Seizures and epilepsy are common, serious neurologic diseases in children and adolescents.^1,2 Convulsions can be a manifestation of epilepsy or occur secondary to a complication of a systemic or central nervous system disorder. The emergency physician is usually the first provider to evaluate and stabilize children with suspected seizures. Here, we will review recent literature and share our personal experience in the approach to a seizing child in the emergency department.

Epilepsy is defined as the predisposition to generate seizures.^3,4 While generalized or focal shaking in a child readily raises a concern for seizure in caregivers and doctors alike, subtle manifestations, such as brief episodes of lip smacking in temporal lobe epilepsy or head bobbing in infantile spasms, can be challenging to correctly detect as signs of a serious neurologic disorder.

As with any other patient presenting to the emergency department, assessment of seizing children starts with determining stability and urgently addressing the ABCs. Careful attention should be given to the possibility of continuous seizure activity even if no apparent convulsions are seen. It’s helpful to consider the possibility that seizures were provoked so that their causes can be diagnosed and addressed.³ Table 1 enumerates causes of provoked seizures in patients without epilepsy.

(click for larger image) Table 1: Select Causes of Provoked Seizures⁸

Published guidelines on imaging in children with new-onset seizures note that in only approximately 2 to 4 percent of cases, the results altered immediate medical management.⁵ While MRI is the most accurate diagnostic modality in pediatric patients, for unstable patients in whom space-occupying lesions need to be excluded, a noncontrast CT scan of brain is the modality of choice as it is rapid, is readily available, and generally does not require sedation.^5,6 It is unusual to find an acute abnormality on imaging of a normally developed child (not an infant) with a completely normal neurological examination after a brief, nonlocalizing seizure.⁵ In these patients, imaging can be done on an outpatient basis as necessary. The same can be said for laboratory testing.

It is important to note that there are few studies prospectively evaluating timing of imaging in children with new-onset epilepsy. Some high- and low-risk characteristics are based on electroencephalogram (EEG) results. Most guidelines also exclude neonatal seizures.⁵ A seizure in a neonate almost always requires expeditious imaging and an EEG.6 An otherwise healthy and developmentally normal child older than 24 months after a brief first-time generalized seizure who quickly returns to normal can be discharged without medications with follow-up by pediatric neurology.^3,4,7,8 All of these patients will ultimately need an EEG, and most will require an MRI of the head.^5,6

As in adults, most children suffering a first unprovoked seizure do not have another one, especially if their EEG is normal. The risk is higher in children with autistic spectrum disorders and if the seizure happens during sleep.⁷ If it occurs, recurrent seizure is most common in the first six months after the first one.⁷ While sudden unexpected death in epilepsy (SUDEP) is a known and feared entity that is currently impossible to predict in any given patient, most excess mortality in children with epilepsy is not caused by a seizure itself.⁹ Great care should be taken when evaluating infants. Sepsis, meningitis, or disseminated herpes infection can manifest initially with a seizure with or without an abnormal temperature. Appropriate discharge instructions related to trauma and burn prevention, avoiding driving and taking care of babies, and not swimming or lying in a bath without close supervision are of paramount importance.

Febrile Seizures

Febrile seizures are most commonly defined as those occurring in children of defined age (6 to 60 months, per the American Academy of Pediatrics 2008 guideline) without prior afebrile seizures or neurological abnormalities and occurring in association with acute febrile illness when no other precipitating condition is identified.10 Complex febrile seizures have focal onset, have lateralizing signs, last longer than 15 minutes, are associated with prolonged postictal deficits, or occur more than once in a given acute febrile illness. These represent approximately 40 percent of all febrile seizure presentations.¹⁰ Febrile seizures that are not complex are defined as simple. Children typically are highly febrile if presenting soon after the seizure; low-grade fever is unusual with febrile seizures unless antipyretics were already given. Seizures lasting more than five minutes currently meet criteria for status epilepticus (SE).¹¹

Management of patients with simple febrile seizures in the emergency department is similar to the management of children presenting with fever without a seizure and focuses on exclusion of serious illness such as meningitis or sepsis. The 2011 guidelines from the American Academy of Pediatrics do not recommend routine imaging, EEG, lumbar puncture, blood work, or urinalysis solely because of a simple or complex febrile seizure. Unimmunized young children (less than one year old), those on antibiotics, or those with sick appearance warrant a more extensive workup. Children seizing in the emergency department can be given benzodiazepines with intramuscular (IM), IV, intranasal, and rectal routes described.^3,10,12 The decision to prescribe rectal diazepam for use in subsequent febrile seizure episodes is controversial and must be balanced with potential of apnea after its administration.¹⁰ As the seizure typically occurs when fever spikes, antipyretics do not help to prevent first or subsequent febrile seizures.

SE is defined as seizure activity lasting more than five minutes or recurrent seizures without recovery in between.^11,13 It is the most common neurological emergency in childhood.¹³ Prolonged seizure activity can permanently damage neurons; the longer a seizure lasts, the less likely it is to stop spontaneously and the less likely it is to respond to standard antiepileptic drugs (AEDs).³ SE appears to increase expression of drug efflux proteins in the brain, thus decreasing AED levels there.¹³ As it is impossible to predict how long a given seizure will last, it’s best to administer appropriate medications without delay by the fastest reliable route available and escalate therapy as necessary. Intramuscular midazolam administration has been shown to be safe and effective for prehospital SE.¹² IV access can be challenging in seizing children, especially if the veins were extensively used in the past. An intraosseous line can be lifesaving in this situation. Early cardiorespiratory monitoring and supplemental oxygen are recommended for all patients.

For suggested diagnostic workup of SE, see Table 2. For medication sequence in treating SE, refer to Table 3. Both seizure activity and medications used to terminate it can cause respiratory failure. Bag-valve-mask ventilation can sometimes stave off the need for endotracheal intubation unless emergent imaging or other diagnostic procedures are immediately needed. In case of ongoing seizure activity or altered mental status, EEG monitoring is recommended early.^11,13

(click for larger image) Table 2: Important Diagnostic Tests for Patients in Status Epilepticus^11,13

Nonconvulsive SE (NCSE)

Prolonged brain seizure activity on EEG in a patient with altered mental status but without convulsions defines NCSE. It can present separately as an acute confusional state or develop following an observed seizure.¹¹ A wide variety of symptoms have been described, ranging from aphasia to severe agitation or coma.¹¹ It appears to have a similar incidence in children and adults and is not rare.^14,15 In settings where immediate EEG is not available, its recognition can be quite challenging. In our experience, in unclear cases, cautious administration of a weight-appropriate benzodiazepine dose can, at times, result in dramatic improvement in mental status aiding in diagnosis. Similarly to patients with convulsive SE, these patients need emergent workup focusing on diagnosing life-threatening etiologies, continuous EEG monitoring, and expeditious AED administration. As is the case with convulsive SE, the prognosis mostly depends on etiology and the degree of neurological impairment.¹³

(click for larger image) Table 3: Suggested Intervention Sequence in Treatment of Pediatric Status Epilepticus^{3,11–14,18,19}

Psychogenic Nonepileptic Seizure (PNES) and Other Seizure Mimics

PNES is defined as repeated and frequently intractable seizure activity in the absence of epileptogenic changes on concurrently recorded EEG.16 Video EEG is necessary to firmly establish the diagnosis, and psychiatric comorbidities are common in both PNES and epilepsy.16 As many as a quarter of children thought to be suffering from seizures are ultimately found to have PNES.¹⁷ Misdiagnosis leads to inappropriate use of antiepileptic drugs with corresponding side effects up to and including the need for mechanical ventilation. Appropriate referral and treatment achieved an 80 percent remission rate in one study.¹⁷

Special Populations

(click for larger image) Table 4: Select Antiepileptic Drugs (AEDs)^2,3,8,20
While numerous new AEDs are now available, it’s unknown if they are any more effective and safer than the old ones.²¹ While AEDs can lower the chance of a seizure occurrence, they do not treat epilepsy or prevent the development of it.
NOTE: AEDs with US Food and Drug Administration boxed warnings are carbamazepine, felbamate, lamotrigine, perampanel, and valproic acid

There are new imaging techniques such as diffusion tensor images and MRI fused with specialized PET imaging that have improved detection of epileptogenic foci amenable to surgery in children with intractable epilepsy.⁶

Conclusion

Seizures are a common complaint in children presenting to the emergency department. The initial focus should be on stabilization of vital functions as well as rapid diagnostic workup to exclude treatable secondary causes. Febrile seizures are a unique pediatric pathology where management now mostly focuses on the concurrent, acute febrile illness. Convulsive and nonconvulsive SE are true neurological emergencies and should be stabilized as soon as possible. PNES is common, and video EEG monitoring is required to firmly establish the diagnosis.

Dr. Garber is assistant professor of emergency medicine at Case Western Reserve University in Cleveland.

Dr. Glauser is professor of emergency medicine at Case Western Reserve University.

References

1. Dörks M, Langner I, Timmer A, et al. Treatment of paediatric epilepsy in Germany: antiepileptic drug utilisation in children and adolescents with a focus on new antiepileptic drugs. Epilepsy Res. 2013;103(1):45-53.
2. O’Connell BK, Gloss D, Devinsky O. Cannabinoids in treatment-resistant epilepsy: a review. Epilepsy Behav. 2017;70(Pt B):341-348.
3. Abend NS, Huh JW, Helfaer MA, et al. Anticonvulsant medications in the pediatric emergency room and intensive care unit. Pediatr Emerg Care. 2008;24(10):705-718.
4. Fisher RS, Acevedo C, Arzimanoglou A, et al. ILAE official report: a practical clinical definition of epilepsy. Epilepsia. 2014;55(4):475-482.
5. Gaillard WD, Chiron C, Cross JH, et al. Guidelines for imaging infants and children with recent-onset epilepsy. Epilepsia. 2009;50(9):2147-2153.
6. Rastogi S, Lee C, Salamon N. Neuroimaging in pediatric epilepsy: a multimodality approach. Radiographics. 2008;28(4):1079-1095.
7. Maia C, Moreira AR, Lopes T, et al. Risk of recurrence after a first unprovoked seizure in children. J Pediatr (Rio J). 2017;93(3):281-286.
8. Shorvon SD. The etiologic classification of epilepsy. Epilepsia 2011;52(6):1052-1057.
9. Berg AT, Nickels K, Wirrell EC, et al. Mortality risks in new-onset childhood epilepsy. Pediatrics. 2013;132(1):124-131.
10. Kimia AA, Bachur RG, Torres A, et al. Febrile seizures: emergency medicine perspective. Curr Opin Pediatr. 2015;27(3):292-297.
11. Brophy GM, Bell R, Claassen J, et al. Guidelines for the evaluation and management of status epilepticus. Neurocrit Care. 2012;17(1):3-23.
12. Silbergleit R, Durkalski V, Lowenstein D, et al. Intramuscular versus intravenous therapy for prehospital status epilepticus. N Engl J Med. 2012;366(7):591-600.
13. Mastrangelo M, Celato A. Diagnostic work-up and therapeutic options in management of pediatric status epilepticus. World J Pediatr. 2012;8(2):109-115.
14. Greiner HM, Holland K, Leach JL, et al. Nonconvulsive status epilepticus: the encephalopathic pediatric patient. Pediatrics. 2012;129(3):e748-755.
15. Glass HC, Kan J, Bonifacio SL, et al. Neonatal seizures: treatment practices among term and preterm infants. Pediatr Neurol. 2012;46(2):111-115.
16. Scévola L, Teitelbaum J, Oddo S, et al. Psychiatric disorders in patients with psychogenic nonepileptic seizures and drug-resistant epilepsy: a study of an Argentine population. Epilepsy Behav. 2013;29(1):155-160.
17. Sawchuk T, Buchhalter J. Psychogenic nonepileptic seizures in children—psychological presentation, treatment, and short-term outcomes. Epilepsy Behav. 2015;52(Pt A):49-56.
18. Kossoff EH, Nabbout R. Use of dietary therapy for status epilepticus. J Child Neurol. 2013;28(8):109-1051.
19. Rosati A, L’Erario M, Ilvento L, et al. Efficacy and safety of ketamine in refractory status epilepticus in children. Neurology. 2012;79(24):2355-2358.
20. Tzadok M, Uliel-Siboni S, Linder I, et al. CBD-enriched medical cannabis for intractable pediatric epilepsy: the current Israeli experience. Seizure. 2016;35:41-44.
21. Rosati A, De Masi S, Guerrini R. Antiepileptic drug treatment in children with epilepsy. CNS Drugs. 2015;29(10):847-863.