What is status epilepticus?

Status Epilepticus: Definition and Management

Status epilepticus is defined as a seizure lasting longer than 5 minutes or multiple seizures without a return to neurologic baseline, representing a critical medical emergency requiring immediate intervention. 1, 2

Definition and Classification

Status epilepticus (SE) is characterized by:

• Prolonged seizure activity (>5 minutes)
• Multiple seizures without recovery between episodes
• Failure of the mechanisms responsible for seizure termination
• Potential for long-term neurological consequences if not promptly treated

Epidemiology and Impact

• Affects approximately 36.1 per 100,000 person-years 3
• Associated with substantial morbidity and mortality (estimated mortality of 20%) 4
• Accounts for about 1% of all emergency department visits 1

Etiology

Common causes include:

• Cerebrovascular disorders
• Brain trauma
• Central nervous system infections
• Low antiepileptic drug levels in patients with epilepsy
• Metabolic abnormalities (hypoglycemia, hyponatremia)
• Prescribed medications that lower seizure threshold (e.g., tramadol)
• Illicit substances (e.g., cocaine) 1, 4

Less common but important causes:

• Inflammatory/autoimmune disorders
• Inborn errors of metabolism
• Paraneoplastic syndromes 4

Clinical Presentation

• Generalized tonic-clonic movements affecting large areas or both sides of the brain
• Focal seizures that may progress to generalized seizures
• Altered consciousness
• Possible urinary incontinence
• Postictal confusion following seizure termination 1

Management Approach

Immediate Actions

1. Secure airway, breathing, and circulation
2. Position patient on their side in recovery position to prevent aspiration 1
3. Clear area around patient to prevent injury 1
4. Activate EMS for:
   • First-time seizure
   • Seizures lasting >5 minutes
   • Multiple seizures without return to baseline
   • Seizures with traumatic injuries or breathing difficulties
   • Seizures occurring in water 1

First-Line Treatment

• Benzodiazepines are the first-line treatment for status epilepticus
• Lorazepam 4 mg IV given slowly (2 mg/min) is recommended
• If seizures continue after 10-15 minutes, an additional 4 mg IV dose may be administered 2, 5

Second-Line Treatment

If seizures persist despite optimal benzodiazepine dosing, the following agents are equally effective:

• Levetiracetam: 30-60 mg/kg IV (preferred in hepatic dysfunction)
• Fosphenytoin: 20 mg PE/kg IV
• Valproate: 30 mg/kg IV 2

All three second-line options achieve seizure cessation in approximately 45-47% of cases 2

Refractory Status Epilepticus

If seizures continue after second-line therapy:

• Transfer to ICU
• Initiate continuous EEG monitoring
• Consider anesthetic agents (midazolam, propofol, or ketamine) 2

Diagnostic Evaluation

Essential laboratory tests include:

• Serum glucose (all patients)
• Serum sodium (all patients)
• Complete metabolic panel (if altered mental status)
• Toxicology screen (if substance use suspected)
• Antiepileptic drug levels (in patients on seizure medications)
• CBC, blood cultures, lumbar puncture (if fever present) 2

Imaging:

• Brain CT or MRI to identify structural causes
• MRI is preferred for new-onset seizures in non-emergent settings 2

Common Pitfalls to Avoid

• Delayed treatment initiation
• Inadequate benzodiazepine dosing
• Failure to monitor respiratory status (benzodiazepines can cause respiratory depression)
• Missing non-convulsive status epilepticus
• Overlooking treatable underlying causes
• Restraining the person during a seizure
• Placing objects in the mouth during a seizure 1, 2

Prognosis

Three major determinants of prognosis:

1. Duration of status epilepticus
2. Patient age
3. Underlying cause 4

Early recognition and aggressive treatment are essential to prevent neurological damage and improve outcomes 6.

Disposition

Patients can be discharged if they:

• Have returned to baseline mental status
• Had a single self-limited seizure with no recurrence
• Have normal or non-acute findings on neuroimaging
• Have reliable follow-up available
• Have a responsible adult to observe them 2

All patients with new-onset seizures should be referred to neurology for follow-up evaluation, including EEG to identify epilepsy syndromes and classify seizure type 2.