Seizure Management in the Emergency Department

Initial Evaluation and Laboratory Tests

For an ER patient presenting with new onset seizures and persistent headaches, essential laboratory tests should include serum glucose, electrolytes (especially sodium), complete blood count, calcium, renal function tests, and a toxicology screen, as recommended by the American College of Emergency Physicians [1]
Blood glucose testing is crucial to identify hypoglycemia, a critical reversible cause of seizures [1]
Serum electrolytes, particularly sodium levels, should be evaluated as hyponatremia is a common metabolic abnormality associated with seizures [1]
A complete blood count (CBC) is necessary to evaluate for infection or other systemic conditions [1]
Calcium levels should be checked to rule out hypocalcemia as a potential seizure trigger [1]
Renal function tests, including BUN and creatinine, should be assessed to evaluate kidney function [1]
A toxicology screen is particularly important if the patient's history suggests possible substance use [1]
Magnesium levels should be considered in patients with malnutrition, alcoholism, or certain medications [1]
A pregnancy test should be performed for women of childbearing age, as pregnancy can affect seizure threshold and treatment decisions [1]

Several prospective studies demonstrate the relatively low yield of routine laboratory testing in otherwise healthy patients with new-onset seizures who have returned to baseline mental status, with only a few cases of unexpected hypoglycemia identified [1]
A study of 163 patients found only one unexpected case of hypoglycemia [1]
A study of 136 patients found only two cases of unpredicted hypoglycemia [1]
A study of 247 patients identified only one case of unsuspected hypoglycemia [1]

A lumbar puncture should be considered if there are signs of meningeal irritation, fever, or if subarachnoid hemorrhage is suspected after normal CT imaging, as recommended by the American College of Radiology [2]
Inflammatory markers, such as ESR/CRP, should be evaluated if temporal arteritis or other inflammatory conditions are suspected [2]

History and physical examination remain crucial and will predict most laboratory abnormalities, and should not be relied upon solely [1]
Glucose abnormalities and electrolyte disturbances are the most common reversible metabolic causes of seizures, and should not be missed [1]
Persistent headaches should not be overlooked, as patients with focal neurological findings, persistent headache, and recent history of head trauma have a higher probability of structural abnormalities requiring imaging [2]