多普勒超声检测肾血流评估窒息新生儿早期肾损害的价值

Evaluation of early renal damage of asphyxiated neonates by Doppler ultrasonograghy

目的探讨多普勒超声检测肾血流评估窒息新生儿早期。肾损害的价值。方法检测足月窒息新生儿75例（Apgar评分≤7分）和正常足月非窒息新生儿（对照组）20例生后第1、3、7天的血清尿素氮、肌酐、尿微量蛋白系列、尿酶，分析多普勒超声仪测量收缩期最大分流指数（Vmax）、舒张期最低流速（Vmin）并计算阻力指数（resistant index，RI），分析两组各指标改变情况。组间比较采用方差分析。结果（1）对照组新生儿第1天肾血流Vmax为（45．66±2．43）m／s，Vmin为（13．61±1．47）m／s，RI为0．69±0．09，生后第1、3、7天间差异无统计学意义。（2）轻度窒息组新生儿生后第1天血清肌酐为（49．81±19．72）μmol／L，尿微量白蛋白为（4．13±2．49）mg／L、转铁蛋白为（1．12±0．56）mg／L，N-乙酰-β-D-葡萄糖苷酶为（10．72±2．79）U／（mmol·Cr），αl微球蛋白为（2．27±1．23）mg／L，均较对照组显著升高（P〈0．05）。（3）轻度窒息组新生儿生后第1天Vmax为（42．84±2．19）m／s、Vmin为（8．27±1．98）m／s，低于对照组；RI为0．79±0．04，高于对照组（P〈0．05）；重度窒息组的肾血流指数改变比轻度窒息组更明显。（4）Vmax和Vmin与血清尿素氮、肌酐，尿微量白蛋白、转铁蛋白及N-乙酰-β-D-葡萄糖苷酶、α1微球蛋白呈负相关，RI与上述指标呈正相关。（5）生后第1天肾血流指标的阳性率显著高于尿微量蛋白系列和尿酶指标。结论多普勒超声检测肾血流是一种无创、可重复性好、操作简单、结果快速的检测手段，对于窒息新生儿早期的肾功能评价具有良好的指导价值。

Objective To evaluate early renal damage of asphyxiated neonates by measurement of renal blood flow with Doppler ultrasonography. Methods The asphyxia group included 75 neonates （Apgar score ≤7）, non-asphyxia group included 20 term normal neonates. Serum ereatinine （Cr）, blood urea nitrogen （BUN）, a series of urine microprotein, urine enzymes, urine routine and renal blood flow were determined at the first, third and 7th day after birth. Results （1） On the first day, in the non-asphyxiate neonates group, the average Vmax of renal blood flow was （45.66±2. 43） m/s, the average Vmin was （13.61±1.47） m/s, RI was 0. 69d=0. 09. No indexes changed during the following 7 days. （2） Gromerulus markers of asphyxia group, including serum Cr, BUN, nurine microalbumin and transferrin, were higher than those of non-asphyxia group. In the asphyxia group, the renal tubule markers [urinary N-acetyl-β-D-glucosaminidase （NAG）, al microglubin （α1MG）] were higher than those of non-asphyxia group. （3） The renal blood flow values （Vmax, Vmin） of asphyxia group were lower than those of non-asphyxia group, while RI was higher. （4）The Vmax and Vmin were negatively related to Cr, BUN, urine microprotein, urine NAG and α1MG, RI was positively related to those markers. （5） On the first day after birth, the abnormal rate of renal blood flow indexes was higher than that of urine indexes. Conclusions The ultrasonic examination of neonate renal blood flow is a convenient, safe, fast, sensitive and repeatable method for evaluation of kidney dysfunction in asphyxiated neonates.