seizures

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seizures

• Joseph Breuner, MD
• 6/24/03

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Goals

• How to work up first seizure in an adult
• how to order an eeg
• which drugs for which seizures
• status

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How to work up first seizure in an adult

• Objectives
• 1. Was it a seizure? What kind?
• 2. Does the patient have epilepsy

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How to work up first seizure in an adult

• Is it a seizure?
• A seizure is a sudden change in behavior that is
  the consequence of brain dysfunction.
• Learn the following 3 typical and most common
  seizures

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Auras simple partial seizures

• Affect enough of the brain to cause symptoms
• does not impair consciousness--simple
• does not affect the whole brain--partial

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Auras simple partial seizures

• Can precede complex partial seizure
• can evolve to secondarily generalized seizure
• implies epilepsy as opposed to physiologic
  nonepileptic seizures--more on this later

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Auras simple partial seizures

• Long list(50) of typical symptoms,
• symptom depends on which part of the cortex is
  disrupted
• most common jerking of an extremity, epigastric
  discomfort, fear, or an unpleasant smell
• I like foot stomping, spacing out, psychic
  experience, deja and jamais vu

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Complex partial seizure

• Most common type in epileptic adults
• appear to be awake
• consciousness is impaired

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Complex partial seizures

• stare into space/engage in automatisms, such as
  grimacing, gesturing, chewing, lip smacking
• last 3 minutes or less
• post-ictal somnolence, confusion, headache for
  up to several hours

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Generalized tonic-clonic seizure

• No aura
• tonic phase x 10-20 seconds
• sudden LOC, loss of posture, arms flex, eyes
  deviate upward
• extension of back, neck, arms, legs
• involuntary crying out
• ends with tremors which merge c clonic phase

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Generalized tonic-clonic seizure

• Clonic phase x 90 seconds
• brief, violent, generalized flexor contractions
  alternating with progressively longer muscle
  relaxation
• cyanosis
• cheek or tongue biting, salivation
• loss of bowel, bladder control

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Generalized tonic-clonic seizure

• Post ictal phase x minutes to hours
• headache
• mild confusion
• sore muscles
• may sleep and feel refreshed

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How to work up first seizure in an adult

• Is it a seizure?
• 4 conditions can mimic a seizure and are worth
  knowing about
• REM behavior disorder
• Transient ischemic attack
• Transient global amnesia
• Migraine

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How to work up first seizure in an adult

• A good time to point out that
• history rules!!!
• Physical exam, lab and even EEG are way less
  important than history

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How to work up first seizure in an adult

• REM behavior disorder REM behavior disorder is
  a parasomnia that consists of sudden arousals
  from REM sleep immediately followed by
  complicated, often aggressive, behaviors for
  which the patient is amnestic. Diagnosis is
  clarified by overnight sleep testing

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How to work up first seizure in an adult

• Transient ischemic attack (TIAs) may last seconds
  to minutes.
• characterized by "negative" symptoms and signs
  (such as weakness or visual loss)
• postictal state may include lateralizing
  "negative" symptoms such as weakness

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How to work up first seizure in an adult

• Transient global amnesia is a condition of
  vascular etiology,
• occurs after the age of 50.
• deficit of short-term memory that begins abruptly
  and persists for minutes to hours, without other
  cognitive or motor impairment. Episodes are
  usually not recurrent.

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How to work up first seizure in an adult

• Migraine Migraine auras such as visual
  illusions and basilar migraine symptoms,
  including altered consciousness, can mimic
  complex partial seizures
• the headache that follows complex partial and
  generalized tonic-clonic seizures is migrainous
  in quality and duration.

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How to work up first seizure in an adult

• Is it a seizure?
• If its not REM behavior disorder
• Transient ischemic attack
• Transient global amnesia, or
• Migraine
• its probably a seizure

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Is it epilepsy?

• Question 2 is it epilepsy?
• Differentiate physiological and psychogenic
  seizures from epileptic seizures

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Is it epilepsy?

• Why do I care about this?
• Epilepsy treated with anticonvulsants
• Physiologic/psychogenic seizures you treat the
  disorder
• This evaluation will determine the likelihood
  that a patient will have additional seizures and
  assist in the decision whether to begin
  anticonvulsant therapy

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Is it epilepsy?

• Is it epilepsy?
• In epileptic seizures the EEG is abnormal

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Is it epilepsy?

• Physiologic seizures are caused by
• hyper- and hypothyroidism
• Hypoglycemia
• Nonketotic hyperglycemia -focal motor seizures

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Is it epilepsy?

• Physiologic seizures caused by
• Precipitous falls in serum sodium-high mortality
• Hypocalcemia--neonates
• Renal failure and uremia

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Is it epilepsy?

• Physiologic seizures
• Acute intermittent porphyria--also includes
  abdominal pain and behavior changes
• Cerebral anoxia--including brief syncope, though
  these patiens wont be post ictal
• alcohol withdrawal3-72 hrs post last drink

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Is it epilepsy?

• Medication history tricyclic antidepressants can
  lower seizure threshold

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Is it epilepsy?

• PMH--head injury
• stroke
• alzheimers disease
• history intracranial infection
• alcohol/drug abuse

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Is it epilepsy?

• Family history
• if positive, highly suggestive of epilepsy
• especially for absence seizures and myoclonic
  seizures

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Is it epilepsy?

• Physical exam/neuro exam
• rarely helpful except in setting of acute
  infection or hemorrhage
• look for lateralizing abnormalities

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Is it epilepsy?

• Lab eval epilepsy vs physiologic
• glucose
• calcium
• magnesium
• BUN/cr
• tox screen
• TSH

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Is it epilepsy?

• Lumbar puncture--only useful if infection or
  malignant metastasis to the meninges

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Is it epilepsy?

• Neuroimaging
• unless obvious physiologic seizure, should obtain
  MRI.
• MRI better than CT for infarcts and tumors
• the older the patient, the more likely you will
  find a structural cause

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How to order an eeg

• Looking for seizure focus
• substantiates epilepsy if positive
• can indicate generalized vs partial seizure
  disorder

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How to order an eeg

• Sleep deprivation
• hyperventilation
• intermittent photic stimulation
• all increase the yield
• usually okay to begin with awake eeg, sleep
  deprive if high index of suspicion

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How to order an eeg

• Study of 157 adult pts with untreated first
  idiopathic seizure
• obtained single awake eeg, if normal, also
  obtained eeg p sleep deprivation

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How to order an eeg

• Risk of 2nd seizure in 2 years (CI)
• epileptic discharges 83 (69-97)
• nonepileptic abnormalities 43 (29-53)
• normal 12 (3-21)

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Which drugs for which seizures?

• In general, recurrence risk at one year after
  first seizure is 15-30
• three year recurrence risk is 30-78
• treatment roughly halves recurrence risk

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Which drugs for which seizures?

• Risk factors for recurrence are
• head injury
• A lesion on MRI
• Focal deficits on neuro exam A record of
  cognitive impairment A partial seizure as the
  first seizure An abnormal EEG (particularly
  epileptiform abnormalities)

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Which drugs for which seizures

• A record of cognitive impairment
• A partial seizure as the first seizure
• An abnormal EEG (particularly epileptiform
  abnormalities)

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Which drugs for which seizures

• Absent risk factors, it makes sense to wait for
  second seizure prior to initiating treatment

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Which drugs for which seizures?

• Cochrane reviews looked at 4 outcomes
• time to withdrawal of treatment
• 6 month remission rate
• 12 month remission rate
• time to first seizure p randomization

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Which drugs for which seizures?

• Carbamazepine better than phenobarb only in
  longer time to treatment withdrawal due to side
  effects--treatment efficacy the same

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Which drugs for which seizures?

• Carbamazepine equivalent to valproate for both
  partial and generalized seizures
• trend for carbamazepine to improved 12 month
  remission for partial seizures

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Which drugs for which seizures?

• Phenytoin better than phenobarb solely due to
  side effects--treatment efficacy the same

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Which drugs for which seizures?

• Carbamazepine equivalent to phenytoin

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Which drugs for which seizures?

• Phenytoin equivalent to valproate

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Which drugs for which seizures?

• Summary of cochrane data
• carbamazepine
• phenytoin
• valproate are all equivalent in efficacy and
  tolerability
• phenobarb also efficacious but more side effects

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status

• Dont give meds unless youre in a setting where
  you can control airway
• ativan 2mg or valium 5mg IVP q 2-4 minutes PRN
• load fosphenytoin 20 mg/kg iv
• to icu

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References

• Up to date
• evaluation of the first seizure, 12/02/01
• treatment of chronic epilepsy
• van donselaar, CA, value of the eeg in adult
  patients, arch neurol 1992
• cochrane database
• swedish admit orders for status epilepticus

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Take home points

• Workup of first seizure--was it a seizure, what
  kind was it. Aura important
• physiologic seizures vs. epilepsy
• anticonvulsant therapy reduces recurrence risk by
  1/2