Seizure (peds)

General

It is important to consider performing imaging in young patients with new-onset focal seizures to look for a brain mass or trauma

immed after trauma = impact sz (no antieleptics)

>20min after = TBI (antieleptic)

INH --> pyridoxine

Status epilepticus is a "prolonged" seizure or recurrent seizures lasting >5 minutes without the patient's regaining consciousness. Rapid cessation of status epilepticus is important to prevent irreversible neuronal damage

In children with a prolonged postictal state, especially in those who are not known to have had a prolonged postictal state with past epileptic episodes, consider the diagnosis of nonconvulsive status epilepticus.8 Consider an emergency EEG to identify seizure activity. If EEG testing is not available, a trial of anticonvulsants can be initiated and might result in improved mental status. Morbidity and mortality are increased when nonconvulsive status epilepticus is untreated, but less so than with untreated convulsive status epilepticus.8

Events Masquerading as Seizures

Syncope

Breath-holding spells

Cataplexy

Narcolepsy

Vasovagal event

Standing for long periods of time

Standing quickly from laying or sitting

Hair-grooming syncope

Earring-changing syncope

Micturition syncope

Emotional distress or pain

Hypoglycemia

Hypovolemia

Sandifer syndrome (gastroesophageal reflux)

Acute life-threatening event

Acute dystonic reactions/drug reactions [i.e., promethazine (Phenergan)]

Movement disorders

Tics

Myoclonic jerks

Chills or rigors

Shudder attacks

Mannerisms

Self-stimulation

Choreoathetosis

Night terrors, sleep walking

Migraine variants

Benign paroxysmal vertigo

Nonepileptic paroxysmal event (pseudoseizure)

In one study, lateral tongue biting was found to have a specificity of 100% and a sensitivity of 24% for the occurrence of a seizure.11

Seizure with a fever can be associated with central nervous system (CNS) infection (meningitis, encephalitis, or abscess), especially in very young patients. More commonly, however, fever simply lowers the seizure threshold in patients with epilepsy or causes a simple febrile seizure. A patient with new-onset afebrile seizures may require a more thorough evaluation than patients with epilepsy taking anticonvulsant medications, who may just have "outgrown" their dosage. A seizure associated with a "breath-holding spell" is usually a benign event. Postimpact seizures occur immediately after head trauma and do not often indicate significant brain injury. However, new-onset seizures that occur more remotely after head trauma may be more ominous and signal severe head trauma. Sometimes a seizure's underlying cause is not discovered, and the seizure is labeled idiopathic

Todd paralysis is a temporary condition characterized by a focal deficit of unknown etiology that can last up to 36 hours after a seizure.12 The paralysis is usually unilateral and lasts on average 15 hours.12 However, it can be bilateral and involve a patient's speech or vision.12 It may be impossible to distinguish Todd paralysis from stroke, and emergent evaluation for a stroke should still be considered.12

Rapid bedside testing for electrolyte levels (glucose, sodium, and calcium) is recommended in status epilepticus when available.4,7 Order a complete blood count (CBC), full chemistry panel, hepatic and renal studies, and anticonvulsant levels, if appropriate, when an IV is placed. Other studies may be needed depending upon the suspected underlying cause of seizures. Consider CNS infection in the child with fever and status epilepticus.

he decision to intubate is clinical. Intubate for apnea and persistent hypoxia. Blood gas concentrations are not needed to guide the decision to intubate, because the seizure itself causes a metabolic and respiratory acidosis. The use of a paralytic with intubation will obscure the ability to assess ongoing seizure activity, and continuous EEG monitoring should be arranged for intubated patients with status epilepticus.

For these reasons, initial benzodiazepine treatment should be limited to two doses.

Drug	Route	Dose*	Maximum	Onset of Action	Duration of Action
Lorazepam	IV, IO, IN[[Image:]]	0.1 milligram/kg	4 milligrams	1–5 min	12–24 h
	IM	0.1 milligram/kg	4 milligrams	15–30 min	12–24 h
Diazepam	IV, IO	0.1–0.3 milligram/kg	10 milligrams	1–5 min	15–60 min
	PR	0.5 milligram/kg	20 milligrams	3–5 min	15–60 min
Midazolam	IV, IO	0.1–0.2 milligram/kg	4 milligrams	1–5 min	1–6 h
	IM	0.2 milligram/kg	10 milligrams	5–15 min	1–6 h
	IN	0.2 milligram/kg	10 milligrams	1–5 min	1–6 h
	Buccal[[Image:]]	0.5 milligram/kg	10 milligrams	3–5 min	1–6 h

If a seizure persists for another 5 minutes after two doses of a benzodiazepine have been given, fosphenytoin or phenobarbital are the preferred second-line treatment choices

Fosphenytoin is usually the preferred second-line treatment over phenobarbital, mainly because it differs from the benzodiazepines

Phenobarbital is preferred over phenytoin or fosphenytoin in children who have allergies to fosphenytoin or phenytoin, present with a febrile illness, or are <2 years of age. Side effects of phenobarbital are sedation and cardiorespiratory depression, which may be amplified by benzodiazepines

Drug	Route	Loading Dose	Repeat Dose	Maximum	IV Infusion
Fosphenytoin	IV, IM	15–20 milligrams/kg PE	5–10 milligrams/kg PE	30 milligrams/kg PE	3 milligrams/kg/min PE
Phenobarbital	IV	15–20 milligrams/kg	5–10 milligrams/kg	40 milligrams/kg	1–30 milligrams/min
Valproic acid	IV	20 milligrams/kg	15–20 milligrams/kg	40 milligrams/kg	5 milligrams/kg/h
Levetiracetam	IV	20–30 milligrams/kg	—	3 grams	—
Pentobarbital	IV	5–15 milligrams/kg	1–2 milligrams/kg	15 milligrams/kg	0.5–5.0 milligrams/kg/h
Propofol	IV	0.5–2.0 milligrams/kg	0.5–1.0 milligram/kg	5 milligrams/kg	1.5–4.0 milligrams/kg/h
Midazolam	IV	0.1–0.2 milligram/kg	0.1–0.2 milligram/kg	10 milligrams	0.05–0.4 milligram/kg/h

Third-Line Treatment

 One study showed seizure termination within 30 minutes in all 18 children who received a loading dose of 25 milligrams/kg IV

In another study 41 patients were treated with valproic acid 20 to 40 milligrams/kg IV over 1 to 5 minutes and then received an infusion of 5 milligrams/kg/h of valproic acid. This study showed clinically and EEG determined termination of seizures in 78% of patients, in 66% within 6 minutes

Hypoglycemia is defined as a glucose level of <50 milligrams/dL regardless of whether symptoms exist. There are multiple causes of hypoglycemia, but the most common cause in children is decreased intake of glucose. Seizures can occur with hypoglycemia, so glucose level should be measured in all patients presenting with seizures. If hypoglycemia is present, patients should be treated with a rapid infusion of 2 mL/kg of 25% dextrose in water.

Excessive water drinking can lead to hyponatremia (<135 mEq/L). Hyponatremia is most commonly seen in infants <6 months of age and sometimes in athletes. Babies who drink several bottles of water a day or who drink dilute infant formula are at risk for hyponatremia. Athletes can also suffer from water intoxication.

Hyponatremia can cause seizures, especially if the sodium level is <120 mEq/L. The goal of therapy is to correct the level to >120 mEq/L quickly to treat or prevent further seizure activity, and then correct the sodium to normal levels over the next 24 hours (see Chapter 142, Fluid and Electrolyte Therapy in Infants and Children).⁶ If a patient is actively experiencing seizure, the treatment of choice is 3% NaCl.⁶ An infusion of 20 mL/kg of 0.9% NaCl should be started immediately for patients in status epilepticus if delivery of 3% NaCl is delayed. The calculation for 3% NaCl is presented in Formula 129-1.

3% NaCl (513 mEq/1000 mL): Na deficit in total mEq = [(weight in kg) x (130 – serum Na level) x 0.6] over 20 minutes

OR

3% NaCl: 4 to 6 mL/kg over 20 minutes

If there is no seizure activity but the sodium level is below 120 mEq/L, 4 to 6 mL/kg of 3% NaCl or 20 mL/kg of normal saline can be given over an hour. The sodium level should be rechecked after the bolus to see if a second bolus is necessary

As with other electrolyte abnormalities, the hypocalcemia must be addressed by administration of calcium in order to treat seizures, because benzodiazepines are not very effective in this setting. Ten percent calcium gluconate (0.3 mL/kg administered slowly over 5 to 10 minutes) is the preferred type of IV calcium, because calcium chloride often causes local irritation.⁶