超声观察正常胎儿肾动脉的血流动力学参数及其临床价值

目的以彩色多普勒超声观察不同孕周胎儿肾动脉(RA)收缩期峰值血流速度(Vmax)、舒张期最低血流速度(Vmin)及搏动指数(PI)、阻力指数(RI),确定其正常参考值,分析其与孕龄的相关性。方法从接受常规产前超声检查的18～40周孕妇中选取符合条件的2627名进入样本库,测量胎儿肾动脉Vmax、Vmin和PI、RI,最后按孕龄分组,并进行统计学处理。结果胎儿左、右侧肾动脉血流Vmax(r=0.75,0.75)、Vmin(r=0.62,0.60)与孕龄呈正相关(P均<0.05),RI、PI随孕龄增长而呈缓慢下降趋势,仅在妊娠末期略有回升;胎儿左、右肾各血流参数测值间差异无统计学意义(P>0.05)。结论胎儿肾动脉血流速度与孕龄呈正相关,而肾动脉RI、PI随孕龄变化幅度很小。胎儿肾动脉血流监测可作为预测和评估胎儿有无宫内缺氧的方法之一。

Ultrasonic measurement and clinical value of kinetic parameters of normal fetal renal artery blood flow

Objective To observe the normal scope of reference values of peak blood flow velocity(Vmax) of fetal renal artery(RA) in different gestational ages,end-diastolic blood flow velocity(Vmin) and pulsatility index(PI) and resistance index(RI) with color Doppler ultrasound,and to analyze its correlativity with gestational age.Methods Totally 2627 eligible pregnant women of 18—40 gestational weeks who received regular prenatal ultrasonic examination were enrolled.Parameters of fetal RA blood flow were measured,including Vmax,Vmin and PI as well as RI,and their relationship with gestational age was statistically analyzed.Results Vmax(r=0.75,0.75)and Vmin(r=0.62,0.60) of fetal renal artery flow had positive relation(all P<0.05) with gestational age.RI and PI showed a slow downward trend,only had a slight rising during the late period of pregnancy.There was no obvious statistical difference among measured values of all blood flow parameters in both left and right kidneys of fetus(P>0.05).Conclusion Fetal RA blood flow velocity is positively correlated with gestational age.There is very small variation of kidney artery RI and PI along with gestational age.Detection of fetal renal artery flow can be regarded as indexes for predicting and assessing the existence of intrauterine fetus hypoxia.