monitoring, as these medications can quiet clinical seizures despite ongoing electrical seizures Clinical Considerations Clinical Recognition Clinical seizures can be focal clonic, multifocal or migratory clonic, tonic, myoclonic, or subtle The most common is the subtle seizure, often presenting with repetitive tongue or lip-smacking movements, eye deviations, or unusual bicycling or peddling movements These movements may be associated with autonomic dysfunction, such as changes in heart rate, blood pressure, or oxygenation The converse, autonomic disturbances such as apnea or bradycardia without associated movement anomalies rarely reflect seizure activity Triage Considerations Neonates with suspected seizures should be triaged urgently as prolonged seizures can cause permanent brain injury or progress to systemic cardiorespiratory compromise Clinical Assessment Often, parents will present to the ED with videos of repetitive behaviors believed to be seizures These videos can be very helpful Common causes of seizures are summarized in Table 96.4 Detailed history can suggest recent asphyxial events or trauma Prenatal history can identify the neonate at risk for withdrawal syndromes, and serum or urine toxicology screens can identify acute intoxication STAT bedside glucose and sodium testing should be performed Serum evaluation should include glucose and electrolytes (including magnesium, calcium, and phosphorus) Ammonia, lactate, and pyruvate can identify metabolic derangements as well as suggest certain IEM Serum blood gas evaluation may identify recent hypoxic–ischemic injury Cultures and viral testing of the blood, urine, and CSF can identify infection CNS imaging may include head US, CT, or MRI Head US can be done through the anterior fontanelle, and can help identify ventriculomegaly or intraventricular hemorrhage, but could also suggest cerebral edema when the lateral ventricles are small Head CT is the test of choice when there is a concern for trauma or cerebrovascular lesions This does expose the neonate to radiation and so should only be used when there is high suspicion of these lesions Brain MRI can identify CNS malformations, abscesses or empyemas (with the use of gadolinium), asphyxial events (particularly with the use of diffusion-weighted sequences), certain metabolic derangements and IEM (with magnetic resonance