Status Epilepticus Management

Operational Definition (Time $t_{1}$ ): A seizure lasting > 5 minutes or recurrent seizures without return of consciousness between events. Treatment should begin immediately at this point.
Tissue Injury Threshold (Time $t_{2}$ ): A seizure lasting > 30 minutes. Risk of long-term neuronal injury and pharmacoresistance increases significantly.

Airway: Position head, suction secretions, consider intubation if GCS < 8 or airway compromised.
Breathing: High-flow oxygen (100%). Monitor SpO2 and EtCO2.
Circulation: Establish 2 large-bore IV lines. Monitor BP and ECG.
Dextrose: Bedside glucometry. If Hypoglycemia (<60 mg/dL): Give Dextrose 10% (2–5 mL/kg) or D25 (2 mL/kg).
Electrolytes: Send samples for Na+, Ca++, Mg++, AED levels, ABG, Toxicology.

Start timing the seizure.
Stabilize Airway, Breathing, Circulation.
Check Glucose. Treat hypoglycemia if present.
Attempt IV access. (Do not delay first-line treatment > 5 mins for IV access; use IO or IM/Intranasal/Buccal).

Goal: Stop seizure using Benzodiazepines.
First-Line Agent (Choose ONE):
- IV Lorazepam: 0.1 mg/kg (Max 4 mg). (Gold Standard)
- IV Diazepam: 0.2–0.3 mg/kg (Max 10 mg).
- IM Midazolam: 0.2 mg/kg (Max 10 mg). (If no IV access).
If seizure continues after 5 minutes:
- Repeat the chosen benzodiazepine dose ONCE.
- Do not exceed 2 doses (risk of respiratory depression).

Goal: Initiate long-acting anti-seizure medication (ASMs) immediately if benzodiazepines fail.
Drugs of Choice (ESETT Trial showed equal efficacy for Fosphenytoin, Valproate, Levetiracetam):
- IV Fosphenytoin: 20 mg PE/kg. (Rate: 150 mg PE/min). Preferred over Phenytoin (less hypotension/tissue necrosis).
- IV Valproate (Sodium Valproate): 20–40 mg/kg. (Rate: 3–6 mg/kg/min). Avoid in suspected metabolic/liver disease.
- IV Levetiracetam: 40–60 mg/kg (Max 4500 mg). (Infuse over 15 mins).
- IV Phenobarbital: 20 mg/kg. (Rate: 1 mg/kg/min). Consider if others unavailable or in febrile status.
Support: Monitor for hypotension and arrhythmias during infusion.

Definition: Seizure persists despite adequate Benzodiazepine + One Second-line ASM.
Action:
- Rapid Sequence Intubation (RSI) and mechanical ventilation.
- Continuous EEG monitoring (cEEG) is mandatory.
- Initiate Continuous IV Anesthetic Infusion.

Agent	Loading Dose	Maintenance Infusion	Remarks
Midazolam	0.2 mg/kg bolus	1–5 mcg/kg/min (Titrate up q15min)	Preferred in children. Less hemodynamic instability. Tachyphylaxis occurs.
Pentobarbital / Thiopental	3–5 mg/kg bolus	1–5 mg/kg/hr	Effective but causes severe hypotension/myocardial depression. Requires vasopressors.
Propofol	1–2 mg/kg bolus	1–5 mg/kg/hr	Caution: Risk of Propofol Infusion Syndrome (PRIS) in children with high doses >48hrs. Generally avoided in young children if alternatives exist.
Ketamine	1–2 mg/kg bolus	10–50 mcg/kg/min	NMDA antagonist. Neuroprotective. Good for hemodynamic stability.

Definition: SE continues > 24 hours despite anesthetics, or recurs on weaning.
Therapies:
- Ketogenic Diet (4:1 ratio via NG tube).
- Immunotherapy (IVIG, Methylprednisolone, Plasma Exchange) – Assume autoimmune/inflammatory cause (NORSE).
- Inhalational Anesthetics (Isoflurane).
- Vagus Nerve Stimulation (VNS).
- Hypothermia (Therapeutic hypothermia 32–35°C).

Drug	Dose	Max Dose	Rate
Lorazepam	0.1 mg/kg IV	4 mg	2 mg/min
Midazolam	0.2 mg/kg IM/IN/Buccal	10 mg	Bolus
Diazepam	0.2–0.3 mg/kg IV	10 mg	2 mg/min
Fosphenytoin	20 mg PE/kg IV	1500 mg PE	150 mg/min
Valproate	20–40 mg/kg IV	3000 mg	6 mg/kg/min
Levetiracetam	40–60 mg/kg IV	4500 mg	15 mins
Phenobarbital	20 mg/kg IV	1000 mg	30 mg/min

Immediate: Glucose, Electrolytes (Na, Ca, Mg), ABG.
Urgent: AED levels (if known epileptic), CBC, Renal/Liver function.
If Indicated: Neuroimaging (CT/MRI) after stabilization. Lumbar Puncture (if fever/meningeal signs present and ICP normal).