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
- Temporary focal deficit up to 36 hr post-seizure
- Lateral tongue biting - 100% specificity
- Incontinence
Seizure vs. Syncope[5]
- Factors that strongly favor seizure from most specific to least:
- Factors that predict against seizure
- Presyncopal spells
- Prodromal vertigo
- LOC with prolonged standing, sitting
- Diaphoresis, vertigo, nausea, chest pain, feeling of warmth, palpitations, dyspnea before spell
Differential Diagnosis
Seizure
- Epileptic seizure
- First-time seizure
- Seizure with known seizure disorder
- Status epilepticus
- Temporal lobe epilepsy
- Non-compliance with anti-epileptic medications
- Hyponatremia
- INH toxicity
- Non-epileptic seizure
- Meningitis
- Encephalitis
- Brain abscess
- Intracranial hemorrhage
- Alcohol withdrawal
- Benzodiazepine withdrawal
- Barbiturate withdrawal
- Baclofen withdrawal
- Metabolic abnormalities: hyponatremia, hypernatremia, hypocalcemia, hypomagnesemia, hypoglycemia, hyperglycemia, hepatic failure, uremia
- Eclampsia
- Neurocysticercosis
- Posterior reversible encephalopathy syndrome
- Impact seizure (head trauma)
- Acute hydrocephalus
- Arteriovenous malformation
- Seizure with VP shunt
- Toxic ingestion (amphetamines, anticholinergics, cocaine, INH, organophosphates, TCA, salicylates, lithium, phenothiazines, bupropion, camphor, clozapine, cyclosporine, fluoroquinolones, imipenem, lead, lidocaine, metronidazole, synthetic cannabinoids, theophylline, Starfruit)
- Psychogenic nonepileptic seizure (pseudoseizure)
- Intracranial mass
- Syncope
- Hyperventilation syndrome
- Migraine headache
- Movement disorders
- Narcolepsy/cataplexy
- Post-hypoxic myoclonus (Status myoclonicus)
Evaluation
Physical
- Check for:
- Head / C-spine injuries
- Tongue/mouth lacs
- Sides of tongue (true seizure) more often bitten than tip of tongue (psychogenic nonepileptic seizure, formerly "pseudoseizure.")
- Tongue biting has sensitivity of ~25% and approaches 100% specificity in lateral tongue biting[6]
- Posterior shoulder dislocation
- Focal deficit (Todd paralysis vs CVA)
- If new, treat as presumed stroke. Cannot be ruled as Todd's without stroke workup.
- Nuchal rigidity (concern for meningitis)
Work-Up
First-Time Seizure or Change in Baseline Seizures
- Non-contrast head CT in ED (or advanced imaging arranged as outpatient)
- First time seizures in setting of EtOH or EtOH-withdrawal: 6.2% had clinical significant lesion.[7]
- Point-of-care glucose
- Pregnancy test
- CBC & chemistry
- ECG (prolonged QT and torsades can cause shaking after intermittent runs}
- Consider prolactin[8] or lactate to assist in differentiating seizures from psychogenic nonepileptic seizure or volitional seizure activity (lactate may be detectable for up to 1 hour post-seizure)
- Consider: Utox, RPR, HIV, UA, EEG, lumbar puncture, EtOH level, CK
Known Epileptic with NO Change in Baseline Seizures
- Anticonvulsant drug concentration
- Point-of-care glucose
- Trauma workup, if appropriate
- Consider head CT scan if prolonged postictal period or trauma
Management
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]
- Midazolam IM 10 mg (> 40 kg), 5mg (13-40 kg), or 0.2 mg/kg[10]
- 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
- Carbamazepine 8 mg/kg oral suspension, single oral load
- Gabapentin 900 mg/day oral at 300 mg tid for 3 days
- Lamotrigine 6.5 mg/kg single oral load
Other Considerations
- Secondary causes of seizure (e.g. hyponatremia, hypoglycemia, INH toxicity, ecclampsia)
- Nonconvulsive seizures or status epilepticus - get EEG
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
- Anticonvulsants
- Anticonvulsant levels and reloading
- Seizure (peds)
- Febrile seizure
- Status epilepticus
- Alcohol withdrawal seizures
External Links
References
- ↑ Martindale JL, Goldstein JN, Pallin DJ. Emergency department seizure epidemiology. Emerg Med Clin North Am. 2011 Feb;29(1):15-27.
- ↑ 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.
- ↑ Epilepsia 2015; 56:1515-1523.
- ↑ 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.
- ↑ Sheldon R et al. Historical criteria that distinguish syncope from seizures. J Am Coll Cardiol. 2002 Jul 3;40(1):142-8.
- ↑ Benbadis SR et al. Value of tongue biting in the diagnosis of seizures. Arch Intern Med. 1995 Nov 27;155(21):2346-9.
- ↑ Earnest MP, et al. Neurology 1988;38:1561–5.
- ↑ Fisher RS. Serum prolactin in seizure diagnosis: Glass half-full or half-empty?. Neurol Clin Pract. 2016;6(2):100-101.
- ↑ 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.
- ↑ 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
- ↑ 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
- ↑ 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
- ↑ 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
- ↑ PulmCrit- All 2nd line conventional anti-epileptics are equally good… or equally bad?
- ↑ 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
- ↑ 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
- ↑ 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
- ↑ Legriel S, Oddo M, and Brophy GM. What’s new in refractory status epilepticus? Intensive Care Medicine. 2016:1-4.
- ↑ 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.
- ↑ 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.
- ↑ Mirsattari SM et al. Treatment of refractory status epilepticus with inhalational anesthetic agents isoflurane and desflurane. Arch Neurol. 2004 Aug;61(8):1254-9.
- ↑ 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
- ↑ 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.