Inter-observer reliability for amplitude-integrated electroencephalography in the newborn with perinatal asphyxia

Amplitude integrated electroencephalography (aEEG) is a tool widely used for neuromonitoring in the critical neonate. In the patient with perinatal asphyxia, its interpretation is key to identifying candidates for therapeutic hypothermia, detecting subclinical seizures and providing pronostic information. Our aim was to analyze the concordance in the interpretation of aEEG among neonatologists with different levels of experience.

Unicenter retrospective study of newborns ≥ 35 weeks with perinatal asphyxia included consecutively over a two-year period and monitored with aEEG for at least 6 h. The bedside neonatologist interpreted aEEG regarding background pattern, sleep-wake cycling, and seizures. The aEEG tracings were blindly reviewed by two neonatologists with different experience. The aEEG tracings were divided into periods of 0-3 h and 3-6 h of life, and the concordance (Cohen Kappa coefficient, k), between the two examiners and that of their consensus with the bedside neonatologist, was analyzed.

Seventy-five newborns were included, 5 of them were not aEEG-monitored. 132 tracings were analyzed with a very good concordance between the two examiners in the three characteristics of the aEEG. The k for the bedside neonatologist was very good for background pattern (k = 0.93), moderate (k = 0.52) for sleep-wake cycling, and weak (k = 0.32) for seizures.

This study supports that background pattern is easily interpreted compared to sleep-wake cycling or crisis, improving when targeted training on aEEG is received.