多普勒超声诊断胎儿宫内缺氧的大样本分析

Large sample analysis of Doppler ultrasound in diagnosing fetal intrauterine hypoxia

目的探讨多普勒超声诊断孕晚期不同孕周胎儿宫内缺氧的临床应用价值。方法选取2016年1—12月在我院行产前检查并于28~41+6周住院分娩的无宫内缺氧新生儿1 017例(正常组,包括28~31+6周347例、32~36+6周360例、37~41+6周310例),宫内缺氧新生儿218例(缺氧组,包括28~31+6周47例、32~36+6周82例、37~41+6周89例),均于产前应用彩色多普勒超声检测胎儿脐动脉(UA)、大脑中动脉(MCA)血流动力学参数,包括阻力指数(RI)、搏动指数(PI)、收缩期峰值流速舒张期流速比值(S/D)。结果 (1)孕晚期无宫内缺氧胎儿UA各血流参数均随孕周的升高而降低,以UA-S/D>3.0为标准诊断32~36+6周及37~41+6周胎儿宫内缺氧的特异度分别为94%、99%,但诊断28~31+6周胎儿宫内缺氧的特异度仅67%。(2)孕晚期无宫内缺氧胎儿MCA各血流参数随孕周的升高而降低,孕足月显著降低。以MCA-RI<0.6、PI<1.6、S/D<4.0为标准诊断28~31+6周及32~36+6周胎儿宫内缺氧的特异度分别为99%、98%,但诊断37~41+6周胎儿宫内缺氧的特异度仅24%。(3)孕晚期胎儿发生宫内缺氧时UA各项血流参数显著升高,MCA各项血流参数显著降低。以UA-S/D>3.28为标准诊断28~31+6周胎儿宫内缺氧的约登指数升至0.76。MCA各项血流参数对孕足月胎儿宫内缺氧不具诊断意义。结论孕晚期不同孕周胎儿UA及MCA各项血流动力学指标有其独特的变化规律,应联合诊断以提高胎儿宫内缺氧的诊断准确率。

Objective To evaluate the clinical value of Doppler ultrasonography in the diagnosis of fetal intrauterine hypoxia in different gestational weeks of late pregnancy.Methods From January 2016 to December 2016,1 017 neonates without intrauterine hypoxia(normal group,including 347 cases of 28-31+6 weeks,360 cases of 32-36+6 weeks,310 cases of 37-41+6 weeks)and 218 neonates with intrauterine hypoxia(hypoxia group,including 47 cases of 28-31+6 weeks,82 cases of 32-36+6 weeks,89 cases of 37-41+6 weeks)were subjected to a prenatal examination and hospital delivery at 28-41+6 weeks in our hospital.The colour Doppler ultrasound was used to detect hemodynamic index of umbilical artery(UA)and middle ce.rebral artery(MCA),including resistance index(RI),pulsation index(PI)and systolic peak velocity diastolic velocity ratio(S/D)in the prenatal stage in all subjects.Results(1)The UA blood flow parameters decreased with the increase of gestation.al age in late pregnancy without intrauterine anoxia.With UA-S/D>3.0 as diagnostic criteria,the fetal hypoxia specificities were 94%and 99%for 32-36+6 weeks and 37-41+6 weeks,but the fetal hypoxia specificity was 67%for the diagnosis of 28-31+6 weeks.(2)The blood flow parameters of MCA decreased with the increase of gestational age,and which was decreased significantly over the full pregnancy term in late pregnancy without intrauterine anoxia.MCA-RI<0.6,PI<1.6 and S/D<4.0 were used as criteria for the diagnosis of intrauterine fetal hypoxia,the fetal hypoxia specificities were 99%and 98%in 28-31+6 weeks and 32-36+6 weeks.However,the specificity of fetal hypoxia was only 24%in 37-41+6 weeks.(3)In the late preg.nancy,UA blood flow parameters were significantly increased,and the blood flow parameters of MCA were significantly re.duced in intrauterine hypoxia fetal.The UA-S/D>3.28 was used as the standard to diagnose the intrauterine hypoxia in 28-31+6 weeks,Youden index increased to 0.76.The MCA index showed no diagnostic significance for intrauterine hypoxia in full-term pregnancy.Conclusion The hemodynamic parameters of UA and MCA have their own changing rules in late pregnancy at different gestational weeks,which should be combined with the diagnosis to improve the diagnostic accuracy of intrauterine hypoxia.