Neonatal seizure

rdf:langString Neonatal seizure

rdf:langString Neonatal seizure

rdf:langString Neonatal seizure

rdf:langString Seizures in neonates

rdf:langString A neonatal seizure is a seizure in a baby younger than age 4-weeks that is identifiable by an electrical recording of the brain. It is an occurrence of abnormal, paroxysmal, and persistent ictal rhythm with an amplitude of 2 microvolts in the electroencephalogram, detected in infants younger than 4 weeks. These may be manifested in form of stiffening or jerking of limbs or trunk. Sometimes random eye movements, cycling movements of legs, tonic eyeball movements, and lip-smacking movements may be observed. Alteration in heart rate, blood pressure, respiration, salivation, pupillary dilation, and other associated paroxysmal changes in the autonomic nervous system of infants may be caused due to these seizures. Often these changes are observed along with the observance of other clinical symptoms. A neonatal seizure may or may not be epileptic. Some of them may be provoked by stimulation or suppressed by restraining them. According to the International League against Epilepsy (ILAE), seizures are basically abnormally excessive or synchronous neuronal activity in the brain that is manifested as signs or symptoms. This definition, however, excludes the electrographic-only seizures that comprise 40-60% of that found in critically ill neonates. As per the classification system by the American Clinical Neurophysiology Society, seizures can be classified into electroclinical, clinical only, and electrographic-only seizures. Neonatal seizures have been classified into various types depending on various parameters. The earlier classification system, focused more on differentiating these neonatal seizures from those experienced in adult children. Neonates were found to experience either tonic or clonic seizures. They did not experience tonic-clonic seizures. If seizures were found to be focal, they were further classified into unifocal or multifocal. Seizures in the neonatal population can be mainly categorized into acute symptomatic seizures and neonatal epilepsy that is related to genetic or structural factors. Brain injury due to hypo-ischemic encephalopathy, ischemic stroke, intracranial hemorrhage or infection, inborn errors of metabolism, transient metabolic and brain malformations, lead to acute symptomatic seizures. Neonatal epilepsy may be credited to genetic syndromes, developmental structural brain abnormalities, or metabolic diseases. All the classification systems are found to be highly useful clinically. The incidence of seizures is more common in the neonatal stage than in other stages of life. Neonatal seizures are comparatively rare and affect 1 or 3.5 in 1000 infants born. They are the most frequent neurological problem in the nursery that is associated with greater risks of morbidity and mortality, often requiring evaluation and treatment in a neonatal intensive care unit. Better care delivered in neonatal care units, with improved healthcare facilities, has decreased the mortality rate associated with these seizures. However, the long-term morbidity rate remains approximately the same. The increased risk of neonatal seizures may be attributed to risks related to delivery, gestation, post-natal period, and physiological factors. Neonatal seizures are generally subclinical and their diagnosis based on the clinical observations is generally difficult. Especially the seizures that involve senses are hard to detect in neonates. Diagnosis relies on identification of the cause of the seizure, and verification of actual seizure activity by measuring electrical activity with electroencephalography (EEG). The set of guidelines developed by the American Clinical Neurophysiology Society helps the healthcare providers know when the EEG is appropriate and corresponds to the seizures. Treatment depends generally on the underlying cause of the seizure. Administration of deficient chemicals that lead to seizures treats it but if it still persists and is confirmed by EEG, pharmacologic treatment with anti-epileptic drugs is administered. The considerable debate about the long-term consequence of a neonatal seizure exists between data and deductions reached through animal experimentations and those obtained through clinical investigations. The main conflicting issues are whether seizures in newborns can plant the roots for epileptogenesis and cause long-term deficits. Fewer than half of the affected infants develop seizures in later life. Such neonatal seizures are considered self-limited, and thus the term neonatal epilepsy is not used to describe these seizures. It has been estimated that approximately 15% of neonatal seizures represent epilepsy syndrome. The incidence of neonatal seizures has not been clearly established, although an estimated frequency of 80-120 cases per 100,000 neonates per year has been suggested. The incidence of seizures is higher in the neonatal period than at any other time of life, and most often occurs in the first week of life.