Residency · Residency · Medicine Pediatrics

Status Epilepticus: Emergency Management Across Ages

Introduction

Status epilepticus (SE) is a neurologic emergency defined as continuous seizure activity lasting more than 5 minutes or two or more seizures without return to baseline. It carries significant morbidity and mortality, with rates increasing with duration of seizure activity. Rapid, protocol-driven management is essential, and the med-peds physician must be proficient in both pediatric and adult treatment algorithms.

Definitions

Early SE: 5-10 minutes of continuous seizure activity. Established SE: 10-30 minutes of continuous seizure activity. Refractory SE (RSE): Seizure activity persisting after two appropriately dosed antiseizure medications. Super-refractory SE: Seizure activity continuing 24+ hours after onset of anesthesia, including recurrence during weaning. Nonconvulsive SE (NCSE): Electrographic seizures without overt motor manifestations; requires EEG for diagnosis.

Epidemiology

Incidence: ~20 per 100,000 in adults; ~18-23 per 100,000 in children. Bimodal distribution: highest incidence in children <1 year and adults >60 years. Febrile SE is the most common cause in young children. Mortality: 3-5% in children; 20-30% in adults (higher in elderly and those with acute symptomatic causes)

Etiologies

Pediatric

Febrile SE (most common in ages 6 months-5 years) Acute symptomatic: CNS infection, metabolic (hypoglycemia, hyponatremia), traumatic brain injury. Known epilepsy with breakthrough seizures or medication non-adherence. First presentation of epilepsy syndrome.

Adult

Subtherapeutic antiseizure medication levels (most common in known epileptics) Acute symptomatic: Stroke, CNS infection, metabolic derangement, alcohol withdrawal. Tumor-related; Autoimmune encephalitis.

Emergency Management Protocol

Phase 1: Stabilization (0-5 minutes)

ABCs: Airway, breathing, circulation. Position patient on side; suction secretions; Apply monitors: pulse oximetry, cardiac telemetry, blood pressure; Obtain IV or IO access; Check point-of-care glucose; treat hypoglycemia immediately; Draw labs: BMP, CBC, antiseizure drug levels, toxicology, lactate.

Phase 2: First-Line Therapy (5-10 minutes)

Benzodiazepines are first-line for all ages.

RouteMedicationPediatric DoseAdult Dose
IVLorazepam0.1 mg/kg (max 4 mg)4 mg; repeat once
IVDiazepam0.2 mg/kg (max 10 mg)10 mg; repeat once
IMMidazolam0.2 mg/kg (max 10 mg)10 mg
IntranasalMidazolam0.2 mg/kg (max 5 mg per naris)5 mg per naris
RectalDiazepam0.5 mg/kg (max 20 mg)20 mg

IM midazolam is as effective as IV lorazepam (RAMPART trial) and is preferred when IV access is not available.

Phase 3: Second-Line Therapy (10-30 minutes)

If seizures persist after two doses of benzodiazepines:

MedicationPediatric DoseAdult DoseNotes
Levetiracetam40-60 mg/kg IV (max 4500 mg)60 mg/kg (max 4500 mg)Fewer drug interactions; safe in liver disease
Fosphenytoin20 mg PE/kg IV20 mg PE/kg IV (max 1500 mg PE)Monitor for hypotension and arrhythmia
Valproate20-40 mg/kg IV20-40 mg/kg IV (max 3000 mg)Avoid in liver disease, mitochondrial disease, pregnancy

ESETT trial: Levetiracetam, fosphenytoin, and valproate are equally effective as second-line agents in both children and adults.

Phase 4: Refractory SE (>30 minutes)

If seizures persist after adequate second-line therapy: Continuous infusion anesthetics with continuous EEG monitoring. Midazolam infusion: 0.1-0.4 mg/kg/hour (pediatric and adult) Propofol infusion: 1-5 mg/kg/hour (adults; use cautiously in children due to propofol infusion syndrome) Pentobarbital infusion: 1-5 mg/kg/hour (for super-refractory SE) Intubation and mechanical ventilation typically required. Transfer to ICU.

Special Considerations

Neonatal Seizures

Phenobarbital remains first-line (20 mg/kg IV loading dose) Levetiracetam increasingly used as alternative. Pyridoxine trial for suspected pyridoxine-dependent epilepsy. Continuous EEG monitoring is essential; clinical seizures are often subtle.

Nonconvulsive SE

Suspect in patients with prolonged altered mental status after convulsive seizure or in critically ill patients. Diagnosis requires continuous EEG. Treatment follows same algorithm but may require more aggressive intervention.

Febrile SE in Children

Most have a benign course; Acute treatment follows standard benzodiazepine protocol; Does not typically require long-term antiseizure medication; Evaluate for underlying CNS infection if clinically indicated.

Post-SE Management

Identify and treat the underlying cause; Load or adjust maintenance antiseizure medications; Continuous EEG monitoring for 24-48 hours after RSE; Neuroimaging (MRI) once stabilized; Neurology consultation.

Complications

Rhabdomyolysis: Check CK, aggressive hydration. Aspiration pneumonia; Metabolic acidosis (usually self-correcting); Neuronal injury: Duration of SE correlates with brain injury; Propofol infusion syndrome (metabolic acidosis, rhabdomyolysis, cardiac failure) in prolonged use.

Clinical Pearls

Time is brain: Every minute of SE causes progressive neuronal injury; treat immediately and aggressively. IM midazolam is as effective as IV lorazepam and should be used when IV access is delayed. Levetiracetam, fosphenytoin, and valproate are equally effective second-line agents (ESETT trial); choose based on patient-specific factors. Always check glucose; hypoglycemia is a reversible cause of seizures that mimics SE. Continuous EEG is mandatory for refractory SE and should be strongly considered for any patient who does not return to baseline after seizure cessation.

References

  1. Silbergleit R, Durkalski V, Lowenstein D, et al. Intramuscular versus intravenous therapy for prehospital status epilepticus (RAMPART). N Engl J Med. 2012;366(7):591-600.
  2. Kapur J, Elm J, Chamberlain JM, et al. Randomized trial of three anticonvulsant medications for status epilepticus (ESETT). N Engl J Med. 2019;381(22):2103-2113.
  3. Brophy GM, Bell R, Claassen J, et al. Guidelines for the evaluation and management of status epilepticus. Neurocrit Care. 2012;17(1):3-23.
  4. Glauser T, Shinnar S, Gloss D, et al. Evidence-based guideline: Treatment of convulsive status epilepticus in children and adults. Epilepsy Curr. 2016;16(1):48-61.

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