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Front Back
Neurologic
Disorders
Into to Med/Surg
Linton/Saunders
Chap 27 p415-459
KEY



Δ
Ø

á
A&P

Neurons
Axons
Branches that conducts impulses away from cell body
A&P

Neurons
Dendrites
Branches that convey impulses towards cell body
A&P

Neurons
Conduct electrical impulses within the nervous system

Types:
Afferent
Efferent
A&P

Afferent Neurons
AKA:
Sensory Neurons

Function:
...Transmit info from distal parts of body or environment towards CNS
A&P

Efferent Neurons
AKA:
Motor Neurons

Function:
...Transmits info from CNS to periphery
A&P

Neurons
Depolarization
During impulse transmission, when dendrite stimulated

Na+ & K+ exhanged
A&P

Neurons
Repolarization
During impulse transmission, after dendrite stimulated, impulse continues to axon

Ions return to resting state
A&P

Neurotransmitters
Impulses passed across neural synapses, then reaches the end of axon, biochemical messengers are released

Types of Neurotransmitters:
Acetylcholine
Norepinephrine
Epinephrine
Dopamine
A&P

Central
Nervous System
Brain & spinal cord
A&P

Peripheral
Nervous System
All peripheral nerves
Spinal nerves
Cranial nerves
A&P
PNS

Autonomic
Part of Peripheral Nervous System

Helps homeostasis

Controls involuntary activities of organs

Subdivided into
Sympathetic
Parasympathetic
A&P
PNS

Sympathetic
Fight or flight response

Secretes epinephrine & norepinephrine

Increase HR, constricts blood vessels so increase BP

aka Thoracolumbar System


A&P PNS

Parasympathetic
Rest response

Decrease HR & BP

aka Craniosacral System
Age Related
Changes
Decrease:
Nerve Cells
Brain Weight

Increase:
Ventricles
Plaques & Tangles around nerve tissues

Deposited in nerve cells:
Lipofuscin = aging pigment
Amyloid = protein

Physical Exam:
Pupils smaller, slow response
Eyes jerky movements
Reflexes intact but Achilles absent
Reaction time increases
Pathophysiology
Development
...structural, hydrocephalus

Trauma
...CNS injuries, physical, chemicals

Infections/Inflammation
...meningitis, encephalitis

Neoplasms
...CBS tumors

Degenerative
...Alzheimers, MS, Parkinsons, Huntingtons

Vascular
...decrease blood flow => cell death => loss of function

Metabolic/Endorcine
...Brain needs glucose so glucose & electrolyte imbalance => impaired throught process, LOC
...rt accumulated toxins, poison, renal/liver failure
Physical Exam

Neuro Checks
LOC: somnolence. lethargy. stupor. semicoma. coma

A&O x4: person. place. time. situation

Response to stimulation: verbal. tactile. pain.

Pupils: PERRLA. Norm = 3mm round react briskly to light

Neuromuscular: Evaluates cerebral & spinal cord function via elicit motor responses

VS: late indicator but reliable info. HR. RR. BP.
Diagnostics

Cranial Nerves
1 Olfactory: smell

2 Optic: Vision

3 Oculomotor: Eyes move circular, PERRLA, raises eyelids

4 Trochlear: Eyes move down & in

5 Trigeminal: Hot/Cold sensation, touch, chew (ophthalmic, maxillary, mandibular)

6 Abducens

7 Facial

8 Acoustic

9 Glossopharyngeal

10 Vagus

11 Spinal Accessory

12 Hypoglossal
Diagnostics

Advance Neuro Exam
Cranial Nerves

Coordination & Balance

Neuromuscular Function

Sensory Fuction

Reflexes
Theraputic Measures

Drug Theraphy
Antimicrobials
Analgesics
Antiinflamatory
Chemo
Dopaminergics
Anticholinergics
Cholinergics
Antihistamines
Theraputic Measures

Surgery
Craniotomy
surgical opening of skull

Tx For:
tumors
correct defects
evacuate hematomas
relieve pressure rt trauma

Craniectomy
Excision of a segment of the skill

Cranioplasty
Repair skull defect
Theraputic Measures

Surgery
Preop Nsg Care
  • Document baseline neuro status
  • Encourage pt communication
  • If cerebral edema, parenteral corticosteroids may be ordered
  • Shave hair per procedure
  • Pt support rt hair
  • Family support
Theraputic Measures

Surgery
Postop Nsg Care
  • Monitor LOC, VS, Neuro checks, I&O
  • Report deteriorating neuro status
  • SSx rt complications: HA, visual disturbance, N&V, seizures, resp depress
  • Drainage from ears, nose...
  • Dressing: CSF pink stain surrounded by lighter rink aka "halo"
  • External Ventricular Drainage System: aseptic techique, 0 reference point of drip chamber per order or EAC
Theraputic Measures

Surgery
Postop Complications
Increased ICP
CSF Leak
Meningitis
Seizures

Others depend of area affected:
Paralysis
Memory loss
Confusion
Impaired Speech
Vision
Hearing
Increased
Intracranial Pressure

Pathophysiology
  • Cranial cavity contains brain, blood, CSF
  • Contents exert pressure in cranium at 0 -15mmHg
 
Increased
Intracranial Pressure

Monro - Kellie Hypothesis
Adaptations of brain, blood, and CSF for ICP to remain normal

Volume of one component increases another component must decrease or ICP occurs

Example:
Brain tumor increase volume of brain tissue so blood & CSF must decrease to maintain balance

CPP Cerebral Perfusion Pressure
MAP Mean Arterial Pressure
ICP Intracranial Pressure

CPP = MAP - ICP
Increased
Intracranial Pressure

Signs & Symptoms
LOC
...Most reliable. Early sign. Subtle: Minimal agitation, drowsiness. Extreme: Unresponsive

Motor Function
...frontal lobe pressure, deficits may be contralateral, hemiparesis, hemiplegia

Posture
...occurs spontaneously or with pain stimuli. Pressure on cerebral tissue causes decorticate (abnormal flexion). Pressure on midbrain or upper pons causes decerebrate (abnormal extension)

Hypothalamic
...pressure on perihypothalamus tissure disables bodys temp regulation

Pupils
...Late sign. Increase ICP = dilated, fix, 0 response to light.

Vital Signs
...Late sign. Cushings triad (HTN. Bradycardia. Wide pulse pressure)
Increased
Intracranial Pressure

Treatments
Prompt Tx vital for survival

Position 30° for venous blood flow from brain Ξ decrease ICP (jugular)

Controlled Hyerventilation for 1-2mins via mechanical vent to eliminate CO2 effective for 36-48hrs (r/t ↑ CO2 → dilated cerebral blood vessesl Ξ ↑volume & ICP. Later options for Tx.)

Adequate Fluids for CPP. Pt with Cardiac Hx, moitor fluid overload

Ventriculostomy Cath drains excess CSF via gravity drainage. Absolute aseptic needed.

IV mannitol, hyperosmolar diuretic that draws edema fluid from tissues spaces into bloodstream → eliminated via kidneys. Also, furosemide.

Corticosteroids ↓edema

Dexamethason
Disorders

Headache
Abbreviated: HA

Most common type of pain

More of a symptom than a disease

4 Common Types:
Migrane
Cluster
Tension
HA r/t eyes, teeth, sinus disorders
Disorders

Headache
Migrane
Due to intracranial vasoconstriction followed by vaso dilation

Triggered by menses, ovulation, etoh, stress, some foods

Signs&Symptoms
Depression
Irritability
Visual Disturbance
Paresthesia á pain Treatments
Prevent triggers
Rx: Mild= ASA, Acetaminophen. Severe= Ergotamine, Sumatriptan
Disorders

Headache
Clusers
May be r/t stress, anxiety

Signs&Symptoms
Series of episodes followed by long period c Ø sx

Intense pain s warning sx

Treatments
Cold applications
Rx: Indomethacin, Tricylic Antidepressants
Disorders

Headache
Tension
Results from prolonged muscle contractions.

r/t anxiety, stress, brain tumor. abcessed tooth

Persist from days to years

Signs&Symptoms
Pain varies c location
N&V
Dizziness
Tinnitus
Tearing

Treatments
Correct known causes
Psychotheraphy
Massages
Heat application
Relaxation techniques
Nonopioid analgesics
Disorders

Seizures
Electrical impulses conducted in highly chaotic pattern Ξ abnormal activity & behavior Involves many hyperactive neurons that use excessive O2 & glucose

r/t trauma, ↓cerebral perfusion, infection, electrolyte disturbances, poisoning, tumors
Disorders

Partial Seizures
aka Focal Seizures

Abnormal activity in specific area of brain, fairly localized, & stop

Progression to entire brain is known as Partial seizures c secondary generalization

Simple
Conscious
SSx: motor, somatosensory, autonomic, psychic

Complex
Consciousness impaired
SSx: bizarre, repetitive behavior 
Disorders

Generalized Seizures
Involves entire brain from onset c consciousness lost

Tonic-Clonic
Absence
Myoclonic
Atonic
Disorders

Status Epilepticus
Continous seizures or repetitive seziures in rapid succession for 30+ mins.

Oxygen & glucose is depleted in brain
Disorders

Seizures
Auras
Sensations preceding a seizure such as

dizziness
numbness
visual/hearing disturbance
perception of offensive odor
pair
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