Status epilepticus

A life-threatening neurologic condition defined as 5 or more minutes of either continuous seizure activity or repetitive seizures without regaining consciousness.

Generalized convulsive status epilepticus (SE) in both its subtle and overt subtypes constitutes the most frequent variant.

Diagnosis of nonconvulsive SE can be difficult, but recognition is crucial because rapid termination helps prevent serious brain injury, especially in patients with impaired consciousness.

In most cases, treatment must precede any thorough investigation and must be initiated as soon as SE is suspected.

Treatment involves a stepwise medication approach aimed at aborting the clinical and electrographic seizures.

Carries a high mortality rate and may cause serious complications if not promptly treated.

Generalized convulsive and nonconvulsive status epilepticus (SE) are neurologic and medical emergencies defined as 5 or more minutes of either continuous seizure activity or repetitive seizures with no intervening recovery of consciousness.[1]Lowenstein DH, Bleck T, Macdonald RL. It's time to revise the definition of status epilepticus. Epilepsia. 1999 Jan;40(1):120-2. http://www.ncbi.nlm.nih.gov/pubmed/9924914?tool=bestpractice.com [2]Brophy GM, Bell R, Claassen J, et al; Neurocritical Care Society Status Epilepticus Guideline Writing Committee. Guidelines for the evaluation and management of status epilepticus. Neurocrit Care. 2012 Aug;17(1):3-23. http://www.ncbi.nlm.nih.gov/pubmed/22528274?tool=bestpractice.com Traditionally SE was defined as 30 or more minutes; however, this time frame has been reduced to 5 minutes to emphasize the seriousness of the condition and the need to treat it urgently.[2]Brophy GM, Bell R, Claassen J, et al; Neurocritical Care Society Status Epilepticus Guideline Writing Committee. Guidelines for the evaluation and management of status epilepticus. Neurocrit Care. 2012 Aug;17(1):3-23. http://www.ncbi.nlm.nih.gov/pubmed/22528274?tool=bestpractice.com [3]Lowenstein DH, Alldredge BK. Status epilepticus. N Engl J Med. 1998 Apr 2;338(14):970-6. http://www.ncbi.nlm.nih.gov/pubmed/9521986?tool=bestpractice.com

In the 2017 International League Against Epilepsy (ILAE) classification of seizures paper, convulsive seizures are termed "focal to bilateral tonic-clonic" seizures if they are focal in onset, and "generalized tonic-clonic" if they are generalized in onset.[4]Fisher RS, Cross JH, French JA, et al. Operational classification of seizure types by the International League Against Epilepsy: position paper of the ILAE Commission for Classification and Terminology. Epilepsia. 2017 Apr;58(4):522-30. https://onlinelibrary.wiley.com/doi/full/10.1111/epi.13670 http://www.ncbi.nlm.nih.gov/pubmed/28276060?tool=bestpractice.com As the time of onset of a seizure may be unknown when a patient presents to medical attention in SE and as both types of convulsive SE are treated identically, for the purposes of this topic, the categories "generalized convulsive SE" and "nonconvulsive SE" will be used.