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Seizure Investigations

Investigations you do are always driven by specific patient parameters but an approach to what you can do is below.

Lab Investigations

  • Glucose (BSL done immediately if low give glucose IV)

  • FBC (usually transiently high post ictally, returns in hours to days, may be high in sepsis or central infection)

  • EUC (may indicate underlying precipitant, Na)

  • LFT (if indicated by known past history, ETOH ingestion, liver disease)

  • Ca (abnormalities cause seizures)

  • Urine BHcg (if indicated)

  • VBG (metabolic snapshot, useful particularly if ingestion suspected, think toxidromes)

Imaging, head CT (do you want contrast)

For any first or partial seizure or suspicion of:

  • trauma

  • malignancy

  • immunocompromise

  • anticoagulation

  • new focal neurological findings on examination

Imaging in known seizure disorder

Head CT for:

  • new focal deficits

  • trauma

  • persistent fever

  • new character or pattern to the seizures

  • suspicion for AIDS, infection

  • anticoagulation

Lumbar puncture for:

  • immunocompromise

  • persistent fever

  • severe headache

  • persistently altered mental status


  • ECG

  • EEG

  • MRI

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