Neonatal Seizures Syndrome

Neonatal seizure syndromes are pathological discharges in the brain of newborns, manifesting as stereotyped muscular activity or autonomic changes. The diagnosis is made by EEG. To clarify the causes appropriate investigations should be initiated. Treatment depends on the cause.

Seizure disorders.

Neonatal seizure syndromes are pathological discharges in the brain of newborns, manifesting as stereotyped muscular activity or autonomic changes. The diagnosis is made by EEG. To clarify the causes appropriate investigations should be initiated. Treatment depends on the cause. Seizure disorders. Seizures occur in 1.4% of newborns and 20% of preterm infants. Seizures can be a serious neonatal problem and should be investigated immediately. Most newborn seizures are focal, as in newborns a generalization of an electric discharge by the lack of myelination and incomplete formation of dendrites and synapses in the brain prevents the newborn. Some newborns who receive an EEG study due to seizures or other symptoms of encephalopathy (z. B. hypoactivity, decreased reactions) show clinically silent attacks (? 20 seconds rhythmic epileptiform electrical activity in the EEG without clinically visible seizure activity). Sometimes these clinically silent seizures last for> 20 min on; At this time, these discharges are then called electrical status epilepticus. Etiology The abnormal electrical discharge in the central nervous system can be caused by a primary intracranial process (eg. As meningitis, ischemic stroke, encephalitis, intracranial hemorrhage, tumor, malformation) a systemic problem (z. B. hypoxia-ischemia, hypoglycemia, hypocalcemia, hyponatremia and other metabolic disorders) seizures by intracranial processes can typically based on clinical symptoms are indistinguishable from the symptoms that are due to systemic diseases (eg. as focal versus generalized). Hypoxic ischemia, the leading cause of neonatal seizures may, before, during or after childbirth occur (overview of perinatal respiratory distress syndrome). These attacks can be severe and difficult to treat, but they tend to subside after 3-4 days. When a neonatal hypoxia is treated with therapeutic hypothermia (usually whole-body cooling), attacks may be less severe, but even during the reheating recur. An ischemic stroke is more common in infants with polycythemia or thrombophilia due to a genetic disorder or severe hypotension, sometimes without any risk factor. The strokes typically occur in the distribution area of ??the middle cerebral artery or its peripheral areas. Seizures that are caused stroke, are more focal nature and cause apnea. Infections such as meningitis or sepsis can cause seizures. In such cases, the attacks are often accompanied by other symptoms and signs. Group B Streptococcus and Gram-negative bacteria are common causes of these infections in newborns. Also encephalitis due to cytomegalovirus, herpes simplex virus, rubella virus, Treponema pallidum or Toxoplasma gondii can cause seizures. Hypoglycemia is common in newborns whose mothers have diabetes, who are small for gestational age or who had a stroke or hypoxic exposed other stresses. The attacks by hypoglycaemia are focal and variable. Prolonged or repeated episodes of hypoglycaemia can permanently damage the brain. Intracranial bleeding, including subarachnoid, intracerebral and intraventricular hemorrhage, the cause of seizures can be. Intraventricular bleeding, which occur more frequently in premature infants, are the result of hemorrhage in the germinal matrix (a region which adjoins the ventricle and in the produced during development neurons and glial cells). A hypernatremia or hyponatremia can cause seizures. Hypernatremia may be the result of accidental oral or intravenous sodium chloride overload. Hyponatremia can be achieved by dilution (p.o. when administering too much water or iv) be caused by sodium or losses in stool or urine. Hypocalcaemia (calcium serum levels <[<1.87 mmol / l] 7.5 mg / dL typically occurs together with a phosphate serum levels of> 3 mg / dl) be asymptomatic (> 0.95 mmol / l) and can , Premature birth or difficult birth are risk factors for hypocalcemia. Hypomagnesämieist a rare cause of seizures. The serum magnesium levels are (<0.7 mmol / l) at <1.4 mEq / l. Hypomagnesemia often occurs along with hypocalcemia and should be considered in neonates with hypocalcemia considered if the attacks continue persist despite adequate calcium therapy. Inborn errors of metabolism (eg., Amino, or organic aciduria) can cause neonatal seizures. A rare cause of seizures is a pyridoxine, which is easy to treat. CNS malformations can also cause seizures. Maternal drug use (eg. As of cocaine, heroin, diazepam) is a growing problem, seizures can occur after birth by an acute withdrawal. Neonatal seizures may have a familial or genetic causes. Benign familial neonatal convulsions are a pathology of Kaliumionenkänale that are inherited in an autosomal dominant manner. Early infantile epileptic encephalopathy (Ohtahara syndrome) is a rare disorder that is associated with a variety of mutations. Symptoms and complaints Neonatal seizures are usually focal and difficult to detect. Häufge manifestations include. a. clonic small, jerky movements of the limbs, or alternating Hemianfälle primitive subcortical seizures (including a apnea, lip-smacking, lasting Blickdeviationen or nystagmus similar movements and episodic changes in muscle tone cause). Generalized tonic-clonic seizures are rare. Clinically silent electrical seizure activity often comes after a hypoxic-ischemic injury (including perinatal asphyxia or stroke) before and in neonates with CNS infections, especially after an initial treatment with anticonvulsants, including a befitting a stop of clinical signs than stop the electrical seizure activity leads. Diagnostic EEG laboratory tests (eg., Glucose in serum electrolytes, cerebrospinal fluid, urine and blood cultures) Usually cranial imaging The investigation begins with a detailed family history and clinical examination. Tremor (alternating contraction and relaxation of muscles in the opposite extremities) must be distinguished from real attacks. Tremor is usually induced stimulus and can be terminated by the limb is kept quiet. In contrast, seizures begin spontaneously, and motor activity is also noticeable when you shut holds the limb. A EEG (waking and sleeping) EEG is especially important when it is difficult to determine whether the newborn has seizures. The EEG is also useful for monitoring therapeutic success, the EEG should cover active and quiet sleep periods and sometimes requires a duration ? 2 hours. A normal EEG with the expected differences during sleep is a good prognostic sign, as opposed to an EEG with diffuse severe pathologies (eg. As low voltage or suppressed discharge patterns). EEG at the bedside with video surveillance for h ? 24 can detect clinically silent electric current seizures, especially in the first few days after a CNS Schädigung.Labortests laboratory tests that are looking for underlying treatable diseases should be immediately performed; the tests include a pulse oximetry, the determination of serum glucose, -sodium, -potassium, chloride, bicarbonate, and -Kalzium-magnesium, a lumbar puncture for CSF analysis (cell number and differentiation, glucose, protein), and a culture include. Furthermore, urine and blood cultures should be. Depending on the clinical situation also other metabolic studies (z. B. blood gases, arterial pH, bilirubin, urea and organic acids) or a drug screening should be based on the commonly used drugs (which are transplacentally, or through the mother's milk enters the newborn) are performed. Imaging tests Imaging tests are usually done if the cause is not immediately apparent (eg. as glucose or electrolyte abnormality). MRI is preferred, but is may not be immediately available; in such cases, a cranial CT is performed. For very sick babies that can not be brought into the radiology, a cranial ultrasound is performed at the bedside; he can intraventricular, but do not recognize subarachnoid hemorrhage. MRI or CT is performed when the infants are stable. Cranial CT can detect intracranial bleeding and some malformations. The MRI shows abnormalities more clearly and can recognize after its occurrence ischemic tissue within a few hours. The magnetic resonance spectroscopy can help to determine the extent of ischemic injury or identify the accumulation of certain neurotransmitters that are associated with an underlying metabolic disorder. Prognosis The prognosis depends on the histology: Approximately 50% of newborns with seizures due to hypoxic ischemia develop normally. Most neonates with seizures due to a subarachnoid hemorrhage, hypocalcemia, or hyponatremia is doing well. Infants with severe intraventricular hemorrhage have a high morbidity rate. In idiopathic or malformation induced seizures prognosis of neurodevelopment is worse, the earlier use the seizures. Whether neonatal seizures cause damage that is in excess of the underlying disorder is unknown. However, there is concern that the prolonged firing of nerve cells during prolonged bouts metabolic stress and thus cause additional brain damage could. The newborns have in acute brain injuries, such as hypoxic ischemia, stroke or infection, a whole series of seizures. However, typically these attacks stop after 3-4 days. but they can occur after months or years back when brain damage has occurred. Seizures resulting from other causes may persist more in the neonatal period. Treatment Treating the cause anticonvulsants Treatment focuses primarily on the underlying cause and secondary to the seizures. Treatment of the cause, at low serum glucose is 10% dextrose 2 ml / kg i.v. and added continuously monitored serum glucose. Optionally, additional infusions are administered, but carefully to avoid hyperglycemia. In a hypocalcemia 10% calcium gluconate 1 ml / kg i.v. given (9 mg / kg of elemental calcium); the dose may be repeated in recurrent hypocalcemic seizures. The infusion rate of the Kalziumglukonatinfusion should not exceed 0.5 ml / min (50 mg / min). A continuous cardiac monitoring is necessary during the infusion. Extravascular infusion should be avoided due to skin necrosis. In a hypomagnesemia 0.2 ml / kg (100mg / kg) of a 50% magnesium sulfate solution should i.m. are administered. Bacterial infections should be treated with antibiotics. Herpes encephalitis is with acyclovir behandelt.Antikonvulsiva anticonvulsants are used only when the seizures after correction of hypoglycemia, hypocalcemia, hypomagnesemia, hyponatremia, hypernatremia not suspend. Phenobarbital is still the drug that is most commonly used; the first dose is 15-20 mg / kg i.v. In case of persistent seizures can every 15-30 min 5 to 10 mg / kg i.v. be given until the seizures stop or until the maximum dose of 40 mg / kg was reached. If seizures stop, the maintenance therapy is begun approximately 24 hours later with 1.5 to 2 mg / kg every 12 hours and every 12 hours increased to 2.5 mg / kg, based on the clinical or EEG response, or the drug levels in the serum , In case of persistent or recurrent seizures phenobarbital is injected i.v. continued. When the Säuglin is stable, phenobarbital can be given daily orally 3 to 4 mg / kg once. The therapeutic serum levels are at 20-40 ug / ml (85-170 micromol / L). Levetiracetam is increasingly used to treat neonatal seizures, because it is less sedating than phenobarbital. It is i.v. administered intravenously as a 20 to 50 mg / kg given base dose and the therapy can be used as 10 to 30 mg / kg i.v. every 12 hours will be continued. The therapeutic levels are not well established in newborns. Fosphenytoin can be used if the attacks continue despite phenobarbital and levetiracetam. The initial dose is 20 mg PE (phenytoin equivalent) / kg i.v. You will be given 30 minutes to avoid hypotension and arrhythmias. A maintenance dose can then with 2-3 mg PE / kg take place every 12 hours, and then the clinical response or the serum level is adjusted. The therapeutic serum levels of phenytoin in neonates are at 8-15 ug / ml (32-60 .mu.mol / l). Lorazepam 0.1 mg / kg i.v. can be applied initially in an extended attack or in treatment-resistant seizures and 3 times are repeated every 5-10 min to within 8 h. Newborns who receive intravenous anticonvulsant drugs should be closely observed. High doses and combinations of drugs, especially lorazepam plus phenobarbital may lead to respiratory depression. The appropriate duration of therapy is known for any of the anticonvulsants, but if the seizures are under control, anticonvulsants can be stopped before release from the infant home. Important points Neonatal seizures usually occur in response to a systemic or CNS event on (z. B. hypoxia / ischemia, stroke, bleeding, infection, metabolic disorders, structural brain abnormality). Neonatal seizures are usually focal and difficult to detect. Häufge manifestations include. a. clonic cause small, jerky movements of the limbs, lip smacking, lasting Blickdeviationen or nystagmus similar movements and episodic changes in muscle tone. An EEG is essential for diagnosis. Laboratory tests and usually imaging procedures are performed to determine the cause. The treatment depends on the particular cause. Phenobarbital, levetiracetam are administered when the seizures not stop as soon as the cause has been eliminated; Fosphenytoin and lorazepam can be added for persistent seizures.

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