Transcript Training

Nervous System Emergencies
Nervous System A & P

Nervous System Basics
 The
body’s control system
 Exerts control through electrochemical
impulses transmitted through nerves
 Three subdivisions
Central nervous system (brain and spinal cord)
 Peripheral nervous system (cranial, peripheral
nerves)
 Autonomic nervous system (sympathetic,
parasympathetic)

Nervous System A & P

A & P of CNS (brain and spinal cord)
 Neuron-nerve
cell; fundamental component of
the nervous system
Cell body contains nucleus
 Dendrites carry nervous impulses to cell body
 Axons transmit nerve impulses away from cell body
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Nervous System A & P

A & P of CNS (brain and spinal cord)
 Transmission
of impulses in the nervous system
At rest, neuron is positively charged outside,
negatively charged inside
 When stimulated, sodium enters cell, potassium
rapidly leaves cell
 Activity produces positive charge, called action
potential, at entry site
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Nervous System A & P Overview

A & P of CNS (brain and spinal cord)
 Transmission
of impulses in the nervous system
(cont.)
Action potential transmitted down neuron to meet
other neurons at junctions called synapses
 Axon releases neurotransmitter (acetylcholine or
norepinephrine) that transports impulses across
synapse and stimulates connecting nerve
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Nervous System A & P Overview

Protective structures of the CNS
 Mostly
protected by body structures (skull,
spinal column)
 Also covered by membranes - meninges (pia,
arachnoid, dura)
 Brain and spinal cord also bathed in
cerebrospinal fluid (CSF)
Nervous System A & P Overview

The brain
 Cerebrum
 Diencephalon
 Mesencephalon
 Pons
 Medulla
Oblongata
 Cerebellum
Nervous System A & P Overview

Cerebrum
 Two
hemispheres joined by corpus callosum
 Governs all sensory and motor functions
 Responsible for language, learning, analysis,
memory
 Cerebral cortex is outermost layer
Nervous System A & P Overview

Diencephalon
 Superiormost
portion of brain stem
 Contains thalamus, hypothalamus, limbic
system
 Responsible for involuntary actions
 Major role in regulating autonomic nervous
system
Nervous System A & P Overview

Mesencephalon
 Midbrain-located
between mesencephalon and
pons
 Responsible for motor coordination and eye
movement
Nervous System A & P Overview
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Pons
 Located
between midbrain and medulla
 Contains connections between the brain and
spinal cord
Nervous System A & P Overview
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Medulla Oblongata
 Located between pons and spinal cord
 Marks division between brain and spinal cord
 Controls respirations, cardiac function ,
vasomotor activity
Nervous System A & P Overview
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Cerebellum
 Located
in posterior fossa of cranial cavity
 Coordinates fine motor movement, posture,
equilibrium, muscle tone
Nervous System A & P Overview

Areas of Specialization
 Speech-temporal
lobe
 Vision-occipital lobe
 Personality-frontal lobes
 Balance and coordination-cerebellum
 Sensory-parietal lobes
 Motor-frontal lobes
Nervous System A & P Overview

Vascular supply to brain
 Supplied
by two systems: carotid system and
vertebrobasilar system
 Both join at the circle of Willis before entering
brain
 Interruption of one system will not seriously
affect brain perfusion
 Venous drainage through venous sinuses and
internal jugular veins
Nervous System A & P Overview

Spinal Cord
 17-18
inches long
 Leaves the brain through the foramen magnum
 Conducts impulses to peripheral nervous
system
 Conducts sensory impulses to the brain and has
reflex arc capability
Nervous System A & P Overview

Spinal Cord (cont.)
 Has
31 pairs of nerve fibers
Dorsal roots contain afferent fibers (body to brain)
 Ventral roots contain efferent fibers (brain to body)
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 Nerve
fibers innovate corresponding body areas
called dermatones
Nervous System A & P Overview

A & P of the peripheral nervous system
 Basic
information
Consists of cranial and peripheral nerves
 Has both voluntary and involuntary components
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Nervous System A & P Overview

A & P of the peripheral nervous system
 Categories
of the peripheral nerves
Somatic motor-carry impulses to skeletal muscles
 Visceral sensory-transmit sensations from visceral
organs (e.g., full bladder need to defecate, etc.)
 Somatic sensory-transmit sensations of touch,
pressure, pain, temperature, position
 Visceral motor-supply nerves to visceral glands and
organs
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Nervous System A & P Overview
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Autonomic nervous system
 Responsible
for unconscious control of body
functions
 Made up of two antagonistic, but normally
balanced parts
Sympathetic nervous system controls stress response
 Parasympathetic nervous system controls custodial
(vegetative) functions
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Assessment of the Neurological
System
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Primary Assessment
 First
check for responsiveness
 Place emphasis on airway maintenance and
cervical spine stabilization
 With unconscious patients assume cervical
spinal injury

Use modified jaw thrust maneuvers
 Remain
alert for possibility of respiratory arrest
Assessment of the Nervous
System
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Secondary Assessment
 History
Determine trauma vs medical etiology
 If trauma
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When did incident occur
Mechanism of injury
Any loss of consciousness
Chief complaint
Complicating factors
Assessment of the Nervous
System
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Secondary Assessment (cont.)
 History

(cont.)
If nontrauma
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Chief complaint
History of present illness
Pertinent underlying medical problems (cardiac disease,
hypertension, diabetes, seizures)
Environmental clues (medications, Medic-alert ID, alcohol
or drug bottles)
Assessment of the Nervous
System
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Head to toe survey
 Pupils
Check eye movement and pupil reaction
 Early indicators of increasing ICP
 Cardinal positions of gaze
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Fixed, midsize pupils-midbrain
Pinpoint pupils, barely reactive-pons
Unilateral fixed and dilated pupil-third nerve
Fixed or asymmetric pupils-structural lesions
Nonreative pupils-toxic/metabolic states
Assessment of the Nervous
System
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Head to toe survey (cont.)
 Pupils
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(cont.)
Extraocular movements
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Disconjugate gaze-structural brainstem lesion
Doll’s eyes-brainstem dysfunction
Assessment of the Nervous
System
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Head to toe survey (cont.)
 Respiratory
derangements common with CNS
illness or injury
Cheyne Stokes respiration-period of apnea followed
by increasing depth and frequency of respirations
 Central neurogenic hyperventilation-rapid, deep,
noisy respirations; lesion in CNS
 Ataxic respirations-ineffective thoracic muscular
coordination due to CNS damage
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Assessment of the Nervous
System
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Head to toe survey (cont.)
 Respiratory
derangements common with CNS
illness or injury (cont.)
Apneustic respirations-prolonged inspiration
unrelieved by expiration attempts; damage to upper
pons
 Diaphragmatic breathing-caused by intercostal
muscle dysfunction
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Assessment of the Nervous
System
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Spinal Evaluation-document loss of motor
function or sensation
 Evaluate
for pain and tenderness
 Observe for bruises
 Observe for deformity
 Check for motor, sensory and position in each
extremity and bilateral grip strength
 Determine response to pain
 Note any incontinence
Assessment of the Nervous
System
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Vital signs that characterize CNS injury
 Increased
blood pressure
 Decreased pulse
 Decreased respirations
 Increased temperature
Assessment of the Nervous
System

Neurological Evaluation - provides baseline
neurological findings for later
comparison/contrast
 Determine

level of consciousness
AVPU during primary survey
 Note
sensation and motor function in
extremities
Asymmetry-structural lesions
 Abnormal posturing
 Flaccid paralysis-spinal cord injury
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Assessment of the Nervous
System
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Glascow Coma Scale
 Evaluates
coma patient with CNS injury by
monitoring
Eye openings
 Verbal response
 Motor response
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Nervous System Emergencies
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Altered mental status-hallmark of CNS
illness or injury
 Basic
mechanisms that can produce altered
mental status
Structural lesions
 Toxic-metabolic states
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Nervous System Emergencies
 Common
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causes of altered mental status
Structural
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Trauma
Brain tumor
Epilepsy
Intracranial hemorrhage
Other space-occupying lesions
Nervous System Emergencies
 Common
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causes of altered mental status
Metabolic
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Anoxia
Hypoglycemia
Diabetic ketoacidosis
Hepatic failure
Renal failure
Thiamine deficiency
Nervous System Emergencies

Common causes of altered mental status
 Drugs
Barbiturates
 Narcotics
 Hallucinogens
 Depressants
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Nervous System Emergencies
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Common causes of altered mental status
 Cardiovascular
Hypertensive encephalopathy
 Shock
 Anaphylaxis
 Dysrhythmias
 Cardiac arrest
 CVA
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Nervous System Emergencies

Common causes of altered mental status
 Respiratory
COPD
 Toxic gas inhalation
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 Infectious
Encephalitis
 Meningitis
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Nervous System Emergencies
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Primary Assessment
 Special
attention to the airway and c-spine
 Consider AEIOU TIPS mnemonic
 Early intubation
Nervous System Emergencies

Secondary Assessment
 History
Length of alteration in mental status
 Onset
 History of recent head trauma
 patient under medical care
 Alcohol or drug use
 Preceding symptoms or complaints
 Any medications
 Medic-Alert tags

Nervous System Emergencies
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Secondary Assessment (cont.)
 Physical
exam-should include breathing,
response to stimuli, eye response, pupil
response, being particularly alert in suspected
CNS illness or injury cases
Pupillary reflexes-fixed, dilated, or asymmetric
pupils
 Extraocular movements-dysconjugate gaze
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Nervous System Emergencies
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Secondary Assessment (cont.)
 Physical
exam-should include breathing,
response to stimuli, eye response, pupil
response, being particularly alert in suspected
CNS illness or injury cases
Motor findings-asymmetry, decorticate or decebrate
posturing, flaccid paralysis
 Respiratory patterns
 Vital signs-hypertension, bradycardia, unusual body
temperature
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Nervous System Emergencies
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Management
 Immobilization
of the cervical spine
 Assure patency and adequate breathing
 Draw venous blood sample, check blood sugar
with glucometer or chem strip
 IV 5% D5W at TKO rate; related NS or LR if
trauma
 Cardiac monitor
Nervous System Emergencies

Drug considerations
 50mL
of 50% dextrose (25 grams) IV to correct
hypoglycemia
 Naloxone 1-2 mg IV to reverse narcotic
overdose
 Thiamine 100mg IV to correct thiamine
deficiency and allow glucose metabolism
 Mannitol 25g IV to reduce ICP
 Decadron 4-24 mg IV to reduce cerebral edema
Nervous System Emergencies

Management with chronic alcoholism
 Many
have thiamine deficiency
Wernicke’s syndrome-memory loss, disorientation
 Korsakoff’s psychosis-disorientation,m muttering
delirium, insomnia, delusions painful extremities,
bilateral foot drop, pain on pressure over long
nerves
 These patients should receive 100 mg Thiamine IV
or IM
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Nervous System Emergencies
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Management with ICP
 Hyperventilate
patient
 Decadron 4-24 mg IV to reduce cerebral edema
 Mannitol 25g IV to cause an osmotic diuresis
Nervous System Emergencies
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Seizures
 Pathophysiology
of seizures
Massive electrical discharge of one or more groups
of neurons in the brain
 Can be general or partial
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Generalized seizures-grand mal and petit mal
Partial seizures-simple or complex (psychomotor)
Nervous System Emergencies
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Seizures (cont.)
 Causes
of seizures
Stressors such as hypoxia, sudden elevation in
temperature, or hypoglycemia in healthy persons
 Structural diseases such as tumors, head trauma,
eclampsia, vascular disorders
 Idiopathic epilepsy is the most common cause
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Nervous System Emergencies
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Seizures (cont.)
 Types

of Seizures
Grand Mal-generalized motor seizure
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Produces loss of consciousness from brain hypoxia
Causes uncontrollable tonic/clonic movements of
extremities
Disrupts respirations, producing cyanosis
Often lead to frothing, incontinence, mental confusion
Coma or drowsiness follows (postical period)
Nervous System Emergencies
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Seizures (cont.)
 Grand-mal
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(progression)
Aura-subjective sensation preceding seizure
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May be psychic (déjà vu)
May be sensory (a noise, sight, sound, odor)
Loss of consciousness
 Tonic phase-continuous motor tension and
contraction of muscles
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Nervous System Emergencies

Seizures (cont.)
 Grand-mal
(progression cont.)
Hypertonic phase-extreme muscular rigidity,
hyperextension of the back
 Clonic phase-extreme muscular rigid
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Nervous System Emergencies

Seizures (cont.)
 Grand-mal
(progression cont.)
Post-seizure coma
 Postictal period-patient awakens confused, fatigued
with some neurological deficits
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Nervous System Emergencies
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Seizures (cont.)
 Focal
motor seizures
Characterized by dysfunction of one area of the
body
 Caused by electrical discharge form one part of the
brain
 Begin as localized tonic/clonic movements; can
spread and appear s generalized
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Nervous System Emergencies
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Seizures (cont.)
 Psychomotor
(temporal lobe) seizures
Characterized by distinctive pre-seizure aura
 Focal seizures lasting 1-2 minutes
 Patient experiences loss of contact with
surroundings
 Patient may be confused, purposeless, or may show
change in personality or rage abruptly
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Nervous System Emergencies
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Seizures (cont.)
 Petit
mal seizures
Generalized seizures with 10-30 second loss of
consciousness
 Patient may stare and flutter eyelids
 Observers may be unaware of seizure
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Nervous System Emergencies
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Seizures (cont.)
 Hysterical
seizures
Psychological disorders
 Patient presents with sharp and bizarre movements
 Curt commands can curtail seizure
 No postical period
 Use of aromatic ammonia may differentiate
hysterical from true seizure
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Nervous System Emergencies

Assessment
 rule
out other causes of coma
 Obtain history including:
History of seizure
 Alcohol/drug abuse
 Current medications
 Recent history of head trauma
 Description of seizure
 Past medical history (diabetes, cardiac, strokes)
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 Differentiate
true seizure vs. syncope
Nervous System Emergencies

Management
 Protect
patient from self-harm; do not restrain
 Maintain airway
 Administer oxygen
 Establish IV access
 Determine blood glucose; D50W if needed
 Protect body temperature
 position patient on side after tonic/clonic phase
Nervous System Emergencies

Management (cont.)
 Suction
if required
 Monitor cardiac rhythm
 Provide quiet rest, reassuring atmosphere
 Transport in supine or lateral recumbent
position
Nervous System Emergencies

Status Epilepticus
 Description
Series of two or more seizures without lucid period
 Most common cause is failure to take anticonvulsant
medications
 Can lead to brain injury from anoxia
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Nervous System Emergencies

Status Epilepticus (cont.)
 Management
Establish and protect airway
 Assist ventilations with 100% oxygen
 Establish IV access with NS TKO
 Monitor cardiac rhythm
 Administer 50% dextrose 25gm IV
 Administer diazepam 5-10 mg IV
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Nervous System Emergencies

Stroke (cerebrovascular accident - CVA)
 Pathophysiology
injury or death to brain tissue from interruption of
blood
 Can by caused by ischemic or hemorrhagic lesions
commonly secondary to atherosclerosis or
hypertension
 Sudden loss of consciousness followed by paralysis
which may be caused by hemorrhage, embolism or
thrombus
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Nervous System Emergencies

Strokes (cont.)
 Categories
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Infarction
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of stroke
Inadequate blood supply to limited prtion of the brain
caused by embolism or blood vessel occlusion usually due
to thrombus
Hemorrhage
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Intracerebral or subarachnoid bleeding
Marked by sudden onset of headache and stiff neck
Can cause increased intracranial pressure
Nervous System Emergencies

Strokes (cont.)
 Clinical
presentation of a stroke
Symptoms depend on area of brain injured
 Motor, speech, and sensory centers most commonly
affected
 Onset of symptoms is acute and may include:
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Unconsciousness
Stertorous breathing
Unequal pupils
Unilateral paralysis
Speech disturbances
Nervous System Emergencies

Strokes (cont.)
 Distinguishing
CVA from transient ischemic
attacks (TIA’s)
Temporary stroke symptoms
 Usually caused by small emboli
 Can last several minutes to hours
 No evidence of neurological deficient after attack
 Abrupt onset with symptoms depending on area of
brain affected
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Nervous System Emergencies

Strokes (cont.)
 Symptoms
Monocular blindness
 Hemiplegia
 Inability to recognize by touch
 Staggering
 Difficulty in swallowing, aphasia
 Hemiparesis
 Dizziness
 Numbness, paresthesia
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Nervous System Emergencies

Strokes (cont.)
 History
- Determine:
Previous neurological symptoms
 Initial symptoms and their progression
 Chanbes in mental status Precipitating factors
 Dizziness
 Palpitations
 History of hypertension, cardiac disease, sickle cell
disease, previous TIA or stroke
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Nervous System Emergencies

Strokes (cont.)
 Physical
Exam - Be alert for:
Hemiparesis, hemiplegia
 Unilateral facial droop
 Speech disturbances
 Gait problems
 Altered mental status
 Vision problems
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Nervous System Emergencies

Strokes (cont.)
 Management
of CVA and TIA
Maintain patient supine with 15 degree head
elevation to maximize venous drainage
 Maintain c-spine integrity if trauma suspected
 Maintain a patent airway, assisting ventilation PRN
 Administer oxygen, hyperventilation if patient
unresponsive
 Draw venous blood sample and test for blood sugar

Nervous System Emergencies
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Strokes (cont.)
 Management
Start IV with NS or LR TKO
 Monitor cardiac rhythm
 If patient hypoglycemic, give D50W
 Protect paralyzed extremities
 Reassure patient and transport quietly to hospital

Nervous System Emergencies
Judy Dyke, RN, NREMT-P
Rogers State University
Paramedic Technology Program