Status epilepticus is a potentially life-threatening acute complication characterized by ongoing seizure activity of more than 5 minutes that requires immediate medical treatment.
Epilepsy is a chronic neurological disorder defined as the occurrence of 2 or more unprovoked or reflex seizures at least 24 hours apart, the occurrence of a single unprovoked or reflex seizure in an individual with an underlying condition that increases the risk of subsequent seizures (e.g., a brain tumor), or the presence of an epilepsy syndrome (see also “ Generalized epilepsy in childhood” for individual epilepsy syndromes).Īcute complications of seizures with potentially long-term consequences include physical trauma and CNS tissue damage due to hyperthermia, cardiorespiratory deficits, or excitatory toxicity. Seizures can also be classified by onset as focal (arising from discharges in one hemisphere), generalized (arising from discharges in both hemispheres), or of unknown onset. Reflex seizures are seizures that occur consistently in response to a particular trigger. Acute symptomatic seizures ( provoked seizures) have identifiable precipitating factors (e.g., stroke, traumatic brain injury, alcohol withdrawal), whereas unprovoked seizures occur in the absence of identifiable causes. Seizures can be triggered by a variety of circumstances depending on age, environmental factors, and underlying conditions. The underlying cause of seizures is a state of neuronal hyperexcitability that may be temporary (e.g, due to electrolyte imbalances) or more permanent in nature (e.g., due to inherited or acquired neural abnormalities). A seizure is the transient manifestation of abnormal excessive or synchronous electrical brain activity that causes convulsions, loss of consciousness, and or lapses of consciousness.