Nervous System Emergencies

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Nervous System Emergencies
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Nervous System A P

• Nervous System Basics
• The bodys 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)

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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)

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Nervous System A P Overview

• The brain
• Cerebrum
• Diencephalon
• Mesencephalon
• Pons
• Medulla Oblongata
• Cerebellum

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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

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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

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Nervous System A P Overview

• Mesencephalon
• Midbrain-located between mesencephalon and pons
• Responsible for motor coordination and eye
  movement

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Nervous System A P Overview

• Pons
• Located between midbrain and medulla
• Contains connections between the brain and spinal
  cord

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Nervous System A P Overview

• Medulla Oblongata
• Located between pons and spinal cord
• Marks division between brain and spinal cord
• Controls respirations, cardiac function ,
  vasomotor activity

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Nervous System A P Overview

• Cerebellum
• Located in posterior fossa of cranial cavity
• Coordinates fine motor movement, posture,
  equilibrium, muscle tone

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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

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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

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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

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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)
• Nerve fibers innovate corresponding body areas
  called dermatones

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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

• 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

• 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

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Assessment of the Nervous System

• Secondary Assessment
• History
• Determine trauma vs medical etiology
• If trauma
• When did incident occur
• Mechanism of injury
• Any loss of consciousness
• Chief complaint
• Complicating factors

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Assessment of the Nervous System

• Secondary Assessment (cont.)
• History (cont.)
• If nontrauma
• 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)

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Assessment of the Nervous System

• Head to toe survey
• Pupils
• Check eye movement and pupil reaction
• Early indicators of increasing ICP
• Cardinal positions of gaze
• 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

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Assessment of the Nervous System

• Head to toe survey (cont.)
• Pupils (cont.)
• Extraocular movements
• Disconjugate gaze-structural brainstem lesion
• Dolls eyes-brainstem dysfunction

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Assessment of the Nervous System

• 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

• 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

• 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

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Assessment of the Nervous System

• Vital signs that characterize CNS injury
• Increased blood pressure
• Decreased pulse
• Decreased respirations
• Increased temperature

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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

• Glascow Coma Scale
• Evaluates coma patient with CNS injury by
  monitoring
• Eye openings
• Verbal response
• Motor response

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Nervous System Emergencies

• 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 causes of altered mental status
• Structural
• Trauma
• Brain tumor
• Epilepsy
• Intracranial hemorrhage
• Other space-occupying lesions

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Nervous System Emergencies

• Common causes of altered mental status
• Metabolic
• Anoxia
• Hypoglycemia
• Diabetic ketoacidosis
• Hepatic failure
• Renal failure
• Thiamine deficiency

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Nervous System Emergencies

• Common causes of altered mental status
• Drugs
• Barbiturates
• Narcotics
• Hallucinogens
• Depressants

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Nervous System Emergencies

• 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
• Infectious
• Encephalitis
• Meningitis

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Nervous System Emergencies

• Primary Assessment
• Special attention to the airway and c-spine
• Consider AEIOU TIPS mnemonic
• Early intubation

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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

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Nervous System Emergencies

• 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

• 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

• 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

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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

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Nervous System Emergencies

• Management with chronic alcoholism
• Many have thiamine deficiency
• Wernickes syndrome-memory loss, disorientation
• Korsakoffs 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

• Management with ICP
• Hyperventilate patient
• Decadron 4-24 mg IV to reduce cerebral edema
• Mannitol 25g IV to cause an osmotic diuresis

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Nervous System Emergencies

• Seizures
• Pathophysiology of seizures
• Massive electrical discharge of one or more
  groups of neurons in the brain
• Can be general or partial
• Generalized seizures-grand mal and petit mal
• Partial seizures-simple or complex (psychomotor)

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Nervous System Emergencies

• 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

• Seizures (cont.)
• Types of Seizures
• Grand Mal-generalized motor seizure
• 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)

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Nervous System Emergencies

• Seizures (cont.)
• Grand-mal (progression)
• Aura-subjective sensation preceding seizure
• 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

• 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

• 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

• 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

• 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)
• Differentiate true seizure vs. syncope

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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

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Nervous System Emergencies

• Management (cont.)
• Suction if required
• Monitor cardiac rhythm
• Provide quiet rest, reassuring atmosphere
• Transport in supine or lateral recumbent position

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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 of stroke
• Infarction
• Inadequate blood supply to limited prtion of the
  brain
• caused by embolism or blood vessel occlusion
  usually due to thrombus
• Hemorrhage
• Intracerebral or subarachnoid bleeding
• Marked by sudden onset of headache and stiff neck
• Can cause increased intracranial pressure

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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
• Unconsciousness
• Stertorous breathing
• Unequal pupils
• Unilateral paralysis
• Speech disturbances

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Nervous System Emergencies

• Strokes (cont.)
• Distinguishing CVA from transient ischemic
  attacks (TIAs)
• 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

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Nervous System Emergencies

• 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

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Nervous System Emergencies

• Judy Dyke, RN, NREMT-P
• Rogers State University
• Paramedic Technology Program