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Introduction: The occurrence of a burst-suppression EEG (BS-EEG) after cardiopulmonary resuscitation implies a poor prognosis, but little is known about the temporal dynamics of this EEG pattern. Methods: We studied 36 consecutive patients, who developed a burst-suppression EEG within 6 to 24 hours after cardiopulmonary resuscitation. Six patients died within 24 hours after the initial BS-EEG leaving 30 patients, who were followed with serial EEG recordings. Results: Except in one patient, BS-EEG was followed by another EEG pattern within one day: areactive α-coma-EEG (n = 9), generalised continuous epileptiform discharges (n = 6), isoelectric EEG (n = 5), θ EEG (n = 5), flat (i. e. less than 20 µV) recordings (n = 3), δ EEG (n = 1). Serial recordings disclosed a variety of EEG sequences composed of these EEG patterns including reappearance of a BS-EEG. 15 of the 36 patients also had coexistence of different EEG patterns in the same recording, mainly BS-EEG with episodes of continuous epileptiform discharges, which was seen in 10 patients. 31 patients died within 12 days, 5 remained in a persistent vegetative state. Conclusions: Postanoxic BS-EEG is a transient EEG-pattern implying a poor prognosis. It is followed by a variety of EEG sequences composed of different EEG patterns, each of which is recognised as an unfavourable sign by itself. Coexistence of different unfavourable EEG patterns in the same recording and transitions between these EEG patterns in subsequent recordings are common in patients with postanoxic BS-EEG. BS-EEG and subsequently evolving EEG patterns in anoxic encephalopathy reflect different forms of dysfunction of severely damaged neocortical neurons, which occur at different stages of a dynamic process finally leading to severe neuronal loss.