Neonatal encephalopathy following fetal distress. A clinical and electroencephalographic study.
Twenty-one neonates of over 36 weeks' gestation suffered perinatal asphyxia but not chronic hypoxia. Three clinical stages of postanoxic encephalopathy were distinguished. Stage 1 lasted less than 24 hours and was characterized by hyperalertness, uninhibited Moro and stretch reflexes, sympathetic effects, and a normal electroencephalogram. Stage 2 was marked by obtundation, hypotonia, strong distal flexion, and multifocal seizures. The EEG showed a periodic pattern sometimes preceded by continuous delta activity. Infants in stage 3 were stuporous, flaccid, and brain stem and autonomic functions were suppressed. The EEG was isopotential or had infrequent periodic discharges. Infants who did not enter stage 3 and who had signs of stage 2 for less than five days appeared normal in later infancy. Persistence of stage 2 for more than seven days or failure of the EEG to revert to normal was associated with later neurologic impairment or death.
D001927:Brain Diseases / Q000209:etiology* / Q000503:physiopathology; D003243:Consciousness; D005260:Female; D005316:Fetal Distress / Q000150:complications*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007232:Infant, Newborn, Diseases / Q000209:etiology* / Q000503:physiopathology; D009207:Myoclonus / Q000503:physiopathology; D010275:Parasympathetic Nervous System / Q000503:physiopathology; D011187:Posture; D011247:Pregnancy; D011379:Prognosis; D012640:Seizures / Q000503:physiopathology; D012890:Sleep; D013564:Sympathetic Nervous System / Q000503:physiopathology; D013997:Time Factors; D014851:Wakefulness