Understanding_Seizures_Utah_2009

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					Understanding Seizures: It
Is Not Always a Convulsion
     Joseph J. Mistovich, M.Ed, NREMT-P
             Chair and Professor
      Department of Health Professions
        Youngstown State University
              Youngstown, Ohio
            jjmistovich@ysu.edu
          Consciousness
• Reticular activating system
• Cerebral hemispheres
      Etiology of Seizures
• Primary
• Secondary (reactive)
                  Definitions
• Generalized
    – Both cerebral hemispheres
    – ARAS
• Partial
    – One cerebral hemisphere
•   Simple – no loss of cognition
•   Complex – impairment of cognition
•   Convulsive
•   Tonic
•   Clonic
•   Ictal
•   Postictal
           Primary Seizures
• Focal seizures
  – Simple partial
  – Complex partial
• Generalized
  – Convulsive (tonic clonic)
  – Nonconvulsive
• Atonic
        Simple Partial Seizure
• One cerebral hemisphere
• No loss of cognition
• Features
  –   Focal clonic movement
  –   Paresthesias
  –   Visual, auditory or gustatory
  –   Sweating and flushing
  –   Dysphasia
  –   Déjà vu
  –   Unwarranted fear
     Simple Partial Seizure
• Motor signs are ipsilateral
• Jacksonian march
• No postictal state
      Complex Partial Seizure
• Alert and may be responsive to
  surroundings in semiappropriate manner
• Impaired cognitive function
• Amnestic
• Automatisms
  –   Lip smacking
  –   Repeated swallowing
  –   Uttering verbal phrases
  –   Picking at clothing
      Complex Partial Seizure
• Aura
  –   Smell
  –   Taste
  –   Visual hallucination
  –   Intense emotional feeling
• May continue with motor activity
  – Driving car
  – Riding bike
• Postictal state may last for hours
• May progress to generalized seizure
Complex Partial Seizure
Generalized Convulsive Seizure
         (Grand Mal)
• Lose consciousness
• No aura
• Prodrome
  – Brief vague
  – Dysphoric
• Tonic clonic activity (convusive)
Generalized Convulsive Seizure
         (Grand Mal)
• Typical progression
  – Loss of consciousness
  – Hypertonic
  – Tonic clonic (1 to 2 minutes)
  – Sympathetic discharge
  – Postictal state (may persist for hours)
    • Headache
    • Drowsiness
Generalized Convulsive Seizure
         (Grand Mal)
• Hypertonic and tonic force
  – Posterior shoulder dislocation
  – Thoracic spine vertebrae fractures
  – Repeated jaw contractions
    • Tongue biting
    • Buccal injuries
• Dysautonomia
  – Transient apnea
  – Incontinence (urinary more common)
Generalized Tonic Clonic
     Generalized Nonconvulsive
              Seizure
•   Absence (petit mal)
•   Myoclonic
•   Tonic
•   Atonic
   Absence Seizure

• Typical
  – Often childhood onset
       • Adult onset can occur
  –   Sudden cessation of normal conscious activity
  –   Nonconvulsive dissociative state
  –   Persist for few seconds to several minutes
  –   Suddenly terminates
  –   Eye movements, blinking, or automatisms
  –   No aura
  –   No postictal state
  –   Pick up exactly where left off with no awareness
      of event
Absence Seizure
         Absence Seizure
• Atypical
  – More complicated motor signs
  – Inconsistent postictal confusion
            Atonic Seizure
• Focal diminution of muscle tone (limb or
  head)
                       or

• Generalized loss of postural tone in which
  head falls forward and body slumps to
  ground (drop attack)
• Recovery occurs immediately
• No loss or extremely brief loss of
  consciousness
• No postictal state
  Myoclonic-Atonic Seizure
• Brief myoclonic jerk of muscle group
• Followed by atonia
• No postictal state
         Status Epilepticus
• Neuronal injury occurs after 30 minutes
• Tonic-clonic seizure last rarely longer
  than 3 minutes
• Operational definition
  – Continuous seizure lasting longer than 5
    minutes
  – Two discrete seizures with no consciousness
    between seizures
• Require prompt treatment
         Status Epilepticus
• Etiology
  – Medication noncompliance – most
    common
  – Barbituate withdrawal may occur and
    precipitate seizure
• Prolonged status epilepticus
  – Deteriorate to subtle twitching of
    extremities
  – Jerking of eyes
 Primary Seizure Occurrence
• May occur sporadically, randomly, or
  predictably
• Recurrence
  – Awakening
  – Sleep deprivation
  – Emotional or physical stress
  – Alcohol
  – Menses
 Primary Seizure Occurrence
• Triggered by sensory stimuli
  – Visual most common
    • Flashing lights
       – Strobes
       – Television
       – Video games
  – Auditory
  – Gustatory
  – Tactile
  – Startle
Secondary (Reactive) Seizures
• Conditions causing seizure
  – Static (anatomic scarring)
  – Progressive (degenerative cortical
    disorder)
  – Transient (electrolyte imbalance)
 Secondary (Reactive) Seizures
   Metabolic Derangements
• Hypoglycemia (<45 mg/dL)
  – Generalized convulsive and nonconvulsive
    seizures
  – Partial seizures may occur
  – Extreme ages most susceptible
  – Seizures respond to glucose
  Secondary (Reactive) Seizures
    Metabolic Derangements
• Electrolyte disorder
  – Hypernatremia
  – Hyponatermia
  – Hypomagnesemia
  – Hypocalcemia
• Sodium disorder most common
  (hyponatremia most often)
  – Rate of sodium decrease and not the
    magnitude
 Secondary (Reactive) Seizures
   Metabolic Derangements
• Hypercalcemia
  – Reduces neuronal excitability
  – Rarely causes seizures
• Hypocalcemia triggers seizures
  – Renal failure
  – Acute pancreatitis
• Hypomagnesemia
  – Poor nutrition – especially in alcoholic
 Secondary (Reactive) Seizures
   Metabolic Derangements
• Hyperglycemic hyperosmolar
  nonketotic syndrome (HHNS)
  – Partial seizures
  – Partial status may occur
  – Don’t respond to anticonvulsants
    • Rehydrate
    • Reduce BGL
 Secondary (Reactive) Seizures
   Metabolic Derangements
• Thyroid hormones lower seizure
  threshold
  – Graves disease
  – Thyrotoxicosis
  Secondary (Reactive) Seizures
       Infectious Disease
• Independent of febrile mechanism
• CNS infection
  – Meningitis (40% will seize)
  – Encephalitis
  – Cerebral abscess (50% will seize)
  – HIV
• Generalized or partial
  Secondary (Reactive) Seizures
        Drugs or Toxins
• Extensive list of drugs and toxins
  – Side effect
  – Overdose
• View seizure as dire sign of toxicity
 Secondary (Reactive) Seizures
       Drugs or Toxins
• Therapeutic doses triggering seizures
  – Antimicrobials
  – Cardiovascular agents
  – Neuroleptics (antipsychotics)
    • Phenothiazines
    • Dystonic reaction
  – Sympathomimetics
 Secondary (Reactive) Seizures
       Drugs or Toxins
• Most common drug or toxin induced
  seizure
  – Illicit drugs
     • Cocaine
     • Methamphetamine
     • Phencyclidine (PCP)
  – Overdose of anticholinergics
     • Cyclic antidepressants
     • Antihistamines
 Secondary (Reactive) Seizures
       Drugs or Toxins
• Most common drug or toxin induced
  seizure
  – Withdrawal
    • Alcohol
    • Sedatives-hypnotics
  – Toxic levels and deliberate overdose
    •   Aspirin
    •   Theophylline
    •   Lithium
    •   Dilantin
    •   Carbamazepine
         Cocaine Toxicity
• Seizure following
  – Isolated recreational use
  – Chronic abuse
  – Overdose
  – “Body packers” and “body stuffers”
• Seizure may result from
  – Direct CNS toxicity
  – Hypoxia from cardiac toxicity
         Cocaine Toxicity
• Seizures usually accompanied with
  – High fever
  – Rhabdomyolysis
  – Cardiac dysrhythmias
• Stop seizure with a benzodiazepine
             Ethyl Alcohol
• Common toxic etiology of seizure
  – Acute inebriation
  – Alcohol withdrawal (more common)
    • Generalized and recurrent
    • May begin within 6 hours after cessation or
      decrease consumption of alcohol
    • Look for other organic causes
    • Treat with benzodiazepine
       – Replace GABA enhancing effects of alcohol
             Ethyl Alcohol
• Kindling
  – seizure threshold lowers with each
    withdrawal episode
  – Risk and severity of seizure increases
    with each withdrawal episode
               Trauma
• Blunt or penetrating head injury
• Acute episode
  – Epidural hematoma
  – Subdural hematoma
  – Intracerebral hematoma
  – Subarachnoid hemorrhage
• Onset most often delayed several
  hours
                 Trauma
• Early post-traumatic seizures occur
  within 1 week
• Late post-traumatic seizures occur
  after 1 week
• Seizures more common in children
  – More likely to present in status
    epilepticus
                 Stroke
• Ischemic or hemorrhagic stroke
  – Cause of new onset seizures in 40 to 54%
    of the elderly
  – Overall incidence is 4 to 15%
  – >50% occur within first week post-stroke
  – Incidence of epilepsy post-stroke is 4 to
    9%
                  Stroke
• Acute seizures with stroke
  – Local metabolic alterations in CNS
  – Transient
  – Focal seizures
  – Self-limited
• Late seizure with stroke
  – Generalized
        Other CNS Causes
• Unruptured AVM or aneurysm
• Vascular headache or migraine
  – Infarct creates epileptic focus
  – Triggers an existing epileptic focus
         Gestational Seizures
• Gestational epilepsy
  – Hormonal and metabolic changes
       • Exacerbate underlying epilepsy
       • Adversely influence serum levels of anticonvulsants
• Eclampsia (Toxemia)
  –   HTN
  –   Proteinuria
  –   Edema
  –   Magnesium sulfate is drug of choice
• Generalized convulsive seizures jeopardize
  mother and fetus
    Psychogenic Nonepileptic
           Seizures
• Pseudoseizures
  – AMS
  – Abnormal movements or behavior
  – Generalized convulsive
  – Generalized absence
  – Partial complex
• Can occur with true seizures
          Postictal States
• May persist for minutes to hours
  – Decreased arousal and responsiveness
  – Disorientation
  – Amnesia
  – Headache
• Postictal state is not consistent from
  seizure to seizure
            Postictal States
• Management
 – Airway
   • Manual maneuver
   • Lateral recumbent
 – Obtain SpO2
 – Determine BGL
 – Continuous cardiac monitoring
         Postictal Paralysis
         (Todd’s paralysis)
• Follow generalized or complex partial
  seizure
• Focal motor deficit
  – Weakness of one extremity
  – Complete hemiparesis
• May persist up to 24 hours
• High likelihood of underlying
  structural lesion
  Neurogenic Pulmonary Edema
• Relatively common but often subclinical
  –   SpO2
  –   Ausculation of breath sounds
  –   Signs of hypoxia
  –   Respiratory distress
• Sympathetic discharge
  – Generalized vasoconstriction
  – Increase pulmonary capillary permeability
• Often mistaken for aspiration pneumonia
• Manage with CPAP or PPV with PEEP
           Management
• Airway management
 – Gag reflex is suppressed during ictus
 – Vomiting with aspiration
 – Lateral recumbent position
 – Remove dentures
 – Consider endotracheal intubation
   • Persistent seizure
   • Induce with benzodiazepine
             Management
•   SpO2 to guide oxygen therapy
•   PPV if necessary
•   Continuous ECG monitor
•   EtCO2 monitor
•   IV line of NS TKO
            Management
• Benzodiazepine
  – Enhances GABA in neurons
    • Diazepam (Valium)
    • Lorazepam (Ativan)
    • Midazolam (Versed)
  – Use in patients of any age
  – Rapid onset (seconds to minutes)
  – Short duration
  – Potential for hypotension and respiratory
    depression
       Lorazepam (Ativan)
• Drug of choice
  – Terminates seizure within 2 minutes
  – Longer duration of action ( 4 to 6 hours)
  – Can be given IM or IV
  – Must be refrigerated or reconstituted
  – Dose
    • 0.1 mg/kg IV (4 mg in adult)
    • Repeat in 10 minutes
    • 0.01 -0.1 mg/kg per hour infusion
       Diazepam (Valium)
• Liquid form in room temperature
  – Easily carried by EMS for long periods
  – Rectal gel
  – IV onset is 10 to 20 seconds
  – 50% chance of recurrent seizure within 2
    hours
  – Dose
    • 5 to 10 mg every 10 minutes up to 30 mg in 8
      hour period
    • Rectal in pediatrics at 0.3 to 0.5 mg/kg
         Midazolam (Versed)
•   Onset of action is 1 minute
•   Can be administered intranasally
•   Has the least cardiovascular effects
•   Dose
    – 0.2 mg/kg bolus (don’t exceed 2.5 mg)
    – 0.05 – 0.6 mg/kg per hour infusion
    – 0.2 mg/kg intranasally
 Presentation was adapted from
“Primary Seizures in Adults” Marx:
Rosen’s Emergency Medicine, 7th
  edition, www.mdconsult.com,
           Mosby 2009