The EEG of status epilepticus

Gastaut noted that there are as many forms of status epilepticus (SE) as there are seizure types. The pleomorphic EEG patterns reflect this wide variety of clinical types. The different electroclinical types of status epilepticus share EEG characteristics including rhythmic activity, epileptiform discharges, and often a waxing and waning evolution. Gray zones of interpretation exist in the form of runs of epileptiform periodic discharges, typically of lower frequency, and lesser temporal variability. In diagnosing SE, clinical correlation and response to parenteral anti-epileptic drugs (AEDs) are of particular importance. Accurate diagnosis of electroclinical SE type is essential, because it determines prognosis and dictates the intensity of therapeutic management. Some patients with benign forms of SE may benefit from nonparenteral treatment, and be followed up clinically and by spot EEGs. Conversely, intensive care unit management with anesthesia and continuous monitoring, and parenteral AEDs may be required for refractory convulsive SE.