K Seizures
Incidence and prevalence
Seizures are one of the most common neurologic disorders and may occur at any age. Seizures affect approximately 0.5% to 1% of the population in the United States. Numerous types of seizures exist, but most are generalized tonic-clonic seizures. The likelihood of a recurrent seizure after a single seizure is approximately 50% in the following 3 years, with the greatest incidence during the first 6 months.
Pathophysiology
Seizures are caused by transient, paroxysmal, and synchronous discharge of groups of neurons in the brain. Most seizures are idiopathic. Idiopathic seizure disorders usually begin in childhood. Seizure onset in adults may indicate an expanding intracranial hematoma, tumor, intracranial hemorrhage, metabolic disturbance, infection, trauma, alcohol or addictive drug withdrawal, eclampsia (in pregnant women), previous trauma causing an irritative phenomenon in the brain, or local anesthesia toxicity.
Clinical manifestations
Clinical manifestations depend on location, number of neurons involved in the seizure, discharge, and duration of the seizure. Clinical manifestations include focal or generalized tonic-clonic seizures and an increase in the cerebral metabolic rate for oxygen. Cerebral metabolic decompensation occurs after 30 minutes of uncontrolled seizure activity. Therefore, the window for treatment is limited.