Status Epilepticus
Key Facts
Definition: Continuous seizure activity ≥5 minutes OR ≥2 seizures without recovery of consciousness between them. This is a medical emergency requiring immediate treatment.
Source: ILAE; Neurocritical Care Society.
Warning
Benzodiazepine failure (refractory status epilepticus) occurs in ~30% of patients. Do NOT wait — escalate to second-line agents after 2 doses of benzodiazepine.
Stepwise Management
First Line (0–5 min): Benzodiazepines
- IV access: Midazolam 0.1 mg/kg IV (max 10 mg) OR lorazepam 0.1 mg/kg IV (max 4 mg)
- No IV access: Midazolam 0.2 mg/kg IM (max 10 mg) OR buccal/intranasal midazolam
- Repeat once at 5 minutes if seizure continues
Second Line (5–20 min): Anti-epileptic drugs
- Levetiracetam 60 mg/kg IV (max 4500 mg) over 10 min — first-line in many Australian centres
- Sodium valproate 40 mg/kg IV (max 3000 mg) over 5 min
- Phenytoin 20 mg/kg IV (max 1500 mg) over 20 min — avoid in cardiac disease
Third Line (>20 min): RSI + Infusion
- Intubate and commence propofol or midazolam infusion
- Continuous EEG monitoring
- Target burst suppression for 24–48 hours
Key Investigations
- BSL (hypoglycaemia is a reversible cause)
- Electrolytes (Na⁺, Ca²⁺, Mg²⁺)
- Anti-epileptic drug levels if known epilepsy
- CT brain if first seizure or focal features
- LP if infection suspected (after CT)
Causes (VITAMINS)
- Vascular (stroke, SAH)
- Infection (meningitis, encephalitis)
- Trauma (TBI)
- Autoimmune (anti-NMDA receptor encephalitis)
- Metabolic (hypoglycaemia, hyponatraemia, hypocalcaemia)
- Ingestion/toxins (drug withdrawal, overdose)
- Neoplasm
- Seizure disorder (subtherapeutic AED levels)