Li H, Gudmundsson S, Olofsson P
Departments of Obstetrics and Gynecology, Malmö University Hospital, Lund University, Malmö, Sweden.
Ultrasound Obstet Gynecol. 2003 Dec;22(6):578-85. doi: 10.1002/uog.921.
No quantitative or qualitative Doppler velocimetry classification of vascular flow resistance covering all stages of forward and reversed flows exists. The objective of this study was to characterize uterine artery (UtA) flow velocity waveforms (FVWs) obtained during an oxytocin challenge test (OCT) and compare them to FVWs in spontaneous normal labor.
Uterine artery Doppler velocimetry was performed during and between uterine contractions in 61 high-risk pregnancies subjected to an OCT and in 20 normal pregnancies undergoing spontaneous labor. FVWs were classified relative to the presence of forward/absent/reversed flow during systole and diastole, and the time-averaged flow velocity over the heart cycle.
Eleven different FVW classes were identified. No relationship between FVWs recorded during uterine inertia and contractions was found (P >/= 0.2). In both groups, only forward FVWs were recorded between contractions, whereas during contractions flow reversal was more common in the OCT group (P </= 0.002). In cases of predominantly reversed flow, a reciprocal relationship to FVW classes recorded in the contralateral artery was found.
UtA FVW patterns recorded during uterine contractions were not predicted by flow patterns recorded during uterine inertia. Reversal of flow direction was more common during oxytocin-induced uterine contractions than during spontaneous contractions. In cases of predominantly reversed flow, domains of the uterus may be supplied by blood from the contralateral UtA. These observations give new insights into the circulatory dynamics of the uterus during labor, and also point to a possible vasoconstrictory effect in the UtAs of oxytocin at high concentrations.
目前尚无涵盖正向和反向血流所有阶段的血管血流阻力的定量或定性多普勒测速分类方法。本研究的目的是对催产素激惹试验（OCT）期间获得的子宫动脉（UtA）血流速度波形（FVW）进行特征描述，并将其与自然正常分娩时的FVW进行比较。
对61例接受OCT的高危妊娠和20例自然分娩的正常妊娠在子宫收缩期间及收缩间歇期进行子宫动脉多普勒测速。根据收缩期和舒张期正向/无/反向血流的存在情况以及心动周期的时间平均流速对FVW进行分类。
识别出11种不同的FVW类别。未发现子宫静止期和收缩期记录的FVW之间存在相关性（P≥0.2）。在两组中，收缩间歇期仅记录到正向FVW，而在收缩期，OCT组血流反向更为常见（P≤0.002）。在主要为反向血流的情况下，发现与对侧动脉记录的FVW类别呈反比关系。
子宫收缩期记录的UtA FVW模式无法通过子宫静止期记录的血流模式预测。催产素诱导的子宫收缩期间血流方向反转比自然收缩期间更常见。在主要为反向血流的情况下，子宫的某些区域可能由对侧UtA供血。这些观察结果为分娩期间子宫的循环动力学提供了新的见解，也指出了高浓度催产素对UtA可能存在的血管收缩作用。
