-Seizures are the most frequent neurological event in newborns and clinical data suggest that etiology is the dominant factor in long term outcome. However, there are consistent background EEG abnormalities associated to neonatal seizures that are usually related to unfavorable outcome as the burst -suppression pattern. Objective: The objective of this study was to correlate clinical and EEG features associated to long -term outcome of newborns with non -reactive burst -suppression (BS) EEG. Method: Newborns included in the study were selected from our database and had conceptional age (at the time of first EEG) >37 weeks, EEG recordings with non -reactive BS available for review and clinical follow up. Results: 12 newborns met inclusion criteria, 50% had seizures in the first day of life. Seizures became refractory to treatment in all of them. In 50% the etiology of seizures was considered cryptogenic, 33% had inborn errors of metabolism and 17% had clinical history and neuroimage suggestive of hypoxic-ischemic encephalopathy. The follow-up showed that 7/12 infants deceased, 3 during the first year of life, and one in the neonatal period. All the survivors had severe developmental delay and multifocal neurological impairment. 92% developed refractory epilepsy, 58% were latter diagnosed with West syndrome. Conclusion: The non-reactive BS pattern may appear related to many neonatal neurological disorders and is associated with early and refractory neonatal seizures. It is clearly associated with elevated morbidity and mortality and to the development of post-neonatal epilepsy.KEY WORDS: neonatal EEG, neonatal seizures, burst-suppression pattern, neonatal epileptic syndromes.Valor prognóstico do EEG com padrão de surto-supressão não reativo associado a convulsões neonatais precoces RESUMO -Convulsões representam o evento neurológico mais freqüente no período neonatal e a etiologia das crises parece ser o aspecto clínico mais associado ao prognóstico a longo prazo. Entretanto, existem padrões anormais de EEG, que de forma consistente relacionam-se a prognóstico, entre eles o padrão de surto -supressão. Objetivo: Este estudo teve como objetivo correlacionar aspectos clínicos e eletroencefalográficos associados a prognóstico em longo prazo de recém -nascidos (RN) com padrão de surto -supressão não reativo no EEG. Método: Foram selecionados para este estudo RN com EEG neonatal realizado no Laboratório de Neurofisiologia Clínica do Hospital São Lucas da PUCRS e acompanhados na mesma instituição, com idade concepcional superior a 37 semanas (na data do EEG), cujos registros estivessem disponíveis para revisão. Resultados: Foram incluídos 12 RN, 50% apresentaram crises convulsivas a partir do primeiro dia de vida. Em todos as convulsões eram refratárias ao tratamento medicamentoso. Em 50% a etiologia foi considerada criptogênica, 33% apresentavam erros inatos do metabolismo e 17% tinham história clíni-ca e achados de neuroimagem sugestivos de encefalopatia hipóxico -isquêmica. O seguimento clínico demonstrou que...