Curative effect analysis of mild hypothermia in treatment of neonatal hypoxic-ischemic encephalopathy and follow-up study of 36 children aged 18 months

Abstract

Objective To explore the efficacy and safety of mild hypothermia(MH) in treating the infants with moderate-to-severe neonatal hypoxic-ischemic encephalopathy(HIE), and to make a follow-up of the nerve motor development of the infants at 18 months old after discharge. Methods Totally 61 neonates with moderate-to-severe HIE in Neonatal Intensive Care Unit (NICU) from Jan.2007 to Dec.2013 were retrospectively analyzed.According to before and after MH therapeutic apparatus was used by NICU of Shanghai Children's Hospital, 61 neonates of HIE were divided into 2 groups, the conventional treatment group(25 cases) and MH treatment group(36 cases). The patients in both groups were measured respectively by using the amplitude integrated electroencephalography(aEEG) before MH treatment and at 72 hours after MH treatment, by neonatal behavioral neurological assessment(NBNA) on the 28th day after birth, and by adopting Bayley Scales of Infant Development at 18 months old.The adverse reactions, serious disability cases and deaths of MH treatment were recorded. Results Compared with the conventional treatment group, aEEG recording before treatment showed no statistically significant differences in MH treatment group[maximum voltage: (22.4±3.1) μV vs(18.6±2.5) μV, maximum voltage: (8.2±2.6)μV vs(6.5±1.9) μV, t=1.264, 0.852, all P>0.05]. However, aEEG recording at 72 h after treatment showed statistically significant differences in MH treatment group[maximum voltage: (24.1±3.2) μV vs(30.6±2.8) μV, maximum voltage: (9.7±3.4)μV vs(13.3±2.2) μV, t=6.376, 4.257, all P<0.05]. Severe disability cases[24.0%(6/25 cases)vs 5.6%(2/36 cases), χ2=4.405, P<0.05] and deaths [16.0%(4/25 cases)vs 0(0/36 case), χ2=6.164, P<0.05] in MH treatment group were significantly decreased, and there was significantly difference in NBNA on the 28th day after birth[(35.9±2.1) vs(39.1±1.6), t=3.361, P<0.05], and scales of neurobehavioral evaluation through follow-up of 18 months old [mental development index(MDI): (85.2±10.7) vs(96.5±13.1), t=7.839, P<0.05]. Very few neonates had apnea, coagulation dysfunction, arrhythmia and other adverse reactions in MH treatment course. Conclusions MH treating moderate-to-severe HIE is safe and effective.MH is effective in reducing death and major disabilities in neonates with moderate-to-severe HIE and without significant side effects.MH can obviously improve the development of nervous system disorders in 0-18 months infants, and can significantly improve these infants' Bayley developmental scale neurobehavioral scores. Key words: Mild hypothermia; Infant, newborn; Hypoxic-ischemic encephalopathy; Prognosis; Follow-up