Acute neonatal encephalopathy and seizures recurrence: a combined aEEG/EEG study

Abstract

Purpose: To evaluate amplitude-integrated EEG (aEEG) in comparison with conventional (cEEG) for the identification of electrographic seizures in neonates with acute neonatal encephalopathies.

Methods: Thirty-one conventional cEEG/aEEG long-term recordings from twenty-eight newborns were reviewed in order to assess the electrographic seizure detection rate and recurrence in newborns. Two paediatric neurologists and one neonatologist, blinded to the raw full array cEEG, were asked to mark any events suspected to be an electrographic seizures on aEEG. They were asked to decide if the displayed aEEG trace showed the pattern of a single seizure (SS), repetitive seizures (RS) or status epilepticus (SE). Their ability to recognize electrographic seizures on aEEG was compared to seizures identified on full array cEEG.

Results: 25 of the 31 long-term cEEGs recordings showed electrographic seizures. The two paediatric neurologists and the neonatologist identified SE in 100% of the reviewed traces using aEEG alone while they identified 49.4% and 37.5% of electrographic seizures using aEEG alone. Overall, the correct identification ranged from 23.5% to 30.7% for SS and 66% for RS. The inter-observer agreement (k) for the identification of SE for the two paediatric neurologists and the neonatologist was 1.0. Overall the inter-observer agreement (k) for the detection of SS, RS and SE of the two paediatric neurologists was 0.91.

Conclusions: In our study the observers identified SE in 100% of the reviewed traces using raw aEEG alone, thus aEEG might represent a useful tool to detect SE in the setting of NICU. SS may not be reliably identified using aEEG alone. Simultaneous recording of the raw cEEG/aEEG provides a good level of sensitivity for the detection of neonatal electrographic seizures.

Keywords: Acute neonatal encephalopathy; Amplitude-integrated EEG; Neonatal intensive care unit; Neonatal status epilepticus; Seizures recurrence.