Fisiopatologia de las convulsiones

A review of the scientific foundations of current clinical practice

The Pathophysiology of Epileptic Seizures: A Primer For Pediatricians
Carl E. Stafstrom, MD, PhD* IntroductionSeizures are one of the most common neurologic disorders affecting children. As many as 5% of children experience a seizure during childhood. Although many epilepsies, especially refractory ones, aremanaged by specialists in pediatric neurology or epilepsy, general pediatricians often are called upon to manage children who have both acute and chronic seizures. Therefore, it is important tounderstand some of the basic pathophysiologic mechanisms underlying epileptic seizures. This understanding will allow the physician to choose the most appropriate medication for the given seizure type andclinical setting. Seizures can be a particular challenge to treat. Fortunately, in addition to the armamentarium of anticonvulsant agents previously available, a profusion of new antiepileptic drugs(AEDs) has appeared in the past 5 years. Some of these drugs are designed to address specific pathophysiologic defects in the sequence of events leading to the generation or spread of seizures. Thepurpose of this article is to review the principles of cellular neurophysiology as a
*Associate Professor of Pediatrics and Neurology, Tufts University School of Medicine; Director, Epilepsy Center forChildren, The Floating Hospital for Children at New England Medical Center, Boston, MA. 342

foundation for understanding how normal neuronal function goes awry in epilepsy. First, normal synaptictransmission and neuronal firing are summarized. Next, the pathophysiology of acute and chronic seizures is discussed. Finally, the mechanisms by which AEDs control the hyperexcitability that underliesepilepsy are considered.

Seizures and Epilepsy

A seizure is a temporary disruption of brain function due to the hypersynchronous, excessive discharge of cortical neurons....