Residency · Residency · Pediatrics
Status Epilepticus Management
Overview
Status epilepticus (SE) is a neurological emergency defined as a seizure lasting 5 minutes or longer, or two or more seizures without return to baseline consciousness. It is the most common neurological emergency in children, with an annual incidence of approximately 18-23 per 100,000 children. Mortality in children is 3-5% (lower than in adults), and morbidity includes neuronal injury, especially after 30 minutes. The critical principle is that time is brain: the longer SE persists, the more resistant it becomes to treatment and the greater the risk of neuronal injury. The incidence has a bimodal age distribution, being highest in children under 2 years and in elderly adults.
Classification
Convulsive SE (CSE) involves ongoing generalized tonic-clonic activity and is the most common and most dangerous form. Non-convulsive SE (NCSE) has subtle or absent motor manifestations with ongoing electrographic seizure activity and requires EEG for diagnosis. Focal SE involves persistent focal seizure activity (epilepsia partialis continua). In terms of temporal staging, early SE spans 5-30 minutes, established SE spans 30-60 minutes, refractory SE (RSE) is defined by seizure persistence despite two appropriate medications (a first-line benzodiazepine plus a second-line agent), and super-refractory SE (SRSE) is defined by seizure continuation for 24 hours or more after anesthesia onset, or recurrence during anesthesia weaning.
Etiology
Febrile SE (a prolonged febrile seizure) is the most common cause in young children. Acute symptomatic causes include CNS infection (meningitis, encephalitis), metabolic derangement (hypoglycemia, hyponatremia, hypocalcemia), toxic ingestion, trauma, and stroke. Known epilepsy with subtherapeutic anticonvulsant levels, medication non-compliance, or intercurrent illness is another common cause. SE may also be the initial presentation of new-onset epilepsy. Autoimmune and inflammatory etiologies include anti-NMDA receptor encephalitis and FIRES (febrile infection-related epilepsy syndrome).
Stabilization Algorithm
Time 0-5 Minutes: Stabilization (ABCs)
Initial management focuses on airway (positioning, suction, jaw thrust, with nothing inserted into the mouth), breathing (supplemental oxygen with preparation for possible intubation), and circulation (establishing IV or IO access, monitoring, and obtaining point-of-care glucose). Hypoglycemia must be checked immediately and treated with dextrose (D10W at 5 mL/kg in neonates and infants; D25W at 2-4 mL/kg in older children). Vital signs, pulse oximetry, and cardiac monitoring should be initiated. A brief focused history should cover seizure medications, recent illness, ingestion, and trauma.
Time 5-20 Minutes: First-Line -- Benzodiazepines
The goal is to terminate the seizure with benzodiazepines as quickly as possible. Benzodiazepines enhance GABA-A receptor activity, but their efficacy decreases with prolonged seizures due to receptor internalization.
| Agent | Route | Dose | Maximum | Notes |
|---|---|---|---|---|
| Lorazepam | IV/IO | 0.1 mg/kg | 4 mg/dose | Preferred IV agent; may repeat x1 in 5 min |
| Diazepam | IV/IO | 0.15-0.2 mg/kg | 10 mg | Shorter CNS effect; higher recurrence |
| Midazolam | IM | 0.2 mg/kg | 10 mg | Preferred if no IV access (RAMPART trial) |
| Midazolam | Intranasal | 0.2 mg/kg | 5 mg/naris | Use concentrated formulation |
| Midazolam | Buccal | 0.2 mg/kg | 10 mg | Common in European protocols |
| Diazepam | Rectal | 0.5 mg/kg | 20 mg | Diastat gel; home rescue use |
IV or IO lorazepam is given at 0.1 mg/kg (maximum 4 mg per dose) and may be repeated once in 5 minutes. It is the preferred IV benzodiazepine because of its longer duration of action compared to diazepam. IV or IO diazepam is given at 0.15-0.2 mg/kg (maximum 10 mg) and may be repeated once, though it has a shorter CNS effect and higher recurrence rate. IM midazolam at 0.2 mg/kg (maximum 10 mg) is preferred when no IV access is available; the RAMPART trial demonstrated it is non-inferior to IV lorazepam and faster to administer in the prehospital setting. Intranasal midazolam is given at 0.2 mg/kg (maximum 5 mg per naris using the concentrated formulation). Buccal midazolam at 0.2 mg/kg (maximum 10 mg) is used in many European countries. Rectal diazepam at 0.5 mg/kg (maximum 20 mg) is available as rectal gel (Diastat). A maximum of 2 doses of benzodiazepines should be given before moving to second-line agents.
<image>Status epilepticus treatment timeline showing minute-by-minute algorithm: Time 0-5 (stabilization, ABCs, glucose check), Time 5-20 (first-line benzodiazepines with dosing for IV, IM, intranasal, and rectal routes), Time 20-40 (second-line agents: levetiracetam, fosphenytoin, or valproate), and Time 40+ (refractory SE management with continuous infusion agents)</image>
Time 20-40 Minutes: Second-Line -- Urgent Control Therapy
If the seizure persists after 2 doses of benzodiazepines, second-line agents are administered. There is no consensus on the best second-line agent.
| Agent | Dose | Infusion Rate | Efficacy | Key Considerations |
|---|---|---|---|---|
| Levetiracetam | 40-60 mg/kg IV (max 4500 mg) | Over 15 min | ~50-60% | No cardiac monitoring needed; no drug interactions; safest in unknown etiology |
| Fosphenytoin | 20 PE/kg IV (max 1500 PE) | 3 PE/kg/min (max 150 PE/min) | ~50-60% | Requires cardiac monitoring; avoid in cardiac disease; risk of purple glove syndrome |
| Valproate | 40 mg/kg IV (max 3000 mg) | Over 5-10 min | ~50-60% | Avoid in metabolic disease, hepatic dysfunction, age <2 yr; contraindicated in mitochondrial disease |
Levetiracetam (Keppra) is given at 40-60 mg/kg IV (maximum 4500 mg) over 15 minutes. It has a favorable side effect profile, requires no cardiac monitoring, and has no drug interactions. The ConSEPT and EcLiPSE trials showed comparable efficacy to phenytoin at approximately 50-60% seizure cessation. Fosphenytoin is given at 20 PE/kg IV (maximum 1500 PE) at 3 PE/kg/min (maximum 150 PE/min) and requires cardiac monitoring due to the risk of hypotension and arrhythmia. It should be avoided in known cardiac disease, and clinicians should monitor for purple glove syndrome from extravasation. Valproate (Depakene) is given at 40 mg/kg IV (maximum 3000 mg) over 5-10 minutes. It allows rapid infusion and is generally well tolerated but should be avoided in suspected metabolic disease, hepatic dysfunction, or children under 2 years (hepatotoxicity risk), and is contraindicated in mitochondrial disease due to the risk of fatal hepatotoxicity.
Key Trial Evidence
The ConSEPT trial (2019, Australia) compared levetiracetam to phenytoin and found no significant difference in seizure cessation at 5 minutes (50% vs. 60%). The EcLiPSE trial (2019, UK) similarly found no significant difference (51% vs. 56%). Both trials suggest levetiracetam is a reasonable alternative to phenytoin but is not superior.
Time 40+ Minutes: Refractory Status Epilepticus
If the seizure persists after first-line benzodiazepine plus a second-line agent, ICU admission and continuous EEG monitoring are required. A repeat dose of the second-line agent should be considered if the level is subtherapeutic, or an alternative second-line agent may be tried.
Continuous Infusion Options
Midazolam continuous infusion (0.1-0.4 mg/kg/hr, up to 2 mg/kg/hr) is most commonly used first, with a loading bolus of 0.2 mg/kg. It has the advantage of a short half-life and easier titration. Pentobarbital (5-15 mg/kg bolus, then 0.5-5 mg/kg/hr infusion) is more potent and used when midazolam fails, but it causes significant hemodynamic compromise and often requires vasopressors. Propofol has limited use in pediatrics due to the risk of propofol infusion syndrome (metabolic acidosis, rhabdomyolysis, cardiac failure) and should be avoided with prolonged use beyond 48 hours or doses above 5 mg/kg/hr. Ketamine, an NMDA receptor antagonist, has an emerging role in SRSE and may be neuroprotective, given as a 2-3 mg/kg bolus then 1-5 mg/kg/hr infusion. The target is EEG burst suppression or seizure cessation for 24-48 hours, followed by gradual weaning.
Super-Refractory SE
For super-refractory SE, immunotherapy should be considered (IVIG, corticosteroids, plasmapheresis), especially if autoimmune etiology such as anti-NMDA receptor encephalitis is suspected. The ketogenic diet has shown efficacy in case reports and series. Hypothermia is investigational. Neurological surgery with focal resection may be considered if a structural lesion is identified.
Post-SE Management
Post-SE management involves identifying and treating the underlying cause, monitoring for complications (aspiration pneumonia, rhabdomyolysis with CK measurement, electrolyte abnormalities, cerebral edema), neuroimaging (MRI preferred) after stabilization to identify structural causes, and continuous EEG monitoring if the patient has not returned to baseline to rule out non-convulsive SE. A maintenance anticonvulsant appropriate to the etiology and seizure type should be started, and neurology consultation is warranted for all SE cases.
<image>Algorithm for refractory status epilepticus management in the ICU showing continuous infusion options (midazolam, pentobarbital, propofol with pediatric cautions, ketamine), EEG monitoring targets (burst suppression for 24-48 hours), weaning protocol, and consideration of immunotherapy and ketogenic diet for super-refractory cases</image>
Clinical Pearls
Time is critical: benzodiazepines work best when given early, with efficacy dropping from approximately 80% at 5 minutes to 40% at 30 minutes due to GABA receptor internalization. IM midazolam is the preferred out-of-hospital treatment when IV access is not available, as the RAMPART trial showed it is faster and equally effective. Glucose should always be checked immediately because hypoglycemia is a treatable cause of seizures that can mimic SE. Benzodiazepine administration should not be delayed to obtain IV access; IM, intranasal, buccal, or rectal routes should be used instead. Phenytoin and valproate are contraindicated in certain metabolic diseases, so when the etiology is unknown, levetiracetam may be the safest second-line choice. Subtle SE (minimal motor manifestations after prolonged convulsive SE) requires EEG for detection, as a "quiet" patient post-SE may still be seizing electrographically.
Key Controversy: Levetiracetam vs. Fosphenytoin as Second-Line
The ConSEPT and EcLiPSE trials showed comparable efficacy at approximately 50-60% cessation rates. Levetiracetam offers advantages including no need for cardiac monitoring, fewer drug interactions, no hepatotoxicity, and safe use in metabolic disease. Fosphenytoin offers decades of clinical experience, well-characterized pharmacokinetics, and slightly higher numerical cessation rates (though not statistically significant). Valproate may be superior to both in some studies but is contraindicated in metabolic disease and young children. The ESETT trial (adults and children 2 years and older) compared all three and found no significant difference among them at approximately 45-50% efficacy each. Current practice increasingly favors levetiracetam as the initial second-line agent given its safety profile, but institutional protocols vary. Ongoing research focuses on biomarkers to predict treatment response and personalized second-line agent selection.
References
- Silbergleit R, et al. Intramuscular versus Intravenous Therapy for Prehospital Status Epilepticus (RAMPART). N Engl J Med. 2012;366(7):591-600.
- Dalziel SR, et al. Levetiracetam versus Phenytoin for Second-Line Treatment of Convulsive Status Epilepticus in Children (ConSEPT). Lancet. 2019;393(10186):2135-2145.
- Lyttle MD, et al. Levetiracetam versus Phenytoin for Second-Line Treatment of Pediatric Convulsive Status Epilepticus (EcLiPSE). Lancet. 2019;393(10186):2125-2134.
- Kapur J, et al. Randomized Trial of Three Anticonvulsant Medications for Status Epilepticus (ESETT). N Engl J Med. 2019;381(22):2103-2113.
- Glauser T, et al. Evidence-Based Guideline: Treatment of Convulsive Status Epilepticus in Children and Adults (AES/AAN). Epilepsy Currents. 2016;16(1):48-61.
- Brophy GM, et al. Guidelines for the Evaluation and Management of Status Epilepticus (Neurocritical Care Society). Neurocrit Care. 2012;17(1):3-23.
