Infants with severe cardiorespiratory failure treated with extracorporeal membrane oxygenation are at risk of hypoxic-ischemic injury and infarction of the brain, intracranial hemorrhage, and seizures. Consequently, this can lead to adverse neurodevelopmental outcome. We present a neonate treated with veno-arterial extracorporeal membrane oxygenation due to diaphragmatic hernia. The infant′s brain function was continuously monitored with amplitude-integrated electroencephalography. The child experienced clinical seizures and subclinical seizure discharges, detected by amplitude-integrated electroencephalography, permitting the opportunity to treat them and adjust the anticonvulsive treatment accordingly.