Neonatal encephalopathy (NE), previously known as neonatal hypoxic-ischemic encephalopathy (neonatal HIE or NHIE), is defined as a

encephalopathy Encephalopathy (; from grc, ἐνκέφαλος "brain" + πάθος "suffering") means any disorder or disease of the brain, especially chronic degenerative conditions. In modern usage, encephalopathy does not refer to a single disease, but r ...

syndrome with signs and symptoms of abnormal neurological function, in the first few days of life in an infant born after 35 weeks of gestation. In this condition there is difficulty initiating and maintaining respirations, a subnormal level of consciousness, and associated depression of tone, reflexes, and possibly seizures. Encephalopathy is a nonspecific response of the brain to injury which may occur via multiple methods, but is commonly caused by

birth asphyxia Perinatal asphyxia (also known as neonatal asphyxia or birth asphyxia) is the medical condition resulting from deprivation of oxygen to a newborn infant that lasts long enough during the birth process to cause physical harm, usually to the brain. ...

, leading to

cerebral hypoxia Cerebral hypoxia is a form of hypoxia (reduced supply of oxygen), specifically involving the brain; when the brain is completely deprived of oxygen, it is called ''cerebral anoxia''. There are four categories of cerebral hypoxia; they are, in o ...

Signs and symptoms

In neonates born at or beyond 35 weeks, neonatal encephalopathy may present itself as the following symptoms: * Reduced level of consciousness * Seizures (which peak at 48 hours) * Difficulty initiating and maintaining respiration * Depression of tone and reflexes

Diagnosis

Cord blood gas analysis can be used to determine if there is perinatal hypoxia/asphyxia, which are potential causes of hypoxic-ischemic encephalopathy or cerebral palsy, and give insight into causes of intrapartum fetal distress. Cord blood gas analysis is indicated for high-risk pregnancies, in cases where C-sections occurred due to fetal compromise, if there were abnormal fetal heart rate patterns, Apgar scores of 3 or lower, intrapartum fever, or multifetal gestation. Evidence of brain injury related to the hypoxic-ischemic events that cause neonatal encephalopathy can be seen with brain MRIs,

CTs Cts or CTS may refer to: Arts and entertainment Television * Chinese Television System, a Taiwanese broadcast television station, including: ** CTS Main Channel () ** CTS Education and Culture () ** CTS Recreation () ** CTS News and Info () ...

, magnetic resonance spectroscopy imaging or ultrasounds. Neonatal encephalopathy may be assessed using Sarnat staging. Brain MRI is usually performed within eight days of life. Features that can be seen on MRI brain are:

periventricular leukomalacia Periventricular leukomalacia (PVL) is a form of white-matter brain injury, characterized by the necrosis (more often coagulation) of white matter near the lateral ventricles. It can affect newborns and (less commonly) fetuses; premature infan ...

basal ganglia The basal ganglia (BG), or basal nuclei, are a group of subcortical nuclei, of varied origin, in the brains of vertebrates. In humans, and some primates, there are some differences, mainly in the division of the globus pallidus into an exter ...

and

thalamus The thalamus (from Greek θάλαμος, "chamber") is a large mass of gray matter located in the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, ...

lesions, and multicystic encephalopathy. Besides that,

diffusion MRI Diffusion-weighted magnetic resonance imaging (DWI or DW-MRI) is the use of specific MRI sequences as well as software that generates images from the resulting data that uses the diffusion of water molecules to generate contrast in MR images. It ...

would show low apparent diffusion coefficient (ADC) values in the first seven days of life. This is followed by pseudonormalisation of ADC values (normalisation of ADC values despite having persistent underlying brain injuries) which can persists up to two weeks.

Treatment

In the past, treatment options were limited to supportive medical therapy. Currently, neonatal encephalopathy is treated using hypothermia therapy. This has been shown to reduce brain damage, reduce future disability, and improve survival. Hypothermia therapy is also sometimes termed hypothermic neural rescue therapy. Clinical trials are taking place to investigate the effectiveness of stem cell-based interventions, which are thought to have the potential to reduce mortality and improve the long-term development of newborn infants with neonatal encephalopathy.

Prognosis

HIE is a major predictor of neurodevelopmental disability in term infants. 25 percent have permanent neurological deficits.

Epidemiology

Overall, the relative incidence of neonatal encephalopathy is estimated to be between 2 and 9 per 1000 term births. 40% to 60% of affected infants die by 2 years old or have severe disabilities. In 2013 it was estimated to have resulted in 644,000 deaths down from 874,000 deaths in 1990.

References

External links

{{Authority control Neonatology Neurological disorders in children