脐带绕颈对胎儿脐静脉血流的影响

The Umbilical Venous Flow Slowdown under the Condition of Nuchal Umbilical Cord

目的探讨妊娠晚期脐带绕颈对胎儿脐静脉血流的影响.方法随机选择孕龄36～40周,脐带绕颈但尚无产兆的孕妇65例,观察在无胎动、无胎儿呼吸运动时脐静脉血流速度并记录.结果有脐带绕颈的胎儿,脐静脉血流速度明显低于对照组(P＜0.05).结论无产兆的胎儿处于静息状态时,脐带绕颈对胎儿脐静脉血流速度有一定影响.其原因是脐带缠绕形成局部环状管道,血流的离心力增加了系统的阻力,导致动能减少,血流速度下降.

Objective The study was to detect the umbilical venous blood flow under the condition of nuchal twisted umbilical cord in late gestation.Methods Sixty five pregnant women, in which nuchal cord were found from 36 to 40 weeks gestation, were randomly choosed to have a routine ultrasound examination. Doppler spectra of umbilical vein were acquired and recorded at the fetus abdominal end under a resting fetus. Results The umbilical venous flow velocityies of the nuchal cords were significantly slow that that of the control group. Conclusion The umbilical venous flow velocity could slow down under the nuchal cord condition and a resting fetus at the late pregnancy. The reasons for this could be the more resistance and eccentric gravity produced from an encircling blood flow movement.