窒息早产儿脑血流变化及其与新生儿脑损伤的关系

Changes of cerebral blood flow in premature infants with asphyxia and its relationship with neonatal brain injury

目的分析窒息早产儿脑血流变化及其与新生儿脑损伤的关系。方法将2018年1月至2019年6月在西北妇女儿童医院产科出生的62例窒息早产儿分为轻度窒息组41例和重度窒息组21例,选取同期无窒息史的30例早产儿作为对照组。出生后24 h、3 d、7 d时使用经颅彩色多普勒检测并比较三组早产儿的大脑中动脉(MCA)血流动力学参数[收缩期峰值血流速度(Vs)、舒张末期血流速度(Vd)、平均血流速度(Vm)、阻力指数(RI)],并进行头颅超声判定是否发生脑损伤。对脑损伤、窒息程度与24 h时的MCA血流动力学参数相关性进行Spearmen秩相关分析。结果出生后24 h时,重度窒息组早产儿的Vs、Vd和Vm分别为(28.56±6.86)cm/s、(6.09±1.57)cm/s、(12.49±3.23)cm/s,明显低于轻度窒息组的(34.42±5.22)cm/s、(8.43±2.11)cm/s、(16.03±3.87)cm/s,也明显低于对照组的(37.04±4.56)cm/s、(10.56±2.64)cm/s、(19.22±4.80)cm/s。重度窒息组早产儿的RI为(0.81±0.12),明显高于轻度窒息组的(0.75±0.09),也高于对照组的(0.70±0.10),差异均有统计学意义(P<0.05);三组早产儿脑损伤发生率由高到低依次为重度窒息组(52.38%)、轻度窒息组(19.51%)、对照组(3.33%),差异有统计学意义(P<0.05);Vs与脑损伤、窒息程度呈负相关(r=-0.389、0.442,P<0.05),而RI与脑损伤、窒息程度呈正相关(r=0.287、0.415,P<0.05),Vm与窒息程度呈负相关(r=-0.393,P<0.05),Vd与脑损伤、窒息程度无明显相关性(r=-0.124、-0.187,P>0.05)。结论窒息对早产儿脑血流变化有明显影响,脑血流越慢、阻力指数越高,早产儿窒息越严重,对预测脑损伤的发生有重要价值。

Objective To analyze the changes of cerebral blood flow in premature infants with asphyxia and its relationship with neonatal brain injury.Methods The 62 premature infants with asphyxia born in the Department of Obstetrics at Northwest Women and Children's Hospital from January 2018 to June 2019 were divided into a mild asphyxia group(41 cases)and a severe asphyxia group(21 cases),and 30 premature infants without history of asphyxia during the same period were selected as the control group.Transcranial color Doppler was used to detect and compare the hemodynamic parameters of middle cerebral arteries(MCA),including peak systolic blood flow velocity(Vs),end-diastolic blood flow velocity(Vd),mean blood flow velocity(Vm),and resistance index(RI)in the three groups of premature infants at 24 h,3 d and 7 d after birth.Cranial ultrasound was performed to determine whether brain injury had occurred.The correlation between brain injury,asphyxia degree and the MCA hemodynamic parameters at 24 hours was analyzed by Spearmen rank correlation.Results At 24 h after birth,the Vs,Vd,and Vm of premature infants in the severe asphyxia group were significantly lower than those in the mild asphyxia group,i.e.Vs(28.56±6.86)cm/s vs(34.42±5.22)cm/s,P<0.05;Vd(6.09±1.57)cm/s vs(8.43±2.11)cm/s,P<0.05;and Vm(12.49±3.23)cm/s vs(16.03±3.87)cm/s,P<0.05,and were also significantly lower than those in the control group:Vs(37.04±4.56)cm/s,Vd(10.56±2.64)cm/s,and Vm(19.22±4.80)cm/s;all P<0.05.The RI of premature infants in the severe asphyxia group(0.81±0.12)was significantly higher than that of the mild asphyxia group(0.75±0.09)and also higher than that of the control group(0.70±0.10),and all differences were statistically significant(P<0.05).The incidence of brain injury in the three groups of premature infants in descending order was the severe asphyxia group(52.38%),the mild asphyxia group(19.51%),and the control group(3.33%),and all differences were statistically significant(P<0.05).Vs was negatively correlated with brain injury and asphyxia degree(r=-0.389,0.442,P<0.05),while RI was positively correlated with brain injury and asphyxia degree(r=0.287,0.415,P<0.05).Vm was negatively correlated with the degree of asphyxia(r=-0.393,P<0.05),while Vd had no significant correlation with the brain injury and asphyxia degree(r=-0.124,-0.187,P>0.05).Conclusion Asphyxia has a significant effect on the changes of cerebral blood flow in premature infants.When the cerebral blood flow is slower and the resistance index is higher,the asphyxia of premature infants is more severe,which is of great value in predicting the occurrence of brain injury.