ReviewIctal–interictal continuum: A proposed treatment algorithm
Section snippets
Background
Continuous electroencephalographic (cEEG) monitoring in the intensive care arena has brought increasing recognition to complex periodic and rhythmic electrographic patterns that occur with relatively high frequency in critically ill patients. These patterns are typically recognized during coma and do not meet definitive criteria for either an ictal or interictal pattern but rather lie along a spectrum commonly referred to as the ictal–interictal continuum (IIC) (Brenner, 2009, Chong and Hirsch,
Proposed treatment algorithm
We propose a practical treatment algorithm that could help decision making when confronted with EEG patterns that fall along the ictal–interictal continuum in critically ill adult patients (Fig. 1). This algorithmic approach takes into account associated clinical events, clinical risk factors as well as what is currently known regarding the association of seizures and potential neuronal injury of various EEG patterns and characteristics. In addition, response to the administration of a
Case examples
Below we present case examples of patients with patterns that lie along the IIC. Management of these different clinical situations is presented for the purpose of illustrating use of the proposed treatment algorithm.
Conclusion
Continuous EEG monitoring in ICU is a field that has been rapidly expanding in the last 10 years. The technique provides physicians with a sensitive and quick way to identify malignant EEG patterns in critically ill patients that may impact their clinical course and prognosis. There are a number of lines of evidence supporting the idea that nonconvulsive seizures and possibly PDs may result in secondary neuronal injury and worse outcome, therefore warranting treatment (Drislane, 1999,
Conflict of interest
Valia Rodríguez and Megahn F. Rodden declare that they have no conflict of interest. Suzette M. LaRoche declares that she has received royalties from Demos Publishing.
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2020, Epilepsy and BehaviorCitation Excerpt :Based on EEG response, a second ASM can be added if clinical or electrographic improvement is not seen. The alternative method is to start more aggressively with intravenous anesthetics which will increase the risk of cardiorespiratory depression but provides greater chance of a rapid and effective treatment in order to prevent secondary neuronal injury [68]. Sometimes, these patterns can be refractory to initial therapies and could require continuous infusion of sedative-anesthetic drugs such as midazolam and propofol for adequate treatment [72].
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These authors contributed equally to this article.