[Neonatal hypoxic-ischemic encephalopathy]

Abstract

Hypoxic-ischemic encephalopathy is a clearly recognizable clinical syndrome of in term newborns due to fetal asphyxia at birth. The incidence is 1.5 (95% CI 1.3 to 1.7) but it ranges from 1-8 and 25 out of every 1000 born in developed and developing countries, respectively. The most frequent causes are detachment of the placenta, prolapse of the umbilical cord and uterine rupture. The diagnostic criteria include partial or total incapacity for the newborn to cry and breath at birth even when stimulated, requiring assisted ventilation in the delivery room, Apgar < 5 in 5 and 10 minutes, acidemia (pH ≤ 7 and / or bases deficit ≥ 12 mmol/l), alterations of the conscience and the reflexes of Moro, grasping and suction, muscular stretching and muscle tone. The clinical forms are mild, moderate and severe. In the mild forms, the recovery is total in three days without, or with minimal, neurodevelopmental alterations. The moderate and severe forms cause permanent neurological deficits and neurodevelopmental alterations (48%) or death (27%). The regular or amplitude integrated EEG and the magnetic and spectroscopic magnetic resonance imaging performed between 24 and 96 hours and 7 and 21 days after birth, respectively, have a high diagnostic and prognostic value. Induced hypothermia (33.5° C for 72 hours) is recommended before 6 hours old. The result is a decrease in mortality (from 35% to 27%) and morbidity (from 48% to 27%).

Keywords: asphyxia neonatorum; induced hypothermia; neonatal encephalopathy.