Neonatal Seizures Neonatal Seizures Amy Kao M

					Neonatal Seizures

       Amy Kao, M.D.
    Division of Neurology
Doernbecher Children’s Hospital
Objectives
• Review the clinical presentation and
  differential diagnosis
• Discuss pathophysiologic implications on
  clinical presentation
• Review etiology
• Apply this information to evaluation and
  treatment
• Discuss prognosis
Clinical Classification
• Focal/Multifocal Clonic
   – Not generalized
   – Migratory
   – Not necessarily focal etiology
• Focal Tonic
  – Not usually generalized
• Generalized Myoclonic
Clinical Classification
• Subtle (“Hypomotor”)
   – Motor activity arrest
   – Apnea
   – Eye deviation
   – Autonomic changes
• Motor automatisms
   – Oral-buccal-lingual movements
   – Swimming
   – Bicycling
 The Definition of a Seizure

“paroxysmal discharge of cerebral
 neurons sufficient to cause clinically
 detectable events that are apparent either
 to the subject or to an observer”
Definition of a Seizure in a Neonate?

• Excitatory activity predominates
• No paroxysmal discharge on EEG?
  – True seizure
     • The cortex is undeveloped
     • Deeper origin
  – “Brainstem release phenomena”
Definition of a Seizure in a Neonate…

• Clinically detectable events?
  – Subtle
  – Truly only electrographic
     • Iatrogenic paralysis
     • High doses AEDs
     • Encephalopathy or subcortical/spinal
       cord damage
If It Isn’t a Seizure, Then What Is It??
 • Possible clues
    – Stimulus-induced
    – Suppressable
    – No associated autonomic changes
      (usually not bradycardia)
Weird Baby Movements
 – Jitteriness
    • Stimulus-sensitive
    • “Tremor”
    • Suppressable
 – Benign neonatal sleep myoclonus
 – Spinal myoclonus
 – Apnea of non-neurologic etiology
    • bradycardia
Causes of Neonatal Seizures
• Within first 24 hours of life
  – Hypoxic ischemic encephalopathy
  – Meningitis/sepsis
  – Subdural/Subarachnoid/Interventricular
    hemorrhage
  – Intrauterine infection
  – Trauma
  – Pyridoxine dependency
  – Drug effect/withdrawal
Causes….

• 24-72 hours
   – Meningitis/sepsis
   – In premature infants: IVH
   – In full-term infants: infarction, venous
     thrombosis
   – Cerebral dysgenesis
Causes….
• 72 hours to 1 week
   – Above causes
   – Inborn errors of metabolism
   – Hypocalcemia
   – Familial neonatal seizures
• 1 week to 4 weeks
   – Above causes
   – HSV
Other Syndromes
• Benign idiopathic neonatal convulsions
  (BINC or Fifth-day fits)
• Benign familial neonatal convulsions
  (BFNC)
• Early myoclonic encephalopathy (EME)
• Early infantile epileptic encephalopathy
  (EIEE)
• Glucose transporter type I
Evaluation of Neonatal Seizures
•   Serum lytes (gluc, Ca, Mg, Na)
•   CSF
•   Head ultrasound
•   EEG (B6?)

• Tox screen
• CT or MRI of brain
• ?metabolic w/u, congenital infection w/u
Treatment of Electroclinical Seizures

• Phenobarbital 20 mg/kg
  – 10 mg/kg boluses until 40-50 microgm/ml
• Phenytoin 20 mg/kg
• Lorazepam 0.1 mg/kg
• Pyridoxine 50-100 mg IV with EEG
Outcome

• 45 % controlled after either phenobarb or
  phosphenytoin
• 60 % controlled with both
• 30% of survivors develop epilepsy
• WORSE: HIE, meningitis, dysplasia
• WORSE: electrographic seizures
• BETTER: hypoCa, BINC, BIFC, stroke
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