Seizures and Status Epilepticus
A seizure is a paroxysmal episode of abnormal electrical activity in the brain, resulting in involuntary transient neurologic, motor activity, behavioral, or autonomic dysfunction. Typically, seizures are divided into 2 major categories, partial and generalized. Although seizures can present with many different clinical manifestations, most fit into the subcategories of simple partial, complex partial, or generalized tonic–clonic. See Chapter 11 for detailed discussion of these categories.
Status epilepticus is defined as a prolonged seizure (30 minutes or longer) or as multiple seizures without intervening periods of normal consciousness. Like seizures, status epilepticus may have a local onset with secondary generalization or may be generalized from onset. This condition often occurs concomitantly with hyperthermia, acidosis, hypoxia, tachycardia, hypercapnia, and mydriasis and, if persistent, may be associated with irreversible brain injury. Status epilepticus that is completely stopped within 2 hours usually has relatively minor morbidity compared with episodes lasting longer than 2 hours.
Major causes of seizures and status epilepticus include
drug withdrawal, such as from anticonvulsants, benzodiazepines, barbiturates, or alcohol
metabolic abnormalities, such as hypoglycemia, hyponatremia, hypocalcemia, or hypomagnesemia
conditions that affect the CNS, such as infection, trauma, stroke, hypoxia, ischemia, or sleep deprivation
toxic levels of various drugs
Emergency medical management of seizures is best left to physicians who perform this routinely. However, the clinician should be aware of some general considerations in the treatment of seizures. The first priority is now the maintenance of circulation as opposed to airway maintenance. Maintenance of circulation becomes particularly important if the seizure progresses to status epilepticus.
During seizure management, it is important not only to stop the seizure activity but also to identify and treat the underlying cause when possible. Additional steps include noting the time of seizure onset, monitoring and maintaining an airway, and monitoring vital signs. Activation of the emergency response (911) team is indicated in all cases of acute seizure onset. In the setting of an ophthalmology office, it may be appropriate to check blood glucose levels, because many seizure patients have diabetes mellitus.
Refractory cases of status epilepticus have responded successfully to repeated electroconvulsive therapy sessions, IV sedatives such as ketamine or propofol, surgical ablation and stimulation procedures, and topiramate and levetiracetam.
Riviello JJ Jr, Claassen J, LaRoche SM, et al; Neurocritical Care Society Status Epilepticus Guideline Writing Committee. Treatment of status epilepticus: an international survey of experts. Neurocrit Care. 2013;18(2):193–200.
Excerpted from BCSC 2020-2021 series: Section 1 - Update on General Medicine. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.