Morales-Roselló José, Hervás-Marín David, Perales-Marín Alfredo
Servicio de Obstetricia y Ginecología, Hospital Universitario y Politécnico La Fe , Valencia , Spain and.
J Matern Fetal Neonatal Med. 2014 Feb;27(3):283-90. doi: 10.3109/14767058.2013.814634. Epub 2013 Jul 16.
To determine the existence of Doppler changes in the fetal vertebral, middle cerebral and umbilical arteries prior to term labor.
Five hundred and twenty eight Doppler examinations of the vertebral (VA), middle cerebral (MCA) and umbilical (UA) arteries resistance indices (RI) were performed between 37 and 41 weeks gestation. For each artery, values were converted into multiples of the median (MoM) and were divided into four groups according to the interval to labor and compared using Kruskal-Wallis tests. Subsequently, values were plotted in scattergrams and linear regressions and 95% confidence intervals were calculated. Finally, using multivariate analysis and model averaging, the importance and interrelationship of Doppler measurements in the explanation of the interval to labor was evaluated.
Univariate and multivariate analysis confirmed that, independently of gestational age, fetuses examined close to labor presented more intense Doppler changes in the cerebral arteries with a significant reduction of the VA RI and MCA RI. This reduction was larger in the MCA. No significant changes were detected in the UA.
Before the onset of term labor, the fetal cerebral flow presents an additional reduction of impedance, which is more intense in the MCA system.
确定足月分娩前胎儿椎动脉、大脑中动脉和脐动脉的多普勒变化情况。
在妊娠37至41周期间，对椎动脉（VA）、大脑中动脉（MCA）和脐动脉（UA）进行了528次多普勒检查，测量其阻力指数（RI）。对于每条动脉，将测量值转换为中位数倍数（MoM），并根据距分娩的时间间隔分为四组，采用Kruskal-Wallis检验进行比较。随后，将测量值绘制在散点图和线性回归图中，并计算95%置信区间。最后，使用多变量分析和模型平均法，评估多普勒测量值在解释距分娩时间间隔方面的重要性和相互关系。
单变量和多变量分析均证实，与胎龄无关，接近分娩时检查的胎儿大脑动脉的多普勒变化更为明显，椎动脉阻力指数（VA RI）和大脑中动脉阻力指数（MCA RI）显著降低。大脑中动脉的降低更为明显。脐动脉未检测到显著变化。
在足月分娩开始前，胎儿脑血流阻抗进一步降低，大脑中动脉系统更为明显。
