Effects Of Mild Hypothermia On Cerebral Oxygen Saturation In Neonates With Hypoxic Ischemic Encephalopathy

Objective:We monitor the newborns owed thirty-sixs’ s pregnance’s relative cerebral hemoglobin oxygen saturation(rSO2),who have hypoxic ischemic encephalopathy(HIE),in,before and after the mild hypothermia therapy,as well as the conventional therapy in the same time.To konw the comparisons of rSO2 between mild hypothermia therapy and conventional therapy.Looking for the evidence of mild hypothermia therapy for HIE.Methods:From March 2015 to November 2016,95 newborns were diagnosised with HIE,who were hospitalized in the Affiliated Hospital of Southwest Medical University and met the test requirments as the research objects.They are divided into four groups,according to their admission time in the hospital is within 6hours or not and their familiers’ wishes about mild hypothermia therapy.Group A in mild hypothermia therapy within 6 hours has 37cases;Group B in conventional symptomatic treament within 6 hours has21 cases;Group C in mild hypothermia therapy within 12 hours has 18cases;Group D in conventional symptomatic treament within 12 hours has 19 cases.Their rSO2 were monitored in,before and after the treatment.The amplitude-integrated electroencephalogram(aEEG)statusof the four groups were measured in their fourth day.The neuron-specific enolase(NSE)test were performed within 2 hours after their admissions in the hospital and 6-7 days after their admissions in the hospital.Results:1.There was no significant difference in gestational age,birth weight and sex among the 4 groups(P > 0.05).2.There was no significant difference in rSO2(P > 0.05)between the two groups of newborns with HIE admitted to hospital within 6 hours;The mild hypothermia group’s rSO2 was lower in the mild hypothermia treatment(72 hours),the difference was statistically significant(P < 0.05);There was an upward trend in rSO2 in 24 hours after admission about group B,which may be related to ischemia reperfusion injury,Mild hypothermia therapy can reduce the oxygen consumption(oxygen content),improve the cerebral circulation and metabolism and the prognosis;3.both of the two groups of newborns,who admitted to hospital within 12 hours,have downward trend,however,in the mild hypothermia group,the rSO2 decreased faster and lower than group in conventional symptomatic treament,The decrease of oxygen consumption of brain cells suggests that ATP energy consumption is reduced,that is better protection against brain cells;the brain oxygen in the mild hypothermia group was lower than that in the conventional treatment group,and the difference was statistically significant during the mild hypothermia treatment.4.The aEEG scores of different time-window and mild hypothermia were higher than those ofconventional treatment group,The differences were statistically significant,which proved that mild hypothermia therapy can improve the prognosis of HIE better than conventional treatment.5.The NSE values of the HIE who were admitted to the hospital within 6 hours after treatment were lower than those in the conventional treatment group,and the difference was statistically significant,the number of nerve cell death was lower in mild hypothermia group,that is better to reduce brain cell damage,maybe the prognosis in HIE will be better;The NSE values of the HIE who were admitted to the hospital within 12 hours after treatment were lower than those in the conventional treatment group,but the difference was not statistically significant(P > 0.05),it remains to be seen whether the use of mild hypothermia after 6 hours is more effective than conventional therapy in reducing the number of nerve cell death.Conclusions: The mild hypothermia therapy in different time-window can reduce the oxygen consumption and metabolism of HIE brain cells,and give the protection of the brain cells,in particular,the effect of mild hypothermia treatment within 6 hours is more obvious,so the sooner the treatment will be better.The mild hypothermia treatment Should be used as early as possible,to reduce reperfusion injury as far as possible;Near infrared spectroscopy(NIRS)can be used to monitor the rSO2 in a noninvasive,real-time and bedside manner,which provide a direct and effective basis for improving the oxygen consumption of braintissue in mild hypothermia,so NIRS Should be popularized in clinical.The combination of rSO2,NSE and aEEG can improve the prognosis of newborns with HIE.