Seizure

This page covers seizures in general; refer to status epilepticus for persistently seizing patients and seizure (peds) for pediatric patients.

Background

  • Caused by a pathologic pattern of brain cortex activity (time-limited paroxysmal events from abnormal rhythmic neuronal discharges) → involuntary movement or change in level of consciousness[1]
    • 11% of people will have at least one seizure in their lifetime
    • 3% will have epilepsy (at least 2 unprovoked seizures)
  • In pregnancy >20 WGA or <4wks postpartum, need to consider eclampsia
    • Most seizures in pregnancy are not first-time seizures, but rather are due to medication noncompliance or pharmacokinetic drug changes as result of pregnancy
  • The most common etiology of seizure is noncompliance with medication

Seizure Types

Classification is based on the international classification from 1981[2]; More recent terms suggested by the ILAE (International League Against Epilepsy) task Force.[3]

Focal seizures

(Older term: partial seizures)

  • Without impairment in consciousness– (AKA Simple partial seizures)
    • With motor signs (ex. facial twiching or rhythmic ipsilateral extremity movements)
    • With sensory symptoms (ex. tingling or pereiving a certain smell)
    • With autonomic symptoms or signs (ex. tachycardia or diaphoresis)
    • With psychic symptoms (including aura, ex. sense of déjà-vu)
  • With impairment in consciousness - (AKA Complex Partial Seizures--Older terms: temporal lobe or psychomotor seizures)
    • Simple partial onset, followed by impairment of consciousness
    • With impairment of consciousness at onset
    • These seizures may be accompanied by automatism (such as lip smacking and chewing, hand wringing, patting and rubbing)
  • Focal seizures evolving to secondarily generalized seizures
    • Simple partial seizures evolving to generalized seizures
    • Complex partial seizures evolving to generalized seizures
    • Simple partial seizures evolving to complex partial seizures evolving to generalized seizures

Generalized seizures

  • Absence seizures (Older term: petit mal; brief dissociative states without postural changes)
    • Typical absence seizures
    • Atypical absence seizures (last longer and often include more motor involvement)
  • Myoclonic seizure (violent muscle contractions)
  • Clonic seizures (rhythmic jerking)
  • Tonic seizures (stiffening)
  • Tonic–clonic seizures (Older term: grand mal)
  • Atonic seizures (loss of muscle tone -> drop attacks)

SUDEP[4]

  • Sudden Unexpected Death in Epilepsy
  • Generalized tonic-clonic seizure is the major risk factor for SUDEP, and seizure freedom is strongly associated with decreased risk
    • Annual incidence of SUDEP in children is 1 in 4500
    • Incidence in adults is 1 in 1000

Clinical Features

  • Abrupt onset, may be unprovoked
  • Brief duration (typically <2min)
  • AMS
  • Jerking of limbs
  • Postictal drowsiness/confusion (typically lasting <30 minutes)
  • Todd paralysis
  • Lateral tongue biting - 100% specificity
  • Incontinence

Seizure vs. Syncope[5]

  • Factors that strongly favor seizure from most specific to least:
    • Waking with cut tongue
    • Abnormal behavior noted by bystanders
    • LOC with emotional stress
    • Postictal confusion
    • Head turning to one side during LOC
    • Prodromal deja vu or jamais vu
  • Factors that predict against seizure

Differential Diagnosis

Differential diagnosis of seizures

Seizure

Evaluation

Physical

Work-Up

First-Time Seizure or Change in Baseline Seizures

Known Epileptic with NO Change in Baseline Seizures

Management

Management of seizures

Seizure Precautions

  • Protect patient from injury
    • If possible, place patient in left lateral position to reduce risk of aspiration
    • Do not place bite block!
  • Jaw thrust, a NPA and oxygen may be required
  • An IV line should be placed

Medications

  • Benzodiazepine (Initial treatment of choice)[9]
    • Midazolam IM 10 mg (> 40 kg), 5mg (13-40 kg), or 0.2 mg/kg[10]
      • May also be given IN at 0.2 mg/kg, max 10 mg
      • OR buccal at 0.3 mg/kg, max 10 mg
    • Lorazepam IV 4 mg or 0.1 mg/kg; may repeat one dose[11]
    • Diazepam IV 0.15-0.2 mg/kg (up to 10 mg); may repeat one dose or PR 0.2-0.5 mg/kg (up to 20 mg) once [12]
  • Secondary medications
    • ESETT trial[13] compared second line antiseizure medications and they all are equally efficacious. Therefore may be best to use the one with least side effects [14] which is Levetiracetam
    • Levetiracetam IV 60 mg/kg, max 4500 mg/dose, or 1500 mg oral load (preferred in pregnancy)[15]
    • Phenytoin IV 18 mg/kg at ≤ 50 mg/min (avoid in pregnancy)[16]
    • Fosphenytoin IV 20-30 mg/kg at 150 mg/min (may also be given IM)
      • Contraindicated in pts w/ 2nd or 3rd degree AV block
      • Avoid phenytoin or fosphenytoin in suspected toxicology case due to sodium channel blockade
    • Valproic acid IV 20-40 mg/kg at 5 mg/kg/min, max 3000 mg (avoid in pregnancy)[17]
  • Refractory medications
    • Propofol 2-5mg/kg, then infusion of 2-10mg/kg/hr OR
    • Midazolam 0.2mg/kg, then infusion of 0.05-2mg/kg/hr OR
    • Ketamine loading dose 0.5 to 3 mg/kg, followed by infusion of 0.3 to 4 mg/kg/hr[18]
    • Lacosamide IV 400 mg IV loading dose over 15 min, then maintenance dose of 200 mg q12hrs PO/IV[19]
    • Phenobarbital IV 15-20 mg/kg at 50-75 mg/min[20]
      • Then continuous infusion at 0.5-4.0 mg/kg/hr
      • Dose adjusted to suppression-burst pattern on continuous EEG
    • Consider consulting anesthesia for inhaled anesthetics (potent anticonvulsants)[21]
  • Others

Other Considerations

Disposition

First-Time Seizure

  • Those with single generalized seizure and otherwise normal history and physical can be discharged home with close follow-up[22]
    • Observation is not unreasonable for those that look ill or have a complicating history/physical (comorbidities, age > 60y, cancer, immunocompromise, cardiovascular disease)
    • 24-hr recurrence of seizures in this group is about 9% when alcohol-related events are excluded[23]
  • Instructions not to drive, swim, or participate in other potentially dangerous activities is important
  • Outpatient neurology follow-up

See Also

External Links

References

  1. Martindale JL, Goldstein JN, Pallin DJ. Emergency department seizure epidemiology. Emerg Med Clin North Am. 2011 Feb;29(1):15-27.
  2. Proposal for revised clinical and electroencephalographic classification of epileptic seizures. From the Commission on Classification and Terminology of the International League Against Epilepsy. Epilepsia 1981; 22:489.
  3. Epilepsia 2015; 56:1515-1523.
  4. Harden C et al. American Academy of Neurology and the American Epilepsy Society. Practice guideline summary: Sudden unexpected death in epilepsy incidence rates and risk factors. Neurology April 25, 2017 vol. 88 no. 17 1674-1680.
  5. Sheldon R et al. Historical criteria that distinguish syncope from seizures. J Am Coll Cardiol. 2002 Jul 3;40(1):142-8.
  6. Benbadis SR et al. Value of tongue biting in the diagnosis of seizures. Arch Intern Med. 1995 Nov 27;155(21):2346-9.
  7. Earnest MP, et al. Neurology 1988;38:1561–5.
  8. Fisher RS. Serum prolactin in seizure diagnosis: Glass half-full or half-empty?. Neurol Clin Pract. 2016;6(2):100-101.
  9. Glauser T, et al. Evidence-based guideline: treatment of convulsive status epilepticus in children and adults: report of the guideline committee of the American Epilepsy Society. Epilepsy Curr. 2016; 16(1):48-61.
  10. McMullan J, Sasson C, Pancioli A, Silbergleit R: Midazolam versus diazepam for the treatment of status epilepticus in children and young adults: A meta-analysis. Acad Emerg Med 2010; 17:575-582
  11. Glauser T, Shinnar S, Gloss D, et al. Evidence-Based Guideline: Treatment of Convulsive Status Epilepticus in Children and Adults: Report of the Guideline Committee of the American Epilepsy Society. Epilepsy Curr. 2016;16(1):48-61. doi:10.5698/1535-7597-16.1.48
  12. Glauser T, Shinnar S, Gloss D, et al. Evidence-Based Guideline: Treatment of Convulsive Status Epilepticus in Children and Adults: Report of the Guideline Committee of the American Epilepsy Society. Epilepsy Curr. 2016;16(1):48-61. doi:10.5698/1535-7597-16.1.48
  13. Kapur J, Elm J, Chamberlain J, et al. Randomized Trial of Three Anticonvulsant Medications for Status Epilepticus. N Engl J Med. 2019;381(22):2103-2113. doi:10.1056/NEJMoa1905795
  14. PulmCrit- All 2nd line conventional anti-epileptics are equally good… or equally bad?
  15. Macri E, Greene-Chandos D. Neurological Emergencies During Pregnancy. Neurol Clin. 2021 May;39(2):649-670. doi: 10.1016/j.ncl.2021.02.008. PMID: 33896537
  16. Macri E, Greene-Chandos D. Neurological Emergencies During Pregnancy. Neurol Clin. 2021 May;39(2):649-670. doi: 10.1016/j.ncl.2021.02.008. PMID: 33896537
  17. Macri E, Greene-Chandos D. Neurological Emergencies During Pregnancy. Neurol Clin. 2021 May;39(2):649-670. doi: 10.1016/j.ncl.2021.02.008. PMID: 33896537
  18. Legriel S, Oddo M, and Brophy GM. What’s new in refractory status epilepticus? Intensive Care Medicine. 2016:1-4.
  19. Legros B et al. Intravenous lacosamide in refractory seizure clusters and status epilepticus: comparison of 200 and 400 mg loading doses. Neurocrit Care. 2014 Jun;20(3):484-8.
  20. Pugin D et al. Is pentobarbital safe and efficacious in the treatment of super-refractory status epilepticus: a cohort study. Critical Care 2014. DOI: 10.1186/cc13883.
  21. Mirsattari SM et al. Treatment of refractory status epilepticus with inhalational anesthetic agents isoflurane and desflurane. Arch Neurol. 2004 Aug;61(8):1254-9.
  22. Huff JS, Melnick ER, Tomaszewski CA, et al. Clinical policy: critical issues in the evaluation and management of adult patients presenting to the emergency department with seizures [published correction appears in Ann Emerg Med. 2017 Nov;70(5):758]. Ann Emerg Med. 2014;63(4):437-47.e15. doi:10.1016/j.annemergmed.2014.01.018
  23. Krumholz A, Wiebe S, Gronseth G, et al. Practice Parameter: evaluating an apparent unprovoked first seizure in adults (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology and the American Epilepsy Society. Neurology. 2007; 69(21):1996-2007.