Pediatric emergency medicine trisk 642

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 spectroscopy) These tests require a trained pediatric neuroradiologist because of the numerous differences between the neonatal and adult brains TABLE 96.4 COMMON CAUSES OF NEONATAL SEIZURES Asphyxia-related events Metabolic derangements Cerebrovascular lesions Infection Intrapartum stress or infection Postnatal hypoxia due to trauma or systemic illness Hypoglycemia Hypocalcemia Hyponatremia/Hypernatremia Neonatal stroke Venous thrombosis Subarachnoid hemorrhage Subdural hematoma Congenital infections (e.g., toxoplasmosis, rubella, cytomegalovirus, herpes simplex virus) Viral meningitis or meningoencephalitis (e.g., herpes simplex virus, enterovirus, parvovirus) Bacterial meningitis Central nervous system malformations Dysgenetic syndromes (e.g., holoprosencephaly, lissencephaly) Chromosomal anomalies (e.g., trisomy 18) Acquired malformations Inborn errors of metabolism Nonketotic hyperglycinemia Branched-chain aminoacidopathies Urea cycle defects with hyperammonemia Adrenoleukodystrophies (e.g., Zellweger syndrome) Mitochondrial disorders with elevated lactate and pyruvate Pyridoxine deficiency Prenatal exposure to barbiturates, alcohol, heroin, cocaine, methadone may seize within days to weeks of age Drug withdrawal or intoxication Management Metabolic derangements should be managed first Hypoglycemia can be corrected by parenteral administration of a 10% dextrose solution (D10): initial administration should include a bolus of mL/kg followed by continuous dextrose infusion that can be titrated as needed to maintain euglycemia Anything equal to or greater than 25% dextrose solutions should be avoided unless there is a central line or intraosseous access or a patient is refractory to D10 boluses Hypocalcemia should be treated with parenteral infusion of calcium, most often calcium gluconate; concordant hypomagnesemia should be also corrected, as calcium levels may not normalize until serum magnesium normalizes Hyper- or hyponatremia should generally be correctly slowly to avoid sudden fluid shifts in the brain Ongoing seizures caused by hyponatremia will often stop with a simple normal saline bolus of 20 mL/kg; continued seizures due to hyponatremia refractory to standard sodium corrections may require administration of hypertonic saline (3%) at a dose of mL/kg Given the associated risks of hypertonic saline administration, 3% saline is ideally given through a central line Infants at risk for infection or meningitis should be treated with broad-spectrum antibiotics as soon as cultures are obtained The use of antiepileptics is controversial in that some believe only clinical seizures should be treated, while others that only seizures confirmed by EEG should be treated If antiepileptics are administered, the most common treatment includes phenobarbital and phenytoin/fosphenytoin Benzodiazepines are the second most common medications, but the associated sedative effects and potential for respiratory depression requires close monitoring of the infant’s cardiorespiratory status The decision to treat thrombotic cerebrovascular lesions should be made in conjunction with a pediatric hematologist Severe hyperammonemia and other metabolites due to IEM may require dialysis and should be managed in conjunction with a metabolic geneticist Pyridoxine deficiency may respond to parenteral administration of pyridoxine, but requires continuous EEG monitoring to assess effectiveness Neonatal Encephalopathy Goals of Treatment The primary goal of treatment is to identify the encephalopathic newborn, and provide supportive care while determining the etiology of encephalopathy Infants with encephalopathy due to asphyxial events may present in multisystem organ failure as well autonomic instability secondary to brain injury In this instance, goals of treatment include cardiorespiratory stabilization, particularly if there are signs of autonomic dysfunction, and maintaining thermoneutral environment, ...spectroscopy) These tests require a trained pediatric neuroradiologist because of the numerous differences between the neonatal and adult brains... status The decision to treat thrombotic cerebrovascular lesions should be made in conjunction with a pediatric hematologist Severe hyperammonemia and other metabolites due to IEM may require dialysis