal
T8T9T10
•Patellar (knee-jerk) L2L3L4
•Achilles

78. GRADINGREFLEXES
•Grade0-4+
–0 reflexabsent
–2+ “normal”
–4+ CLONUS UMN
disease
•Compare side toside
•Manyvariations
•Patient must berelaxed

79. SUPERFICIALREFLEXES
•Graded as PRESENT orABSENT
•Corneal Reflex (CNV)
–Present Briskblink
–Loss in stroke, coma, CONTACTWEARERS
–EYE PROTECTION
•Gag Reflex (CNX)
–Present Elevation of uvulabilaterally
–Loss instroke
–ASPIRATIONPRECAUTIONS

80. PLANTAR REFLEX: BABINSKIRESPONSE
•Stroke lateral aspect of sole offoot
•NORMAL response plantarFLEXION
•BABINSKI response pathological inadult
–POSITIVE BABINSKI: Dorsiflexion of great toe with fanning of other
toes
–Indicates upper motor neurondisease

81. GRASP REFLEX:SIGNIFICANCE
•COMA: Stimulation of palm ofhand
–POSITIVE: Pt will graspfirmly
–Will not let go tocommand
–Indicates frontal lobe damage, thalamic
degeneration, cerebralatrophy

82. SENSORYFUNCTION
•Assessing dorsal columns or parietallobe
–Light touch, position sense,vibration
–Stereognosis: able to identify object placed in hand
–Graphesthesia
–Extinction: touch one or both sides ofbody
–Two point discrimination
•Spinothalamic tracts and parietallobe
–Pain andtemperature
•Sharp ordull

83. NEUROLOGICAL DIAGNOSTICS

84. ANATOMICALPLANES

85. SKULL AND SPINALX-RAYS
•C-spine films routinely ordered in
multiple trauma to rule out cervical
fracture
•X-rays used to evaluate skull, spinal
abnormalities, pituitarytumor
•Frequently ordered to evaluate low back
pain

86. COMPUTERIZEDTOMOGRAPHY
•Cross sectional images brain and spine
using radiation andcomputer
•More specificviewsofboneand
tissue thanX-rays
•Useful in detecting tumors,
hemorrhages, hematomas, ventricular
enlargement
•May be used with IVcontrast

87. CT: PATIENTPREPARATION
•Pt must be as motionless aspossible
–Confused combative client/ pediatric considerations
•If contrastused:
–?? allergies to shellfish
–NPO for 4 hours prior totest
–IV started in radiology (if not already inplace)
•Should remove wigs, hairpins, clips and jewelryinterfere with image
seen
•Test should take 30-60minutes
•Post-test: resume diet and encourage fluids ifIV

88. PETSCAN
•Images of actual organ
functioning
•Inhaled or injected
radioactivesubstance
•Showsmetabolic
changes
–Alzheimer’s
–Braintumors
–O2 uptake afterstroke

89. MRI: NURSINGCONSIDERATIONS
•Use of electromagnet and radiowaves
•Check patienthistory!!
–PATIENTS WHO CANNOT HAVE MRI:
•Pacemakers
•Metal implants, plates, screws, or clips (old aneurysm surgeries!)
•IUD’s, metal heartvalves
•SAFETY:
–IV pumps, portable oxygen tanks cannot be in scanarea
•Patient Preparations andteaching:
–No metals: jewelry, credit cards,eyemakeup
–Process takes 45 minutes to1hourpt. must liestill
–MRI machine makes loud beatingnoise
–Closed MRI: tight space: problems withclaustophobia?
•May need Valium pre-test/ some cannottolerate

90. CEREBRALANGIOGRAPHY
•Injection of contrast medium into
cerebralcirculation
•Useful in detecting cause of stroke,
headaches,seizures
•Femoral access most commonly used
vessel
•Risk:stroke

91. CEREBRALANGIOGRAPHY:
Procedure & PatientPreparation
•Injection of contrast medium into cerebralcirculation
–Useful in detecting cause of stroke, headaches,seizures
•NPO solids 6-10hours
–Clear liquids/waterencouraged24 hoursprior
•Assess PT/ PTT
–Stop anticoagulants prior to test(usually)
•Contrast dye precautions/ informedconsent
•Patient AWAKE; slightsedation
•Femoral puncture mark peripheralpulses
•Burning or flushing with contrast injectionexpected
•Procedure will take 1-2hours

92. MR ANGIOGRAPHY(MRA)
•Utilization of MR technology to view
vasculature
•Same restrictions asMRI
•May use contrast material (gadolinium)
but is not iodinebased

93. MYELOGRAM
•Injection of contrast medium into subarachnoid
spacex-ray visualization
•Useful for visualizing obstructions within spinal
canal
–Dye bathes nerve rootsany compressin of nerve roots
visualized
–Helpful in diagnoses of herniated discs and spinal cord
tumor

94. PATIENTPREPARATION
•Inpatient procedure/ 23HR
•Consent form
•NPO 4-8 hoursprior
•Probably mild sedation given; IVstarted
•Lumbar puncture in radiologyCSFaspirated
•Either water based (Amipaque) or oil based (Pantopaque) dye used
–Hold phenothiazines (Phenergan), TCA’s, SSRI’s 48hours
•Lower seizurethreshhold
–X-ray tabletilted
•CT performed atend

95. POST-PROCEDURECARE
•Amipaque: not aspiratedabsorbed bybody
–HOB 30-60 degrees for 24hours
•Pantopaque: aspirated at end ofvisualization
–Patient flat for 24 hours (rarelyused)
•Quiet activity, littlestimulation
•Push fluids, monitorI andO,BUN, Creatinine
•BP, RR, pulse temperaturemonitored
•May experience nausea, headacheshould diminish no
Phenergan orCompazine!
•No neck stiffness or confusion shouldoccur

96. EEG
•Amplifies and
recordselectrical
activity inbrain
•Uses:
–Detecting areas of abnormal or absent brain
activity
•Brain tumors, hematomas, seizureactivity
•Determination of brain death in comatose
patient

97. EEG PREPARATION USE OF
EVOKEDPOTENTIALS
•Preparation:
–Avoidance of caffeine prior toexam
–No gels, sprays inhair
–Must be quiet and still aspossible
•EvokedPotentials:
–Auditory, sensory, visual: record brain activity
in response tostimuli
–Diagnostic for variousdisorders

98. ELECTROMYOGRAPHY(EMG)AND NERVE CONDUCTION VELOCITIES(NCV)
•EMG: Needle electrodes inserted into skeletal musclespatient
relaxes and contracts various muscles and action potential
recorded
•NCV: Nerve stimulated with electricalimpulse
•Useful in studying patients with cervical or lumbar disc
disease, myasthenia gravis, muscular dystrophy (LMN
diseases)
•Patient should be taught to expect some mild discomfort

99. LUMBARPUNCTURE
•Insertion of needle into
subarachnoid space
between L2 andS1
•Withdrawal of small
amount CSF for
diagnosticevaluation
•Measurement ofCSF
pressure
–Should not be
performed if evidence
of greatly increased
CSFpressure

100. LUMBARPUNCTURE
•Patient preparation:
No diet or fluid restrictions
Empty bowel and bladderbefore
Careful instructions regarding cooperation duringtest
Signed consentrequire
•Positioning
d

101. LUMBARPUNCTURE
•CSF in three labeledtubes
–Protein andglucose
–Culture
–Blood cellcounts
•Post-procedurecare:
–Prone with pillow under abdomen for 1hr
–Flat in bed 6-24 hours (30degrees)
–Increased fluidintake
–Observe site for swelling,leakage
–Observe for post spinalheadache

102. POST-LUMBAR PUNCTURE HEADACHE
•Most common complication
•CSF leaks from needle track depleted
•Increases when patientupright
•AVOID: use small gauge needle/ keep proneafter
•Treatment: bedrest, analgesics, hydration
–Persistent: Bloodpatch

103. CSF FLUIDANALYSIS
•Pressure: Normal: 70-180 mmH2O (5-15mmHg)
–Increased: SAH, brain tumor, viral meningitis
•Appearance: clear andcolorless
–Bloody: SAH or traumatic tap (willclear)
–Cloudy:infection
–Orange or yellow: RBC breakdown, elevated protein

104. CSF FLUIDANALYSIS
•Cell Count: 0-5 monos and noRBC’s
–Elevated monosinfection, abcess, tumor, infarction, chronic illness
(MS)
–RBC’sSAH or traumatictap
•Protein: 15-45mg/dl
–Lower than plasma because ofBBB
–Elevated: infection, tumor, MS, degenerative braindisease
•Glucose: 50-75mg/dl
–Elevated: DM or diabeticcoma
–Decreased: acute bacterial meningitis,tumor

105. THANK YOU