Most seizures end after a few moments or a few minutes. If seizures are prolonged, or occur in a series, there is an increased risk of status epilepticus. The term literally means a continuous state of seizure.
Status epilepticus is usually defined as 30 minutes of uninterrupted seizure activity. However, the Epilepsy Foundation advises parents and the public to call for emergency assistance when a convulsion continues for more than 5 minutes without signs of stopping.
Convulsive status epilepticus is a medical emergency. An estimated 42,000 deaths and thousands more instances of brain damage per year follow episodes of status.
Death or brain damage from status seizures (as opposed to death from the underlying cause) is most likely to result from:
- Direct damage to the brain caused by the injury that causes the seizures
- Stress on the system from repeated generalized tonic clonic seizures
- Injury from repeated electrical discharge in the brain.
The goal of treatment is to stop the seizure activity as quickly as possible and treat any underlying precipitant. Mortality in children and adults is minimized when status lasts less than one hour. After an hour it increases slightly in children but jumps dramatically to close to 38% in adults.
Any type of epileptic seizure can progress to status epilepticus, but convulsive status has the greatest potential for long-term damage. Mice lacking a sodium channel in neurons display the severe epileptic seizures typical of Dravet syndrome. learn more