What is the appropriate acute treatment and subsequent management for a patient presenting with a seizure?

Acute Seizure Management

Administer intravenous lorazepam 4 mg at 2 mg/min immediately for any actively seizing patient—this is your definitive first-line treatment with 65% efficacy in terminating status epilepticus. 1

Immediate Actions (0-5 Minutes)

First-Line Benzodiazepine Therapy

• Give IV lorazepam 4 mg at 2 mg/min as soon as IV access is secured—lorazepam is superior to diazepam (59.1% vs 42.6% seizure cessation) and has longer duration of action 1
• Have airway equipment immediately available before administering any benzodiazepine, as respiratory depression can occur 1, 2
• Check fingerstick glucose immediately and correct hypoglycemia while administering treatment—this is a rapidly reversible cause 1
• Time the seizure duration—status epilepticus is operationally defined as seizures lasting ≥5 minutes, requiring immediate escalation 1, 3

Alternative Routes When IV Access Delayed

• IM midazolam if IV access is challenging—shows 97% relative efficacy compared to IV diazepam 1
• Intranasal midazolam with onset within 1-2 minutes and peak effect at 3-4 minutes 1
• Rectal diazepam 0.5 mg/kg if buccal/intranasal routes not feasible 1

Second-Line Treatment (5-20 Minutes After Benzodiazepines)

If seizures persist after adequate benzodiazepine dosing, immediately escalate to one of the following second-line agents—all three have equivalent efficacy (45-47%), so choose based on safety profile and contraindications. 1

Recommended Second-Line Agents (Listed by Safety Profile)

Valproate is the safest option with superior efficacy:

• Dose: 40 mg/kg IV (maximum 3000 mg) over 10 minutes 1
• Efficacy: 88% seizure cessation with 0% hypotension risk 1
• Intubation rate: 16.8% 1
• Absolute contraindication: Women of childbearing potential due to fetal teratogenicity 1

Levetiracetam has minimal cardiovascular effects:

• Dose: 60 mg/kg IV (maximum 4500 mg) over 10 minutes 1
• Efficacy: 68-73% seizure cessation 1
• Hypotension risk: 0.7%, intubation rate: 20% 1
• No cardiac monitoring required 1

Fosphenytoin requires continuous monitoring:

• Dose: 20 mg PE/kg IV at maximum rate of 150 mg/min 1
• Efficacy: 84% but hypotension risk 3.2% 1
• Intubation rate: 26.4% 1
• Requires continuous ECG and blood pressure monitoring 1

Phenobarbital has highest respiratory depression risk:

• Dose: 20 mg/kg IV over 10 minutes 1
• Efficacy: 58.2% as initial second-line agent 1
• Higher risk of respiratory depression and hypotension 1

Third-Line Treatment for Refractory Status Epilepticus (20+ Minutes)

Refractory status epilepticus is defined as seizures continuing despite benzodiazepines and one second-line agent—initiate continuous EEG monitoring at this stage. 1

Anesthetic Agents (Choose Based on Clinical Context)

Midazolam infusion (preferred for most patients):

• Loading dose: 0.15-0.20 mg/kg IV 1
• Continuous infusion: 1 mg/kg/min, titrate up by 1 mg/kg/min every 15 minutes to maximum 5 mg/kg/min 1
• Efficacy: 80% with 30% hypotension risk 1
• Load with phenytoin/fosphenytoin, valproate, levetiracetam, or phenobarbital during infusion before tapering 1

Propofol (for intubated patients):

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

Pentobarbital (highest efficacy but most complications):

• Loading dose: 13 mg/kg 1
• Continuous infusion: 2-3 mg/kg/hour 1
• Efficacy: 92% but 77% hypotension risk requiring vasopressors 1
• Prolonged mechanical ventilation (mean 14 days) 1

Critical Simultaneous Actions Throughout Treatment

Search for and treat underlying causes while administering anticonvulsants—do not delay treatment for imaging: 1, 3

• Hypoglycemia—check fingerstick glucose immediately 1
• Hyponatremia—most common electrolyte disturbance precipitating seizures 1
• Hypoxia—ensure adequate oxygenation 1
• Drug toxicity or withdrawal syndromes (especially alcohol, benzodiazepines) 1
• CNS infection—consider if fever present 1
• Acute stroke or intracerebral hemorrhage—especially in patients >40 years 1

Obtain neuroimaging (CT head) after seizure control is achieved—do not delay anticonvulsant administration for imaging 1

Monitoring Requirements

• Continuous vital sign monitoring is essential, particularly respiratory status and blood pressure 1
• Continuous EEG monitoring for refractory cases to detect non-convulsive seizure activity and guide therapy 1
• Maintain NPO status until swallowing ability is assessed to prevent aspiration 3
• Monitor for at least 24-48 hours after anesthetic discontinuation as breakthrough seizures occur in >50% of patients 1

Management After First Unprovoked Seizure (Once Seizure Controlled)

Emergency physicians need not initiate antiepileptic medication in the ED for patients who have had an unprovoked seizure without evidence of brain disease or injury. 4

When NOT to Start Antiepileptic Drugs in ED:

• Provoked seizure—identify and treat precipitating medical conditions 4
• First unprovoked seizure without brain disease/injury—approximately one-third will have recurrence within 5 years, but outpatient initiation is appropriate 4

When to CONSIDER Starting Antiepileptic Drugs:

• First unprovoked seizure with remote history of brain disease or injury (stroke, trauma, tumor)—may initiate in ED or defer in coordination with other providers 4
• Two or more unprovoked seizures—recurrence risk increases to 75% within 5 years 4

Disposition:

• Patients who have returned to clinical baseline can be safely discharged without admission 4, 1
• Arrange outpatient neurology follow-up and EEG 1

Prognosis

• Overall mortality from status epilepticus: 5-22% 1
• Refractory status epilepticus mortality: up to 65% 1
• Intubation required in 16-26% of status epilepticus cases 1

Common Pitfalls to Avoid

• Do not use neuromuscular blockers alone (e.g., rocuronium)—they only mask motor manifestations while allowing continued electrical seizure activity and brain injury 1
• Do not skip to third-line agents until benzodiazepines and a second-line agent have been tried 1
• Do not delay anticonvulsant administration for neuroimaging in active status epilepticus 1
• Do not attribute altered mental status solely to post-ictal state—obtain urgent EEG if patient does not awaken within expected timeframe, as non-convulsive status epilepticus occurs in >50% of cases 1