Learning objectives

• Describe the overall mechanisms and etiology of status epilepticus in pediatric patients
• Manage status epilepticus in pediatric patients

Definition & mechanisms

• Status epilepticus is defined as more than 30 minutes of either 1) continuous seizure activity or 2) two or more sequential seizures without full recovery of consciousness between seizures
• Epilepsy is twice as common in children compared with adults
• Cerebral damage is more likely if the seizure is prolonged
• There are lots of different types of seizures and not all of them involve obvious convulsive activity
• Epilepsy can occur at any age but is commonly diagnosed in those aged below 20 or over 65 years
• First stage is characterized by an increase in:
  • Cerebral metabolism
  • Blood flow
  • Glucose and lactate concentration
• Compensatory mechanisms:
  • Massive catecholamine release
  • Raised cardiac output
  • Hypertension
  • Increased central venous pressure
• After 30-60 min, compensatory mechanisms fail:
  • Hypoxia
  • Hypoglycemia
  • Increased intracranial pressure
  • Cerebral edema
  • Hyponatremia
  • Potassium imbalance
  • Evolving metabolic acidosis
  • Consumptive coagulopathy
  • Rhabdomyolysis 
  • Multi-organ failure

Etiology

• Acute
  • Stroke
  • Metabolic abnormalities 
  • Hypoxia
  • Systemic infection
  • Anoxia
  • Trauma
  • Traumatic brain injury
  • Drug overdose
  • CNS infection
  • CNS hemorrhage
• Chronic
  • Inheritance tendency
  • Low concentration of anti-epileptic drugs
  • Structural changes to the brain (trauma) or space occypying lesions (tumor, stroke)
  • Idiopathic

Signs and symptoms

Status epilepticus can present in several forms: 

• Convulsive: unresponsiveness and tonic, clonic, or tonic-clonic movements of the extremities
• Non-convulsive: prolonged seizure activity evidenced by epileptiform discharges on EEG, change in behavior or cognition in some patients
• Electrographic: commonly used for comatose patients who show electrographic evidence of prolonged seizure activity

Diagnosis

• Based on history and clinical examination
• Often present either actively convulsing or minimal time between clustered seizures

Prevention

• Seizure detection based on EEG and immediate treatment
• In patients with a history of well-controlled epilepsy, avoid disruption of antiepileptic medication perioperatively

Management

Suggested reading

• Glauser T, Shinnar S, Gloss D, et al. Evidence-Based Guideline: Treatment of Convulsive Status Epilepticus in Children and Adults: Report of the Guideline Committee of the American Epilepsy Society. Epilepsy Curr. 2016;16(1):48-61.
• Betjemann JP, Lowenstein DH. Status epilepticus in adults. Lancet Neurol. 2015;14(6):615-624.
• Perks A, Cheema S, Mohanraj R. Anaesthesia and epilepsy. BJA: British Journal of Anaesthesia. 2012;108(4):562-71.
• Barakat, A.R., Mallory, S., 2011. Anaesthesia and childhood epilepsy. Continuing Education in Anaesthesia Critical Care & Pain 11, 93–98.