UMEM Educational Pearls

Category: Critical Care

Title: Beware of Non-Convulsive Status Epilepticus

Keywords: Status epilepticus, non-convulsive, altered mental status, seizure, critical care, ICU, neurology (PubMed Search)

Posted: 11/23/2010 by Haney Mallemat, MD
Click here to contact Haney Mallemat, MD

Non-Convulsive Status Epilepticus (NCSE) is generally under reported. An ICU study found 10% admissions for altered mental status (AMS) were eventually diagnosed as NCSE.


- Include NCSE in the AMS differential

- NCSE may occur with or without convulsive seizures

- Difficult to distinguish from a post-ictal state (14% of convulsive seizures convert to  


- Reported mortality is up to 44%


Consider NCSE when:

- Seizure history / recent seizures

- Post-ictal period >1 hour

- Odd behaviors (e.g., chewing, blinking, personality change) and abnormal eye 

  movements (86% specific)

- AMS without structural, metabolic or traumatic etiology

- Patient intubated for status epilepticus 


If you are unsure but suspicious of NCSE order a STAT EEG.  Treat NCSE like a convulsive status.


Slattery, D. Seizures as a cause of altered mental status. Emerg Med Clin North Am. 2010 Aug;28(3):517-34.