Factors affecting human placental transfer of anesthesia-related drugs.

异丙酚在体外人双融合子叶中的胎盘转移。采用人双融合子叶(单次通过模式)，研究子宫和脐血流量以及白蛋白浓度(蛋白结合)对异丙酚胎盘转移的影响。胎盘移植根据不同流速下的胎盘清晰度或母体和胎儿灌流液中的白蛋白浓度进行评估。在母体灌流液中加入安替比林作为参照物。结果(L)在母体白蛋白水平不变的情况下，随着胎儿灌流液中白蛋白浓度的增加，胎儿灌流液中丙泊酚浓度及其清除量增加，而游离异丙酚浓度和安替比林清除量无明显变化。(2)随着母体灌流液中白蛋白浓度的增加，胎儿流出液中丙泊酚浓度和胎盘清除量均呈下降趋势。(3)随着母体血流量的增加，异丙酚浓度增加，而异丙酚和安替比林清除量均增加(清除率不变)。(4)随着胎儿血流量的增加，异丙酚在胎盘外流中的浓度不变，清除量呈流量依赖性增加，而安替比林清除量呈峰值。(5)异丙酚对胎盘组织有明显的分割作用，胎盘是一个凝聚体。综上所述，我们的模型可以用清除量参数准确地表示胎盘药物的转运，而传统的母婴血药浓度(F/M比)的测定受子宫血流量、脐血流量以及母血和脐血中蛋白质结合的影响很大

Placental transfer of porpofol in human dually per fused cotyledon in vitro.We investigated the effects of uterine and umbilical blood flow and albumin concentration (protein binding) on the placental transfer ofpropofol by using the dually per fused human placental cityledon(single pass mode). Placental transfer was evaluated on the basis ofplacental clearaces at various flow rates or albumin concentrations of maternal and fetal perfusates. Antipyrine was added to the maternal perfusate as a reference. As results, (l) With increasing albumin concentrations of the fetal perfusate at constant maternal albumin level, propofol concentrations of fetal perfusate and its clearance were increased while both unbound propofol concentration and antipyrine clearance were unchaged. (2) With increasing albumin concentrations of maternal perfusate, propofol concentration of fetal outflow and placental clearance were decreased. (3) With increasing maternal blood flow, the propofol concentration of fetal out flow was increased while both clearance ofpropofol and antipyrine were increased (clearance ratio was constant). (4) With increasing fetal blood flow, the propofol concentration of fetal out flow was unchanged while clearance of propofol was flow-dependency increased but clearance of antipyrine showed ceiling.(5) Propofol significantly partitioned to placental tissues and the placenta would act as a condenser.In summary, our model could exactly denote the placental transfer of drug using the parameter of clearance while traditional determination of maternal and fetal blood concentration (F/M ratio) was extremely influenced with uterine blood flow, umbilival blood flow, and protein binding in maternal and umbilical blood