Neonatal Seizures: EEG and Anticonvulsant Selection

Neonatal seizures are a neurological emergency, but they are also a diagnostic challenge. Movements such as jitteriness, tremors, apnea, eye deviation, and autonomic instability may resemble epileptic events, while many genuine seizures have no obvious clinical expression. A structured approach therefore depends on rapid stabilization, continuous electroencephalography, and treatment directed at the underlying cause.

Electroencephalography (EEG) helps distinguish electrographic seizures from non-epileptic movements, identifies seizure burden, and reveals whether antiseizure medication is suppressing clinical behavior without stopping abnormal cortical activity. Anticonvulsant selection must then account for gestational age, organ function, etiology, cardiac risk, therapeutic hypothermia, and the infant’s evolving neurological examination.

The principles discussed here are intended for neonatal intensive care teams and should be applied through local protocols, specialist consultation, and careful review of each infant’s clinical context. Management should proceed alongside evaluation for hypoglycemia, electrolyte disturbance, infection, stroke, hemorrhage, hypoxic-ischemic injury, and metabolic disease.

Recognizing Seizures In The Newborn

Neonatal seizures may be clonic, tonic, myoclonic, or subtle. Clonic seizures often involve rhythmic jerking of one limb or one side of the face, whereas tonic events may produce sustained extension or flexion. Autonomic changes, including oxygen desaturation, heart-rate variation, or blood-pressure fluctuation, can accompany seizures but are not diagnostic on their own.

Some abnormal movements are more likely to be nonepileptic. Jitteriness commonly stops when the affected limb is held, while clonic seizures usually continue despite gentle restraint. Benign neonatal sleep myoclonus occurs during sleep and does not produce a corresponding ictal EEG pattern. Apnea, lip smacking, bicycling movements, and eye deviation require particular caution because they may be subtle manifestations of cortical seizures.

The first response is stabilization rather than immediate medication. The team should assess airway and breathing, obtain a bedside glucose measurement, correct severe hypoglycemia, evaluate temperature and perfusion, and consider urgent treatment for suspected infection. Blood gas analysis, calcium, magnesium, sodium, renal and hepatic function, cultures, and neuroimaging are selected according to the presentation and local practice.

Why Continuous EEG Matters

A standard short EEG can identify background abnormalities and interictal discharges, but it may miss seizures that occur outside the recording period. Continuous video-EEG is more useful when seizures are suspected, particularly in critically ill infants, those with hypoxic-ischemic encephalopathy, and babies receiving antiseizure medication. It also allows clinicians to correlate movements with electrical activity.

Electroclinical dissociation is common after treatment. Phenobarbital or another medication may stop visible jerking while electrographic seizures continue. For this reason, clinical observation alone is an unreliable measure of response. A seizure burden that remains high can contribute to secondary brain injury and should prompt reassessment of the diagnosis, treatment, and underlying cause.

Amplitude-integrated EEG can support bedside surveillance where full video-EEG is not immediately available. However, it has lower sensitivity for brief, focal, low-amplitude, or artifact-obscured events. An abnormal tracing should be reviewed with conventional EEG whenever possible, and a normal-appearing aEEG should not overrule strong clinical concern. Monitoring duration is individualized, but continued recording after the last electrographic seizure is commonly used to detect recurrence.

Matching Antiseizure Drugs To The Clinical Setting

Medication is generally considered when electrographic seizures are recurrent, prolonged, or associated with a significant acute brain insult. Correcting an underlying metabolic or infectious cause remains essential; antiseizure therapy does not replace glucose correction, antimicrobial treatment, management of hypocalcemia, or treatment of structural disease.

Phenobarbital remains a widely used first-line agent for many acute symptomatic neonatal seizures, particularly when rapid seizure control is needed. Its limitations include respiratory depression, hypotension, sedation, and incomplete efficacy. It can also make neurological assessment more difficult. Dose selection and additional loading should follow a neonatal protocol with cardiorespiratory monitoring.

Levetiracetam is often selected because it has relatively limited respiratory and cardiovascular effects and is available intravenously in many settings. Evidence for first-line use is growing, although response rates and long-term comparative data remain less established than clinicians would prefer. Fosphenytoin or phenytoin may be useful for focal seizures or seizures resistant to phenobarbital, but electrocardiographic monitoring is required because of potential arrhythmia and hypotension.

Adapting Treatment To Etiology And Temperature

The cause of the seizure influences both urgency and drug selection. Hypoxic-ischemic encephalopathy may present with early electrographic seizures, while arterial ischemic stroke, cerebral venous thrombosis, intracranial hemorrhage, meningitis, and congenital infection require targeted diagnostic pathways. Seizures associated with hypoglycemia, hypocalcemia, or sodium imbalance may resolve after correction, although EEG surveillance is still important.

Infants receiving therapeutic hypothermia need especially careful monitoring. Cooling can alter drug distribution, hepatic metabolism, renal clearance, and cardiovascular tolerance. Seizure frequency may change during rewarming, and the EEG background may provide valuable prognostic information. Guidance on therapeutic hypothermia should be integrated with the neonatal seizure protocol rather than treating the neurological and temperature-management plans as separate tasks.

Jaundice also belongs in the differential diagnosis. Severe unconjugated hyperbilirubinemia can cause acute bilirubin encephalopathy, with abnormal tone, lethargy, poor feeding, and, in advanced cases, seizures. Prompt bilirubin assessment and evidence-based phototherapy protocols are part of prevention, while suspected bilirubin neurotoxicity may require escalation beyond routine phototherapy.

Monitoring Response And Deciding When To Stop

The immediate goal is electrographic seizure control with the fewest adverse effects. Clinicians should document the time of treatment, loading dose, seizure duration, EEG response, cardiorespiratory changes, and subsequent recurrence. If seizures persist, the team should confirm that the events are epileptic, check medication delivery and dosing, reconsider the cause, and assess for disorders such as pyridoxine-dependent epilepsy or other inborn errors of metabolism.

The need for maintenance treatment after an acute symptomatic seizure is not automatic. If the infant has a normalizing examination, improving EEG background, no ongoing electrographic seizures, and a clearly resolved provoking condition, prolonged medication exposure may offer limited benefit. Conversely, persistent seizures, markedly abnormal background activity, structural brain injury, or an epilepsy syndrome may justify continued therapy and specialist follow-up.

Discharge planning should include a clear medication schedule, adverse-effect warnings, rescue guidance when appropriate, and a defined neurology appointment. Parents need to know how seizures may appear without dramatic shaking and why medication should not be stopped abruptly. The emotional burden can be substantial, so coordinated perinatal mental health screening may help identify anxiety, depression, sleep disruption, and difficulty coping after a frightening neonatal admission.

A Practical Bedside Framework

A reliable workflow reduces delays and limits treatment based solely on uncertain clinical movements. The team should assign responsibility for EEG review, medication preparation, airway monitoring, laboratory investigation, and family communication. Every suspected event should be described precisely, recorded when feasible, and matched against the EEG tracing.

Useful bedside priorities include:

• Stabilize breathing, circulation, temperature, and glucose before or alongside seizure treatment.
• Start continuous video-EEG promptly when seizures are suspected or the infant is at high risk.
• Treat electrographic seizures, not only visible movements, and reassess after every loading dose.
• Choose medication according to etiology, hemodynamic status, renal and hepatic function, and concurrent cooling.
• Reconsider the diagnosis when seizures are refractory, unusually patterned, or unexplained by the initial evaluation.

The neurological examination, EEG background, seizure burden, imaging, laboratory results, and clinical course should be interpreted together. No single tracing or medication response can predict outcome for every newborn. Early specialist involvement is particularly important when seizures continue despite first- and second-line treatment, when there is a major structural lesion, or when an inherited metabolic disorder is possible.

A coordinated protocol linking neonatal nurses, neonatologists, neurologists, pharmacists, EEG technologists, and families can improve recognition and reduce avoidable treatment delays. Clinical teams should review their seizure pathway regularly, audit EEG availability and response times, and update drug dosing according to current neonatal evidence and local safety standards.

Implement these principles through your neonatal unit’s emergency algorithm, continuous EEG pathway, and medication-monitoring policy. Prompt recognition, cause-directed care, and close neurological follow-up give affected infants the best opportunity for seizure control and informed long-term support.