Hidaka A, Suzuki Y, Komatani M, Ikeda H, Kitanaka T, Sugawa T
Nihon Sanka Fujinka Gakkai Zasshi. 1986 Oct;38(10):1754-62.
Pregnant rabbits were subjected to inhalation of different gases, and the changes in placental blood flow (PBF), fetal heart rate (HR), and fetal cerebral blood flow (CBF) associated with the changes in maternal blood gas levels were studied. The results are given below. In maternal hyperoxia, maternal blood pressure (BP) was not much influenced and PBF remained unchanged or was slightly decreased when the PCO2 level was not varied or when it was lowered. In contrast, not only maternal BP but also PBF was increased when the PCO2 level was elevated. In the absence of a conspicuous increase in PCO2, neither fetal HR nor CBF varied, regardless of PBF. Both maternal BP and PBF were increased in mild to moderate maternal hypoxia (PO2 greater than 40 mmHg) and decreased in severe hypoxia (PO2 less than 30 mmHg). The decreasing trend of fetal HR or CBF was strengthened as maternal hypoxia was intensified. An obvious decrease in either parameter was observed in severe maternal hypoxia (PO2 less than 30 mmHg). Fetal HR and CBF were well maintained. in hypoxic dams with increased PBF as compared with those with unchanged or decreased PBF. The higher the PCO2 level or the lower the pH value, the more was fetal bradycardia that was apt to occur, even in a mildly hypoxic state.
将怀孕兔子暴露于不同气体中，研究了与母体血气水平变化相关的胎盘血流量（PBF）、胎儿心率（HR）和胎儿脑血流量（CBF）的变化。结果如下。在母体高氧状态下，当PCO2水平不变或降低时，母体血压（BP）受影响不大，PBF保持不变或略有下降。相反，当PCO2水平升高时，不仅母体BP升高，PBF也升高。在PCO2没有明显升高的情况下，无论PBF如何，胎儿HR和CBF均无变化。在轻度至中度母体缺氧（PO2大于40 mmHg）时，母体BP和PBF均升高，而在严重缺氧（PO2小于30 mmHg）时则降低。随着母体缺氧加剧，胎儿HR或CBF的下降趋势增强。在严重母体缺氧（PO2小于30 mmHg）时，观察到这两个参数均明显下降。与PBF不变或降低的缺氧母兔相比，PBF增加的缺氧母兔的胎儿HR和CBF得到了较好的维持。即使在轻度缺氧状态下，PCO2水平越高或pH值越低，胎儿心动过缓越容易发生。
