Pediatric seizures

Educational Objectives

The goal of this program is to improve the management of seizures in children. After hearing and assimilating this program, the clinician will be better able to:

1. Distinguish true seizures from conditions that mimic seizure.

2. Obtain the appropriate laboratory tests in the work-up for seizures.

Summary

Epidemiology: ≈3.5% of children have unprovoked seizure by age 15 yr; ≥2 unprovoked seizures in children ≤15 yr of age cause for concern; ≤5% of children have febrile seizure before 5 yr of age (tends to run in families), of whom 1% to 3% develop epilepsy if not treated (75% idiopathic)

Definition of status epilepticus: previously, seizure lasting >30 min or ≥2 seizures without regaining consciousness in between; presently, seizure lasting longer than 5 to 10 min or ≥2 episodes without return of normal cognitive function; most seizures last ≈1 to 2 min

Etiology of nonfebrile seizures: in early infancy, most likely due to metabolic diseases or congenital abnormalities; presence of fever at time of seizure necessary to meet definition of febrile seizure; child with one febrile seizure more likely to have another because of low threshold; conditions that mimic seizures in very young infants — apnea (color change and bradycardia vs tachycardia in seizures); breath-holding spells; gastrointestinal reflux

Management: routine laboratory tests unnecessary in healthy child with access to food and water; serum glucose test sometimes recommended; emergency computed tomography (CT) not necessary if child back to normal after seizure (perform as outpatient); nonemergent magnetic resonance imaging (MRI) — preferred because of absence of radiation; indicated if child <1 yr of age, seizure is focal, and undiagnosed neurologic impairment or disorder present; start medications if child has second unprovoked seizure; electroencephalography (EEG) — need not be performed emergently; not beneficial in very young infants due to lack of correlation; seizure due to head trauma, or presence of focal prolonged seizure secondary to tumor or bleeding, altered level of consciousness, or prolonged focal postictal period deficit concerning; first seizure in healthy child — emergency CT and laboratory tests unnecessary; arrange follow-up with good pediatrician or neurologist; starting medications also unnecessary

Whether seizures harmful: muscle rigidity and shaking in status epilepticus possibly harmful; brains of children, particularly neonates, more susceptible to prolonged electrical firing, and may permanently lower seizure threshold, affect ability to learn, and impair memory; some seizures in very young infants more subtle and often missed or confused with normal infant movements; generalized tonic-clonic seizures not common in very young infants; very young infants often present with focal clonic, tonic, migratory clonic seizures (child sometimes semialert), horizontal nystagmus (ocular seizures), and autonomic seizures (ie, “bicycling,” lip smacking, blinking); not considered seizure if able to provoke movements; true seizures — not typically induced by tactile stimulation; usually associated with tachycardia or increased blood pressure (BP); unable to stop movements; any type of cardiac dysrhythmia or nonperfusing rhythm can mimic seizure

Causes: birth trauma and hypoxia (≈50%); neonates usually present with seizure due to birth trauma in first 24 to 48 hr; intracranial hemorrhages account for ≈10%; intracranial bleeding in infants more likely due to arteriovenous malformation; if due to toxoplasmosis, other (syphilis), rubella, cytomegalovirus, herpes simplex virus (TORCH) infection, tends to occur in first few days of life; if infection due to other bacterial pathogen, usually occurs in first 2 wk of life; consider hypocalcemia and hypoglycemia in differential diagnosis, especially in first 2 wk of life; in pyridoxine deficiency, infants unable to produce g-aminobutyric acid, causing multifocal clonic seizures; kernicterus can also cause seizures; glucose transport deficiency — rare; defect in transport of glucose across blood-brain barrier; low glucose level in cerebrospinal fluid but normal in serum; usually diagnosis of exclusion; inborn errors of metabolism — usually presents itself due to infection; may present with altered mental status, neurologic symptoms, and seizure; neurocutaneous disorders; drug withdrawal — eg, narcotics, opiates; infant usually jittery and anxious; with methadone, withdrawal seizures usually occur several weeks after birth; benign familial neonatal seizures — “fifth day fit” because seizures usually occur on day 5; generally resolve in few weeks; usually diagnosis of exclusion; during first 30 min of seizure, catecholamines released, causing increased BP and tachycardia; if seizure prolonged, cerebral blood flow decreased, reducing glucose supply to brain; BP and glucose decreased; temperature increased; potassium and creatine phosphokinase abnormal; the longer the duration of seizure, the more resistant to treatment, and morbidity inversely proportional to age

Management: no studies on very young infants; rectal dose of diazepam 0.5 mg/kg; shown, however, that decreasing dose of diazepam rectally or intravenously (IV) as effective in stopping seizures, with less respiratory compromise; intramuscular (IM) midazolam also effective

Pediatric assessment triangle: from American Academy of Pediatrics and American College of Emergency Physicians; determine appearance, work of breathing, and color (circulation); infants not necessarily “blue” but may be pale if hypoxic; use pulse oximetry to determine if child hypoxic; start IV or intraosseous line; check blood glucose; if hypoglycemia present, administer 5 mL/kg of dextrose (D10) in very young infants (higher concentrations more injurious to tissues and blood vessels); especially in infants <2 mo of age, even if seizure focal or resolved with benzodiazepine, check sodium, calcium, and glucose; dose of benzodiazepines 0.1 mg/kg; midazolam has advantage of drip administration; maternal history — probably more important than infant’s; determine prenatal history, presence of infections, whether screened for TORCH, substance abuse, family history, use of home remedies, and how formula mixed (mother may dilute with water to save money); physical examination (PE) — check fontanelles for bulging or bruit; look for jaundice; odor (some inborn errors of metabolism have unique odors); skin lesions; laboratory tests — sodium level; if etiology unclear from beginning, consider inborn errors of metabolism in differential diagnosis; unless etiology clear from beginning, obtain sepsis work-up (includes lumbar puncture [LP]) and cranial ultrasonography or CT

Drugs: start with benzodiazepines; phenobarbital second-line agent, especially in very young infants; phenytoin not used in neonates (causes myocardial depression); fosphenytoin safer in neonates; valproate option; levetiracetam (Keppra) — safe for neonates (few studies); retrospective review of infants 1 day to 17 yr of age who received levetiracetam within 30 min of seizure; most received one other medication to abort seizure; 90% of patients seizure-free within 1 hr; not first-line agent, but consider in prolonged seizure after benzodiazepine and phenobarbital; prolonged seizure in very young infant — consider dose of calcium gluconate, magnesium, and pyridoxine (especially if mother on isoniazid); continuous EEG monitoring indicated, except in very young infants; correct hyponatremia with 4 mL/kg of 3% saline; antibiotics, unless etiology clear; acyclovir — dose 10 mg/kg, especially if CSF shows increased white blood cells and protein, with no organisms seen on Gram stain, or if focal findings seen on neurologic examination or maternal herpesvirus infection present; early administration preferred

Readings

Adams SM, Knowles PD: Evaluation of a first seizure. Am Fam Physician, 2007 May 1;75(9):1342-7; Dayan PS et al: Pediatric Emergency Department Northeast Team of the Pediatric Emergency Care Applied Research Network (PECARN). Interobserver agreement in the assessment of clinical findings in children with first unprovoked seizures. Pediatrics, 2011 May;127(5):e1266-71; Dlugos D, Sirven JI: Prognosis of neonatal seizures: “It’s the etiology, Stupid” — or is it? Neurology, 2007 Nov 6;69(19):1812-3; Evans WN et al: Hair-grooming syncope in children. Clin Pediatr (Phila), 2009 Oct;48(8):834-6; Freedman BD et al: Hypoglycemic seizure. Clin Pediatr (Phila), 2010 Nov;49(11):1078-80; Hsieh DT et al: New-onset afebrile seizures in infants: role of neuroimaging. Neurology, 2010 Jan 12;74(2):150-6; Hussain T et al: Hypoglycaemic syncope in children secondary to beta-blockers. Arch Dis Child, 2009 Dec;94(12):968-9; Jarjour IT, Jarjour LK: Low iron storage in children and adolescents with neurally mediated syncope. J Pediatr, 2008 Jul;153(1):40-4; Lateef TM et al: Diagnostic value of lumbar puncture in afebrile infants with suspected new-onset seizures. J Pediatr, 2008 Jul;153(1):140-2; Massin MM et al: Syncope in pediatric patients presenting to an emergency department. J Pediatr, 2004 Aug;145(2):223-8; Olde Nordkamp LR et al: Vasovagal syncope as a cause of syncope in long-QT syndrome. J Am Coll Cardiol, 2011 Jul 5;58(2):199-200; author reply 200; Schwartz PJ et al: The Jervell and Lange-Nielsen syndrome: natural history, molecular basis, and clinical outcome. Circulation, 2006 Feb 14;113(6):783-90; Silverstein FS et al: Improving the treatment of neonatal seizures: National Institute of Neurological Disorders and Stroke workshop report. J Pediatr, 2008 Jul;153(1):12-5; Steinberg LA, Knilans TK: Syncope in children: diagnostic tests have a high cost and low yield. J Pediatr, 2005 Mar;146(3):355-8.

Disclosures

In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the planning committee to disclose relevant financial relationships within the past 12 months that might create any personal conflicts of interest. Any identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business or commercial interest. For this program, the faculty and planning committee reported nothing to disclose.

Acknowledgements

Dr. McCullough was recorded at Pediatric Emergency Medicine, held March 11-12, 2011, in Las Vegas, NV, and sponsored by the Center for Emergency Medical Education.  For more information on upcoming CME by the Center for Emergency Medical Education, visit: www.ceme.org. The Audio-Digest Foundation thanks the speaker and sponsor for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

EM291201

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.

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