EAGLET: EEG vs aEEG to Improve the Diagnosis of neonataL Seizures and Epilepsy (EAGLET)

The EAGLET Project: EEG vs aEEG to Improve the Diagnosis of neonataL Seizures and Epilepsy - a Randomised Trial

Norfolk and Norwich University Hospitals NHS Foundation Trust, Luton and Dunstable Hospital NHS Foundation Trust, Infant, University College Cork, Ireland, Guy's and St Thomas' NHS Foundation Trust, University Hospital Southampton NHS Foundation Trust

The current project undertakes a prospective multicentre randomised controlled trial to evaluate whether full or continuous electroencephalography (cEEG) is superior to amplitude-integrated electroencephalography (aEEG) in the real time evaluation and diagnosis of neonatal seizures and in reducing time to treatment. At-risk new-born infants will be recruited on the participating neonatal intensive care units (NICUs) by trained specialist staff and will have 24 hours of EEG monitoring.

Seizures are the most common neurological emergency in the neonatal period, affecting over 2000 infants per year in the UK. Although neonatal seizures usually result from acute brain insults, about 10-15% represent genetic forms of epilepsy which are often diagnosed late, thus limiting the timely use of targeted therapies. Lack or delayed initiation of treatment results in a high seizure burden which is independently associated with worse clinical outcomes. Diagnosing neonatal seizures is challenging because most have only subtle or no clinical manifestation. The gold standard for seizure detection is continuous electroencephalography (cEEG). cEEG can assist with establish the aetiology of seizures, and their management. However, this capability is lacking in most neonatal intensive care units (NICU) due to lack of on-site specialist support. The more common amplitude-integrated EEG (aEEG) uses a limited number of electrodes and is easier to apply and interpret but has been shown to miss a significant number of seizures. It is unclear how often seizure treatment is missed or delayed due to lack of cEEG access. Although studies have compared the diagnostic value of aEEG and cEEG retrospectively, the measured sensitivity of aEEG ranges widely (25-85%), likely due to poor design (retrospective, lack of adequate control group, no power calculations). The current project undertakes a prospective multicentre randomised controlled trial to evaluate whether cEEG is superior to aEEG in the real time evaluation and diagnosis of neonatal seizures and in reducing time to treatment. At-risk neonates will be recruited on the NICU by trained specialist staff and will have 24 hours of EEG monitoring.

In group B, the standart-care equivalent aEEG review is undertaken by NICU staff via a 2-channel display. In addition to the standard care, concurrent full EEG is reviewed remotely with regular feedback by a specialist trained clinical neurophysiologist. The clinical neurophysiology reports only on seizure burden, no information or direction is provided regarding clinical management.

The primary outcome measure for the study is the difference in the number of correctly identified seizures by NICU staff in real time with (full EEG) or without (aEEG only) the support of clinical neurophysiology.

Each participant's seizure burden, treatment and discharge timelines will be recorded up until their discharge from the hospital, or for up to 6 months, whichever came first.

Parents may fill in the questionnaire online after their infant's discharge from hospital, the questionnaire will take a maximum of 10 minutes to complete.

Inclusion Criteria: Term or preterm neonate, born at post-menstrual age (PMA) 32-44 weeks; And at least one of the following: (2.1) Neonate with any clinical event suspicious of seizures (2.2) Neonate at high-risk of seizures with confirmed or suspected: (2.2.1) Hypoxic ischaemic encephalopathy (moderate to severe, or deemed eligible for therapeutic hypothermia) (2.2.2) Cerebral vascular insult (e.g., perinatal arterial ischaemic stroke, cerebral venous sinus thrombus) (2.2.3) Meningitis / encephalitis - Inflammatory (2.2.4) Inborn error of metabolism (2.2.5) Brain malformation (2.2.6) Large intraventricular haemorrhage (III-IV) Infant is up to 28 days of age Written informed parental consent can be obtained. Exclusion Criteria: No parental consent Poor prognosis of immediate survival Any contraindication to perform EEG (e.g. structural pathologies interfering with EEG electrode placement, such as cephalohematoma or subgaleal haemorrhage). Infants born at less than 31+6 weeks PMA and infants who are or are suspected to be experiencing or are at high-risk of seizures when aged 29 days or older.

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