What is the initial evaluation and management for a patient presenting with seizures?

Initial Evaluation and Management for Patients Presenting with Seizures

The initial evaluation of a patient presenting with seizures should include essential laboratory tests (serum glucose and sodium for all patients), neuroimaging (preferably MRI), and EEG within 24-48 hours, followed by prompt treatment with benzodiazepines for active seizures. 1

Diagnostic Evaluation

Laboratory Testing

Laboratory testing should be targeted based on clinical presentation:

• Essential for all patients:

  • Serum glucose
  • Serum sodium

• Additional tests based on presentation:

  • Pregnancy test for women of childbearing age
  • Complete metabolic panel for patients with altered mental status
  • Toxicology screen for altered mental status or suspected substance use
  • CBC, blood cultures, lumbar puncture if fever present
  • Antiepileptic drug levels for patients on seizure medications
  • CK levels after generalized tonic-clonic seizures
  • Troponin levels in older patients with generalized tonic-clonic seizures 1

The American College of Emergency Physicians notes that laboratory testing has low yield in otherwise healthy patients who have returned to baseline after a first-time seizure. Glucose abnormalities and hyponatremia are the most frequent abnormalities identified and are usually predicted by the history and physical examination. 2

Neuroimaging

• MRI is preferred over CT for detecting brain abnormalities in first-time seizures 1
• Neuroimaging can be avoided in patients with typical febrile seizures or primary generalized epilepsy with characteristic clinical and EEG features 1

Electroencephalography (EEG)

• Should be performed in all patients with first-time seizures
• Ideally performed within 24-48 hours of the seizure
• Helps differentiate seizure types and identify epilepsy syndromes 1
• Continuous EEG monitoring is crucial for detecting non-convulsive seizures 1

Treatment Approach

For Active Seizures

1. First-line therapy: Benzodiazepines 1
2. Second-line options (if seizures persist):
   • Levetiracetam
   • Fosphenytoin
   • Valproate 1

Medication Selection Considerations

• Levetiracetam is preferred in patients with hepatic dysfunction
• Avoid valproate and phenytoin in patients with potential hepatotoxicity 1
• Prophylactic anticonvulsant use is not recommended for patients without documented seizures 1

Status Epilepticus Management

Status epilepticus is a medical emergency requiring immediate intervention:

• Traditionally defined as seizures lasting ≥30 minutes or recurrent seizures without return to consciousness
• Some experts now define it as seizures lasting ≥5 minutes 2
• Mortality rates range from 5-22%, increasing to 65% in cases refractory to first-line therapies 2
• Transfer to ICU with continuous EEG monitoring for refractory status epilepticus 1

Discharge Criteria

Patients can be discharged if they:

• Have returned to baseline mental status
• Had a single self-limited seizure with no recurrence
• Have normal or non-acute findings on neuroimaging
• Have reliable follow-up available
• Have a responsible adult to observe them 1

Common Pitfalls to Avoid

• Delayed treatment of status epilepticus
• Inadequate benzodiazepine dosing
• Failure to monitor respiratory status
• Missing non-convulsive status epilepticus
• Overlooking treatable causes 1
• Diagnosing alcohol withdrawal seizure without excluding other causes (should be a diagnosis of exclusion) 2

Follow-up

• Referral to neurology is essential for all patients with new-onset seizures
• Neurological evaluation should include EEG, classification of seizure type, and classification of epilepsy syndrome when possible 1