Sameshima H, Ikenoue T, Kamitomo M, Sakamoto H
Department of Obstetrics and Gynecology, Kagoshima City Hospital, Japan.
J Soc Gynecol Investig. 1996 Sep-Oct;3(5):235-40. doi: 10.1016/s1071-5576(96)00021-4.
The effects of magnesium sulfate on fetal heart rate (FHR) response during acute hypoxemia in goats were investigated.
The FHR responses due to hypoxemia during magnesium sulfate infusion (Mg study) were compared with those during vehicle infusion (controls) in six chronically instrumented goat fetuses at 125-130 days' gestation.
Four-hour infusions of magnesium sulfate significantly increased fetal plasma concentrations of magnesium from 2.3 to 6.5 mg/dL. During the hypoxemic period, the fetal arterial oxygen pressure was significantly decreased from 29.0 +/- 2.5 to 14.6 +/- 2.6 torr in the controls, and from 28.9 +/- 3.9 to 13.7 +/- 4.7 torr during the Mg study. Neither arterial carbon dioxide pressure nor pH was significantly altered. In the controls, FHR was significantly decreased by hypoxemia, accompanied by increases in variability. In the Mg study, FHR was not significantly decreased by hypoxemia. Acute hypoxemia also increased the FHR variability during magnesium infusion, which was significantly reduced compared with those in the control population.
Magnesium sulfate masks FHR-slowing responses during acute hypoxemia in fetal goats.
研究硫酸镁对山羊急性低氧血症期间胎儿心率（FHR）反应的影响。
在妊娠125 - 130天的6只长期植入仪器的山羊胎儿中，将输注硫酸镁期间（镁研究组）因低氧血症引起的FHR反应与输注赋形剂期间（对照组）的反应进行比较。
输注4小时硫酸镁后，胎儿血浆镁浓度从2.3毫克/分升显著增加至6.5毫克/分升。在低氧血症期间，对照组胎儿动脉血氧分压从29.0±2.5降至14.6±2.6托，镁研究组从28.9±3.9降至13.7±4.7托。动脉二氧化碳分压和pH值均无显著变化。在对照组中，低氧血症使FHR显著降低，并伴有变异性增加。在镁研究组中，低氧血症未使FHR显著降低。急性低氧血症在输注硫酸镁期间也增加了FHR变异性，与对照组相比显著降低。
硫酸镁掩盖了山羊胎儿急性低氧血症期间FHR减慢反应。
