Day 3 - Seizure

Definition:

  • Seizures can be classified as generalized or focal, provoked or unprovoked

    • Focal further subdivided into with or without impairment of consciousness

      • The vast majority of adult patients with seizures have focal seizures

        • Most people with generalized epilepsy were diagnosed in adolescence

  • Status epilepticus is a seizure lasting over 15mins, or more than 1 seizure without return to baseline neurological status in between

    • Can be both convulsive or non-convulsive (often identifiable only on EEG)

  • Epilepsy is a seizure disorder, rarely diagnosed in adults - defined as at least 2 unprovoked seizures, 1 unprovoked seizure with possibility or reason to suspect further seizures.

Assessment:

  • Ensure airway is secure, insert oropharyngeal or nasal airway if hypoxic

  • Provide supplemental O2 & obtain IV access if able

  • Monitor duration of seizure & prepare to intervene if >5mins

  • Check CBG during seizure & treat with 1 amp D50W if hypoglycemic

Acute Management of Seizures:

  • Lorazepam 2-4mg IV/SC/SL q3-5min to max dose 0.1mg/kg (generally speaking if 8mg total has been given, further doses unlikely to be effective)

  • Phenytoin 20mg/kg in 250mL NS given at 25-50mg/min

    • Will not abort a seizure, but is used to prevent recurrence

    • Prepare medication as first dose of benzodiazepine being administered, and consider administering concurrently with second dose

    • Monitor for bradycardia

  • If secondary to hyponatremia, administer 3% (hypertonic) saline until seizures aborted

  • If secondary to hypoglycemia, administer 1 amp D50W with routine glucose checks

  • If no response to benzodiazepines & phenytoin, contact ICU for admission & intubation

    • Phenobarbital 5mg/kg IV over 10min q10min to max 10-20mg/kg

      • Monitor closely for decreased LOC requiring intubation

    • Midazolam 0.2-0.5mg/kg/hr (in intubated patients)

    • Propofol 1-2mg/kg bolus then 0.3-3mg/kg/hr (in intubated patients)

Work up: 

  • Neurology Consult

  • Assess for etiology: medication non-adherence, CNS tumour, anoxia/hypoxia, trauma, hypo/hyperglycemia, stroke (uncommon), substance use or withdrawal (alcohol, benzodiazepines), infection (meningitis, encephalitis), medications (penicillins, cephalosporins, fluoroquinolones), electrolyte disturbances (hyponatremia)

  • Labwork:

    • CBC

    • Electrolytes

    • Extended electrolytes

    • Glucose

    • LFTs - usually elevated as the result of the medications 

    • Drug levels if they are on medications (send albumin with phenytoin level)

      • Carbemazepine, Phenytoin with Albumin, Valproic Acid levels

      • Target lowest effective dose - not necessarily therapeutic level

  • EEG 

    • Not used to decide if it was a seizure or not! 

    • Should be used to decide if focal or generalized, and if focal where it came from 

      • Can be useful in someone with known epilepsy to try and see if focality has changed 

    • EEG the vast majority of the time is not capturing the seizure (and if it does it is by chance), it assesses if you are predisposed to seizures 

      • It can take 4-5 EEGs before an abnormality shows up in epileptic patients, 10% never have an abnormality 

  • Imaging

    • CT for first seizure to identify for intracranial lesion as source of seizure

    • MRI required at least once for focal seizures

Discharge

  • Outpatient neurology follow-up

  • First seizures may not require ongoing anti-epileptic therapy

  • MOT form for license suspension until etiology of seizure has been assessed for, and there is evidence of either seizure control on medications or reason to suspect no further seizures will occur

The Intern at Work -