What is the approach to managing seizures in patients?

Approach to Seizure Management

For patients presenting with seizures, immediately stabilize the airway and circulation, check fingerstick glucose, and administer benzodiazepines if the seizure is ongoing or lasted >5 minutes, then rapidly identify reversible causes through targeted laboratory testing (glucose and sodium) and neuroimaging based on risk factors. 1, 2

Immediate Stabilization and Active Seizure Management

• Administer supplemental oxygen and establish IV access immediately while checking fingerstick glucose 2
• For any seizure lasting >5 minutes (status epilepticus), give lorazepam 4 mg IV at 2 mg/min as first-line treatment 3, 2
  • Alternative: diazepam 10 mg IV if lorazepam unavailable 2
• Correct hypoglycemia immediately with dextrose if glucose is low 2
• Monitor vital signs continuously including cardiac rhythm 2

Laboratory Evaluation for New-Onset Seizures

For otherwise healthy adults who have returned to baseline neurologic status:

• Obtain serum glucose and sodium levels - these are the only laboratory tests that consistently alter acute management 4, 1
• Obtain pregnancy test if patient is of childbearing age 4, 1
• Consider lumbar puncture (after head CT) in immunocompromised patients to rule out CNS infection 4, 1
• Additional tests (CBC, comprehensive metabolic panel) should only be obtained when suggested by specific clinical findings such as vomiting, diarrhea, dehydration, or known medical disorders 4, 1

Neuroimaging Decision Algorithm

Perform emergent head CT without contrast in the ED for patients with any of the following high-risk features: 4, 1

• Age >40 years
• Persistent altered mental status or focal neurologic deficits
• Recent head trauma
• History of malignancy or immunocompromised state
• Fever or persistent headache
• Anticoagulation use
• Focal seizure onset before generalization

For low-risk patients (young, returned to baseline, normal neurologic exam, reliable follow-up): deferred outpatient MRI is acceptable 4, 1

• Note: 22% of patients with normal neurologic exams still have abnormal imaging, but immediate ED imaging has not been proven to improve outcomes in low-risk patients 4, 1

Second-Line Treatment for Refractory Seizures

If seizures persist after adequate benzodiazepine administration, immediately administer valproate as the preferred second-line agent: 3, 2

• Valproate 30 mg/kg IV at 6 mg/kg/hour (88% efficacy, no hypotension risk) 3, 2
• Alternative: Levetiracetam 30 mg/kg IV at 5 mg/kg/min (73% efficacy, excellent tolerability) 3, 2
• Alternative: Fosphenytoin 20 mg PE/kg IV at 150 mg/min (84% efficacy but 12% hypotension risk) 3, 2

Valproate is superior to phenytoin/fosphenytoin because it causes no hypotension (0% vs 12%) while maintaining equivalent or better efficacy 3

Third-Line Treatment for Continued Refractory Status

If seizures persist despite benzodiazepines and second-line agents, escalate to ICU-level care with: 3, 2

• Propofol 2 mg/kg bolus, then 5 mg/kg/hour infusion (preferred - fewer ventilator days than barbiturates) 3, 2
• Alternative: Phenobarbital 20 mg/kg IV at 50-100 mg/min (effective but higher risk of hypotension and respiratory depression) 3, 2

Disposition and Admission Decisions

Emergency physicians need NOT admit patients with first unprovoked seizure who have: 4, 1

• Returned to clinical baseline in the ED
• Normal neurologic examination
• Normal or non-acute findings on investigations
• Reliable follow-up arranged

Consider admission if any of the following are present: 4, 1

• Persistent abnormal neurologic examination
• Abnormal investigation results requiring inpatient management
• Patient has not returned to baseline
• Early seizure recurrence risk factors: age >40 years, alcoholism, hyperglycemia, GCS <15 4

Seizure Recurrence Risk

Understanding early recurrence patterns is critical for disposition decisions: 4, 1

• Mean time to first seizure recurrence is 121 minutes (median 90 minutes) 4, 1
• >85% of early recurrences occur within 6 hours of ED presentation 4, 1
• Overall 24-hour recurrence rate is 19%, decreasing to 9% when alcohol-related events and focal CT lesions are excluded 4, 1
• Nonalcoholic patients with new-onset seizures have lowest recurrence (9.4%) while alcoholic patients with seizure history have highest (25.2%) 4, 1

Antiepileptic Drug Initiation

Do NOT routinely start antiepileptic drugs in the ED for single unprovoked seizures: 1

• Antiepileptic treatment reduces 1-2 year recurrence risk but does not affect long-term recurrence rates or remission rates 1
• Starting treatment for a single seizure exposes patients to medication adverse effects without proven mortality or morbidity benefit 1
• For patients with known epilepsy and single typical seizure who return to baseline, hospital admission may not be required 2

Common Pitfalls to Avoid

• Failing to identify hypoglycemia or hyponatremia as reversible causes - these require immediate correction 1
• Missing structural lesions by not performing appropriate neuroimaging in high-risk patients 1
• Using phenytoin for alcohol withdrawal seizures - phenytoin is ineffective in this setting 5
• Overlooking nonconvulsive status epilepticus in patients with persistent altered consciousness - consider emergent EEG 3
• Misdiagnosing nonepileptic events as seizures - careful history is essential as approximately 28-48% of suspected first seizures have alternative diagnoses (syncope, nonepileptic seizures, panic attacks) 4