What is the recommended emergency department approach for managing generalized tonic‑clonic seizures or status epilepticus in a primary‑care hospital, including initial assessment and first‑line and second‑line treatment for pediatric and adult patients?

Emergency Department Approach to Seizures: Pediatric vs Adult Management

Benzodiazepines are first-line treatment for both pediatric and adult patients with generalized tonic-clonic seizures or status epilepticus, followed by immediate escalation to second-line agents if seizures persist beyond 5 minutes, with key differences in dosing, administration rates, and drug selection between age groups. 1

Initial Assessment & Stabilization (0-5 minutes)

Both pediatric and adult patients require:

• Immediate assessment of airway, breathing, and circulation with high-flow oxygen 2
• Fingerstick glucose check and correction of hypoglycemia 1
• Establishment of IV access with simultaneous fluid resuscitation 1
• Airway equipment immediately available before any benzodiazepine administration due to respiratory depression risk 1, 3
• Continuous vital sign monitoring, particularly oxygen saturation and blood pressure 1, 2

Simultaneously search for reversible causes: hypoglycemia, hyponatremia, hypoxia, drug toxicity or withdrawal, CNS infection, stroke, intracerebral hemorrhage 1, 2

First-Line Treatment: Benzodiazepines

Adult Dosing

Lorazepam 4 mg IV at 2 mg/min is the preferred first-line agent, with 65% efficacy in terminating status epilepticus and superior efficacy over diazepam (59.1% vs 42.6%) 1, 3

• May repeat once after 10-15 minutes if seizures continue 1, 3
• Lorazepam preferred due to longer duration of action compared to other benzodiazepines 1

Pediatric Dosing

Lorazepam 0.1 mg/kg IV (maximum 2 mg) for convulsive status epilepticus 1, 2

• May repeat once after at least 1 minute 1
• For non-convulsive status epilepticus: 0.05 mg/kg IV (maximum 1 mg), may repeat every 5 minutes up to maximum 4 doses 1

Alternative Routes When IV Access Unavailable

• IM midazolam 0.2 mg/kg (maximum 6 mg) for both adults and children, may repeat every 10-15 minutes 1, 4
• Intranasal midazolam with onset of action within 1-2 minutes 1
• Rectal diazepam 0.5 mg/kg if buccal/intranasal routes not feasible 1

Critical pitfall: Never use IM diazepam due to erratic absorption—use rectal route instead 1

Second-Line Treatment (5-20 minutes)

If seizures persist after adequate benzodiazepine dosing, immediately escalate to one of the following agents—do not delay beyond 5-10 minutes: 1, 2

Adult Second-Line Options (in order of safety profile)

1. Valproate 20-30 mg/kg IV (maximum 3000 mg) over 5-20 minutes

• 88% efficacy with 0% hypotension risk 1, 2
• Superior safety profile compared to phenytoin 1
• Absolute contraindication in women of childbearing potential due to teratogenic risk 1

2. Levetiracetam 30 mg/kg IV (maximum 2500-3000 mg) over 5 minutes

• 68-73% efficacy with minimal cardiovascular effects 1, 2
• No cardiac monitoring required 1
• Approximately 0.7% hypotension risk 1

3. Fosphenytoin 20 mg PE/kg IV at maximum rate of 150 PE/min

• 84% efficacy but 12% hypotension risk 1, 2, 5
• Requires continuous ECG and blood pressure monitoring 1, 5
• Traditional and most widely available option 1

4. Phenobarbital 20 mg/kg IV over 10 minutes

• 58.2% efficacy as initial second-line agent 1
• Higher risk of respiratory depression and hypotension 1, 2

Pediatric Second-Line Options

Key difference: Maximum infusion rates are weight-based and slower than adults 1, 5

1. Valproate 20-30 mg/kg IV over 5-20 minutes

• Pediatric data shows 90% seizure termination vs 77% with phenobarbital, with significantly fewer adverse effects (24% vs 74%) 1

2. Levetiracetam 40 mg/kg IV (maximum 2500 mg) over 5-15 minutes

• Higher loading dose than adults 1

3. Fosphenytoin 20 mg PE/kg IV

• Maximum rate: 2 mg PE/kg/min OR 150 mg PE/min, whichever is slower 1, 5
• This is the critical pediatric difference—rate must not exceed 1-3 mg/kg/min 1

4. Phenobarbital 20 mg/kg IV over 10 minutes (maximum 1000 mg)

• May be preferred in very young children 1

Refractory Status Epilepticus (20+ minutes)

Definition: Seizures continuing despite benzodiazepines and one second-line agent 1

Initiate continuous EEG monitoring at this stage—25% of patients with apparent seizure cessation have continuing electrical seizures 1, 2

Third-Line Anesthetic Agents (Both Pediatric & Adult)

1. Midazolam continuous infusion (first choice)

• Loading: 0.15-0.20 mg/kg IV 1, 4
• Maintenance: 1 mg/kg/min, titrate up by 1 mg/kg/min every 15 minutes to maximum 5 mg/kg/min 1
• 80% efficacy with 30% hypotension risk 1
• Before tapering midazolam, load with a long-acting anticonvulsant (phenytoin/fosphenytoin, valproate, levetiracetam, or phenobarbital) 1

2. Propofol

• Loading: 2 mg/kg bolus 1, 4
• Maintenance: 3-7 mg/kg/hour infusion 1
• 73% efficacy with 42% hypotension risk 1
• Requires mechanical ventilation but shorter duration than barbiturates (4 days vs 14 days) 1

3. Pentobarbital (highest efficacy but most adverse effects)

• Loading: 13 mg/kg 1, 4
• Maintenance: 2-3 mg/kg/hour 1
• 92% efficacy but 77% hypotension risk requiring vasopressors 1
• Mean 14 days mechanical ventilation 1

All anesthetic agents require:

• Mechanical ventilation readiness 1, 4
• Continuous blood pressure monitoring with vasopressors available 1
• Continuous EEG monitoring to guide titration 1

Maintenance Dosing After Seizure Control

Adult Maintenance

• Levetiracetam: 30 mg/kg IV every 12 hours OR increase to 20 mg/kg every 12 hours (maximum 1500 mg) for convulsive SE 1
• Valproate: Continue at maintenance doses based on clinical response 1
• Phenobarbital: 1-3 mg/kg IV every 12 hours if used 1, 2

Pediatric Maintenance

• Levetiracetam: 30 mg/kg IV every 12 hours (maximum 1500 mg) for convulsive SE; 15 mg/kg every 12 hours for non-convulsive SE 1
• Phenobarbital: 1-3 mg/kg IV every 12 hours 1
• Lorazepam: 0.05 mg/kg (maximum 1 mg) IV every 8 hours for 3 doses 2

Critical Pitfalls to Avoid

1. Dosing errors with fosphenytoin: Do not confuse PE (phenytoin equivalents) with actual drug concentration in vial 1, 5

2. Excessive infusion rates in pediatrics: Fosphenytoin rate must not exceed 2 mg PE/kg/min in children vs 150 mg PE/min in adults 1, 5

3. Delaying second-line agents: Move to next treatment step if seizures continue after 5-10 minutes 2

4. Using neuromuscular blockers alone: They only mask motor manifestations while allowing continued electrical seizure activity and brain injury 1

5. Skipping to third-line agents: Do not use pentobarbital or propofol until benzodiazepines and a second-line agent have been tried 1

6. Failure to monitor for respiratory depression: Especially critical with benzodiazepines and barbiturates in both age groups 2

7. Assuming seizures have stopped clinically: Obtain EEG if patient does not awaken within expected timeframe—nonconvulsive status epilepticus occurs in >50% of refractory cases 1

Key Pediatric vs Adult Differences Summary

Parameter	Adult	Pediatric
Lorazepam dose	4 mg IV	0.1 mg/kg (max 2 mg)
Levetiracetam loading	30 mg/kg	40 mg/kg
Fosphenytoin max rate	150 mg PE/min	2 mg PE/kg/min OR 150 mg PE/min (whichever slower)
Valproate efficacy	88%	90%
Preferred second-line	Valproate or levetiracetam	Valproate (superior pediatric data)

Mortality for status epilepticus ranges from 5-22% overall, reaching 65% in refractory cases, making aggressive time-based treatment essential. 1