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Non-convulsive Status Epilepticus and Non-convulsive Seizures in Neurological ICU Patients

Neurocritical Care volume 22, pages 202–211 (2015)Cite this article

Abstract

Background

Non-convulsive seizures (NCS) or non-convulsive status epilepticus (NCSE) has been reported in 8–20 % of critically ill patient populations, and delayed diagnosis and treatment of NCSE may lead to increased mortality. This study seeks to better understand the risk factors, characteristics, and outcome of NCS/NCSE in the neurological ICU.

Methods

This is a prospective observational study, recruiting consecutive patients admitted to the adult neurological ICU with altered mental status. Patients with anoxic brain injury were excluded from the study. Data were collected and analyzed for prevalence of NCSE/NCS, EEG patterns, associated risk factors, treatment response, and final outcome.

Results

NCSE/NCS was detected in 21 % of 170 subjects. Clinical seizures preceded EEG diagnosis of NCSE/NCS in 25 % of cases. Significant risk factors for NCSE/NCS were a past medical history of intracranial tumor, epilepsy, or meningitis/encephalitis, or MRI evidence of encephalomalacia. Subtle clinical findings such as twitching of oral or ocular muscles and eye deviations were found on exam in 50 % of the NCSE/NCS group. Mortality was increased in NCSE cases as 31 % of NCSE/NCS patients died compared to 14 % in non-NCSE/NCS group.

Conclusions

Specific clinical features along with history and imaging findings may be used to identify patients at high risk of NCSE/NCS in the neurological ICU.

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Conflict of interest

Ikuko Laccheo, Hasan Sonmezturk, Amar Bhatt, Luke Tomycz, Yaping Shi, Marianna Ringel, Gina DiCarlo, DeAngelo Harris, John Barwise, and Bassel Abou-Khalil declare that they have no conflicts of interest.

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Authors and Affiliations

  1. Epilepsy Center of Excellence, Veterans Affairs Medical Center, Richmond, VA, USA

    Ikuko Laccheo

  2. Virginia Commonwealth University, Richmond, VA, USA

    Ikuko Laccheo

  3. Vanderbilt University Medical Center, Nashville, TN, USA

    Hasan Sonmezturk, Amar B. Bhatt, Yaping Shi, Marianna Ringel, Gina DiCarlo, DeAngelo Harris, John Barwise, Bassel Abou-Khalil & Kevin F. Haas

  4. Seattle Children’s Hospital, Seattle, WA, USA

    Luke Tomycz

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  1. Ikuko Laccheo
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Correspondence to Ikuko Laccheo.

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Laccheo, I., Sonmezturk, H., Bhatt, A.B. et al. Non-convulsive Status Epilepticus and Non-convulsive Seizures in Neurological ICU Patients. Neurocrit Care 22, 202–211 (2015). https://doi.org/10.1007/s12028-014-0070-0

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Keywords

  • Neurological ICU
  • Critical care
  • Altered mental status
  • Non-convulsive seizures
  • Non-convulsive status epilepticus
  • EEG