What is the management of a seizure in an emergency setting?

Management of Seizures in Emergency Settings

In emergency settings, intravenous benzodiazepines are the first-line treatment for active seizures, followed by second-line agents such as levetiracetam, fosphenytoin, or valproate if seizures persist. 1

Initial Assessment and Stabilization

• Ensure patent airway, adequate oxygenation, and circulatory support before administering anticonvulsant medications 2, 1
• Rapidly assess for and address potential underlying causes of seizures, including hypoglycemia, hyponatremia, hypoxia, drug toxicity, CNS infection, stroke, or hemorrhage 1, 3
• Classify the seizure as provoked (occurring within 7 days of an acute neurologic, systemic, metabolic, or toxic insult) or unprovoked (occurring without acute precipitating factors) to guide management 2

First-Line Treatment

• Administer intravenous benzodiazepines as first-line therapy for active seizures 2, 1:
  • Lorazepam: 4 mg IV slowly (2 mg/min) for adults; may repeat once after 10-15 minutes if seizures continue 4
  • Diazepam: 5-10 mg IV at a rate not exceeding 5 mg/min; may repeat every 10-15 minutes up to maximum 30 mg 5
  • Midazolam: 10 mg IM is an effective alternative when IV access is challenging 2

Second-Line Treatment for Persistent Seizures

If seizures persist despite optimal benzodiazepine dosing, administer one of the following second-line agents (all have similar efficacy) 2, 1:

• Levetiracetam: 30-50 mg/kg IV at 100 mg/min (maximum 4500 mg)

  • Advantages: Favorable side effect profile, fewer drug interactions 1, 6
  • Disadvantages: May cause nausea and rash 1
  • Safety: Lowest rate of life-threatening hypotension (0.7%) 1, 6

• Fosphenytoin: 18-20 PE/kg IV at maximum rate of 150 PE/min

  • Advantages: Can be administered IM if needed 1
  • Disadvantages: Risk of hypotension (3.2%) and cardiac dysrhythmias 1, 6, 7
  • Requires cardiac monitoring during administration 7

• Valproate: 20-30 mg/kg IV at maximum rate of 10 mg/kg/min

  • Advantages: Rapid administration, minimal cardiorespiratory effects 1
  • Disadvantages: Contraindicated in liver disease, risk of thrombocytopenia 1
  • Safety: Intermediate rate of life-threatening hypotension (1.6%) 1, 6

Management of Status Epilepticus

Status epilepticus is defined as seizures lasting longer than 5 minutes or multiple seizures without return to neurologic baseline 2:

• Begin with benzodiazepines as described above 2, 1
• If seizures continue after optimal benzodiazepine dosing, administer one of the second-line agents 2, 1
• According to the ESETT trial (Class I evidence), levetiracetam, fosphenytoin, and valproate have similar efficacy for terminating status epilepticus (approximately 45-47% success rate) 1
• For refractory status epilepticus (continuing after second-line therapy), consider:
  • Combination therapy with multiple agents 6
  • Addition of propofol or barbiturates if the patient is intubated 6

Special Considerations

• Monitor for respiratory depression with benzodiazepines, especially in elderly patients or those with respiratory compromise 4, 5
• Phenytoin is ineffective for seizures secondary to alcohol withdrawal, theophylline toxicity, or isoniazid toxicity 3
• Consider non-convulsive status epilepticus in patients with unexplained altered mental status 1, 3
• For patients with known seizure disorder who have returned to baseline after a seizure, there is insufficient evidence to support routine loading with antiseizure medication in the ED 6

Monitoring and Follow-up

• Monitor vital signs, oxygen saturation, and level of consciousness throughout treatment 2, 1
• For patients receiving phenytoin/fosphenytoin, monitor for cardiac arrhythmias and hypotension 7
• For patients receiving valproate, monitor for thrombocytopenia and liver toxicity 6
• For patients receiving levetiracetam, monitor for behavioral issues 6
• Consider EEG monitoring if concerned about non-convulsive status epilepticus 1