Seizures are the most common neurologic disorder in children in the United States.¹ A seizure is defined as abnormal, excessive, transient paroxysmal electrical discharge of neurons within the brain. Epilepsy is defined as two or more unprovoked (absence of fever, acute trauma, etc.) seizures. Although 1 in 10 individuals will experience a seizure in their lifetime, seizures are still poorly understood with regard to etiology and optimal treatment. As such, seizures can be a vexing and anxiety-provoking event for emergency medicine physicians, staff, and the families of affected children.

The etiology and pathophysiology of seizures is poorly understood, and manifestations of this process are quite variable. These manifestations may include changes in behavior, consciousness, sensation, motor activity, or autonomic function. Some seizures are very subtle, described as daydreaming, to the opposite extreme of generalized convulsing of the body with loss of consciousness. An international classification of epilepsies and seizures disorders was developed in 1989 and continues to serve to classify seizures (Table 53-1).¹ A revised terminology for seizures and epilepsies was released by the International League Against Epilepsy (ILAE) Commission in 2009.² Neither classification is particularly useful or prescriptive for guiding acute management in the emergency department (ED), but can be useful in communicating with neurologists when determining the need for ongoing anticonvulsive therapies.

There are a few seizure types that are unique to pediatrics. These include benign Rolandic seizures, juvenile myoclonic epilepsy, and infantile spasms. These can often be diagnosed based on their unique presentations, and may obviate the need for some diagnostic evaluations.

Infantile spasms (West syndrome) typically present between 4 and 18 months of age, with males more commonly affected. The vast majority have mental retardation, and the mortality rate is quite high. These seizures are characterized by clusters of sudden jerking contractions of the head, trunk, and extremities. The electroencephalogram (EEG) shows a characteristic hypsarrhythmia pattern. Optimal treatment is high-dose Adrenocorticotropic hormone (ACTH).³

Benign Rolandic epilepsy occurs in children aged 3 to 13 years and is most prevalent in the 5- to 10-year age range. It is inherited as an autosomal dominant trait. These patients have brief seizures as they fall asleep. Features of a typical attack involve twitching, numbness, or tingling of the child’s face, tongue, and shoulders which often interferes with speech and may cause drooling. These seizures last no more than 2 minutes and the child may remain fully conscious, or sometimes the child also may have tonic–clonic seizures, usually during sleep. The seizures are usually infrequent, but they may occur in widely-spaced clusters. Avoiding sleep deprivation may significantly reduce the frequency of these seizures. These seizures resolve at the time of puberty and unless they are frequent, treatment is not required. In a few patients, cognitive/academic dysfunction may occur and further care may be warranted.⁴ An EEG in concert with the history is generally diagnostic. Patients with typical clinical and EEG features do not need a CT or MRI.

Juvenile myoclonic epilepsy is an inherited autosomal dominant trait and presents in early adolescence, typically 12 to 18 years of age. Generally, patients are reported as having jerking episodes on awakening. These can be generalized as well. Typically, these are provoked by lack of sleep, stress, hormonal changes, or other factors. EEG is helpful in the diagnosis, and these cases almost always require treatment because of their recurrent nature. Valproate is the drug of choice, with levetiracetam and zonisamide as alternates.⁵

MANAGEMENT OF THE PATIENT WITH AN ACUTE SEIZURE

Most patients who present for evaluation of an acute seizure are no longer seizing on arrival in the ED. Initial evaluation consists of a brief and directed history and physical examination. Based on this, a determination as to whether the patient has had a seizure is made. If the seizure is ongoing, our primary objectives are supporting airway, breathing, circulation (ABCs), and cessation of any seizure activity.

There are several paroxysmal events that may be challenging to differentiate from a true seizure. Seizure-like symptoms can be seen with breath-holding spells, pseudo-seizures/psychogenic, syncope, gastroesophageal reflux, tics, and sleep-related movements. Differentiating these is largely contingent on a thorough and detailed history. Blurred vision or seeing black spots, dizziness/lightheadedness, and pallor usually precede syncopal episodes. Gastroesophageal reflux usually results in arched back positioning with crying, no loss of consciousness, and is temporally related to feeding. Cyanotic breath-holding spells usually occur after an intense crying episode, followed by holding one’s breath, and then loss of consciousness and the child becomes limp. The child often turns bluish and may sweat. With a pallid breath-holding spell, the infant often sustains minor head trauma, loses consciousness, stops breathing, and becomes pale and limp. They may develop a generalized increase in muscle tone with incontinence and have a postictal period. During a pseudo-seizure, the patient keeps their eyes tightly closed and resists eye opening, avoids painful stimuli, and lacks a postictal phase. Daydreamers can immediately be “brought back to earth” with verbal or physical stimuli. The absence of motor movements may also help to distinguish it from absence seizures.

HISTORY

The history should include any previous history of neurologic abnormalities, developmental delays, mental illness, or seizures, including any known triggers. The events (immediately) (temporally related) prior to the onset of seizures may also elicit clues. For example, the onset of a febrile illness, recent trauma, or the child was being babysat by grandma who is known to take a variety of prescription medications. Prodromal symptoms should be noted such as an aura or dizziness that may indicate migraines or a syncopal event. An accurate description of the seizure including motor activity (focality), level of consciousness, incontinence, length of seizure, and a postictal state are useful. In patients with a history of seizure, any variance from a “typical seizure” should be noted. It is important to point out that some patients will present simply with altered mental status and may be in “nonconvulsive status.” In addition, some motor movements may be very subtle, and in a moment of crisis, go unrecognized by caretakers. Practitioners on their examination often miss these subtleties as well.

PHYSICAL EXAMINATION

The brief directed initial examination should ensure that the ABCs are addressed and a full set of vital signs obtained. Often, following an acute seizure, patients will have a period of respiratory depression that can be managed with supplemental oxygen. Occasionally, respirations may need to be supported with bag-valve-mask ventilation. The likelihood of this transient respiratory depression increases if family members or prehospital personnel administered an anticonvulsant medication. Securing the airway needs to be determined on a case-by-case basis. Subsequently, a neurologic survey is done where a determination of ongoing seizure activity versus postictal state should be made. The family, particularly with recurrent seizures, can be instrumental in helping the practitioner make this distinction. A more systematic head-to-toe examination should ensue looking for signs of trauma, toxidromes, CNS infection (meningismus), dysmorphic features, or a focal neurologic deficit. New focal deficits would be concerning for an acute intracranial process that should prompt emergent neuroimaging. Certain cutaneous manifestations may prompt one to consider neurofibromatosis, tuberous sclerosis, or other neurocutaneous disorder. If on presentation the patient has not returned to his/her baseline, it is imperative to ensure that serial reevaluations are performed. Patients who have not returned to their baseline during an observation period may benefit from further evaluation or inpatient observation. The caregiver’s input may reveal that “Johnny typically sleeps for 8 hours postseizure” and they manage this at home. In patients without previous seizures no such assumptions should be made, and if a patient has not returned to his or her baseline within 1 hour, an extended evaluation and observation period/admission should ensue. If there is any question of persistent seizure activity or nonconvulsive status epilepticus (NCSE), a stat EEG should be obtained and further treatment pursued.

LABORATORY EVALUATION

A bedside glucose evaluation is indicated for virtually all patients if not obtained in the prehospital arena. For patients who are taking antiseizure medication, obtaining a drug level, if available, is generally warranted. If a history of drug ingestion or substance abuse is suspected, a toxicology screen should be obtained. Patients with a first-time seizure who have returned to baseline and have no discernable risk factors generally do not require emergent laboratory studies.

Unlike children >6 months of age, where idiopathic and febrile seizures tend to dominate, younger children often have significant underlying pathology. A more liberal approach to laboratory evaluation is generally employed in children younger than 6 months of age as well as any child presenting in status epilepticus (SE) or with prolonged altered mental status.⁶ Generally, these labs include an electrolyte profile including calcium, magnesium, liver function tests, ammonia level, complete blood count, and possibly a venous or arterial blood gas sample. Additional tests that may be considered include organic and amino acids, lead levels, inborn errors of metabolism, etc. These additional tests do little to contribute to the care of the patient in the ED setting and may be best reserved for the neurologist. The laboratory yield for this cohort of patients is potentially useful, with abnormalities of sodium and calcium being the most common findings.⁷ In contrast, cerebrospinal fluid studies in well-appearing afebrile children even under 6 months of age appear to have little diagnostic value.^8,9

For patients who present with a febrile seizure (see later section), the etiology of the fever should be sought. If this is not clear from the physical examination, further laboratory studies may be warranted. Any child who presents with meningeal signs or other evidence of a CNS infection should undergo lumbar puncture (LP). This should be done once it is determined that it is safe to do so. The recommendations for “routine” LP have recently been revised. In children presenting with a simple febrile seizure, aged 6 months to 1 year, the recommendation had been to strongly consider LP.¹⁰ The newer data and practice parameter now makes this an option in children who have not received their scheduled Hib or Pneumococcal vaccines.^10–12 In addition, there are data that suggest the yield from LP is low among children who present with their first complex febrile seizure and LP should be done judiciously.¹³

IMAGING EVALUATION