硬膜外阻滞在剖宫产时对胎儿脐血流的影响

Effect of umbilical blood flow during cesarean section under epidnral anesthesia

目的 观察剖宫产术硬膜外阻滞时对胎儿脐血流的影响。方法 采用多普勒超声仪,探头频率3.5MHz。麻醉前测脐静脉(U_V)脐动脉(U_A)直径。记录U_A收缩期峰值速度(Vmax)、舒张期最低速度(Vmin)、平均速度(Vmean)。算出Vmax及Vmin之比(S/D)、搏动指数(PI)及阻力指数(RI)。脉冲多普勒取样线与脐动脉长轴夹角θ≤20度。产妇硬膜外阻滞待麻醉平面达T_(3～9)后(约10min)再监测上述各项参数。结果 麻醉后U_V及U_A血流量明显高于麻醉前(P<0.05)。S/D、PI及RI麻醉前后无明显变化(P>0.05)。结论 硬膜外阻滞后可增加脐血流而不增加脐血管阻力,对胎儿血供是有利的。

Objective Using colour Doppler to determine the effect of epidural anesthesia on the umbilical blood flow during cesarean section. Methods Using colour Doppler technique measure the diameter of umbilical venous and umbilical arteries, maximum systolic velocity( Vmax), diastolic minimum velocity( Vmin)and its mean velocity(Vmean) were record. The ratio of Vmax to Vmin(S/ D), pulsatility index(PI)and resistance index(RI) were measured before epidural anesthesia. Eighteen patients were injected 20ml mixed liquid of 1.33% lidocaine and 0.17% dicaine through I2-3 epidu-rally with the patient in the left lateral position. Uv, UA. S/D, PI, RIwere recorded again after 10 minutes. Results Uv and UA increased significantly anesthesia comparing with those before anesthesia (P<0.05).There is no changes in the S/D,PI and RI(P>0.05).Conclusion The methods of the epidural anesthsia increase umbilical blood flow but do not change the resistance of umbilical vascular. It is benefitial to fatals.