Neonatal EEG trace of burst-suppression etiological and evolutionary factors

Introduction. The electroencephalographic (EEG) trace seen during the neonatal period which shows so-called discharges of burst-suppression, is caused by a severe disorder of cerebral electrogenesis occurring at this time. Objective. To determine the aetiology, clinical significance and evolution of a group of newborn babies with this type of EEG trace. Patients and methods. We made a retrospective study of fullterm babies in whom burst-suppression EEG recordings had been obtained during the neonatal period. Results. We studied 34 patients. In 14 cases the trace was associated with hypoxic-ischemic encephalopathy; 4 with meningitis; another 4 with early infantile epileptic encephalopathy (Ohtahara syndrome); 4 cases were attributed to drugs (4 with fentanyl associated in one case with phenobarbitone and in another with midazolam): 2 cases were due to early myoclonic epilepsy; 3 to multiple organ failure; one to non-ketotic hyperglycinemia and another to leucinosis. In one patient the aetiology could not be determined. Seven patients died before the age of 6 months. Severe neurological seguelae were seen in all the others except for four cases (3 treated with fentanyl and one case with hypoxic-ischemic encephalopathy). Conclusions. The presence of a burst-suppression EEG trace in a neonate makes extensive study to determine the aetiology necessary. Although associated with a worse prognosis, those not treated with piperidine derivatives should be classified separately. Those treated with piperidine derivatives have a good prognosis.