How I Treat Patients with EEG Patterns on the Ictal–Interictal Continuum in the Neuro ICU

Refractory status epilepticus (RSE) is associated with a high risk of poor outcome and treated by most neurointensivists with continuous intravenous antiepileptic medications (cIV-AEDs). Continuous EEG monitoring has allowed us to unveil a number of epileptiform patterns of less certain significance. These have been labeled ictal to interictal continuum (IIC), many of which are associated with poor outcome. It is unclear to which extent individual patterns are epiphenomena or lead to additional brain injury. The treatment of these patterns is highly controversial and guidelines how to manage them are non existent. In this review of a challenging case, I will discuss a number of approaches to determine the ictal nature of the IIC in an effort to minimize neuronal injury from epileptiform brain activity on the one hand and from the treatment on the other hand. Ultimately it will be most important to replace the dichotomy of ictal versus non-ictal patterns by differentiating between harmful and non-harmful patterns.

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