Factors affecting human placental transfer of anesthesia-related drugs.

胎泊酚在人双子叶离体胎盘移植中的应用。本研究采用双融合人胎盘腔（单通道模式）研究子宫和脐血流量及白蛋白浓度（蛋白结合）对异丙酚胎盘转移的影响。根据不同流速或母体和胎儿灌注物白蛋白浓度的胎盘清除率来评估胎盘转移。在母体灌注液中加入安替比林作为对照。结果表明：(1)在母体白蛋白水平不变的情况下，随着胎儿灌注液中白蛋白浓度的增加，胎儿灌注液中异丙酚浓度及其清除率增加，而未结合的异丙酚浓度和安替比林清除率不变。(2)随着母体灌注液白蛋白浓度的升高，胎儿流出物异丙酚浓度和胎盘清除率降低。(3)随着母体血流量的增加，胎儿流出液中丙泊酚浓度升高，丙泊酚和安替比林的清除率均升高（清除率不变）。(4)随着胎儿血流量的增加，胎儿流出液中丙泊酚浓度不变，丙泊酚清除率呈流量依赖性增加，而安替比林清除率呈上限。(5)异丙酚对胎盘组织有明显的分割作用，胎盘起凝血剂的作用。综上所述，我们的模型使用清除率参数能够准确表征药物的胎盘转移，而传统的母胎血浓度测定（F/M比）受子宫血流量、脐带血流量以及母脐血蛋白结合的影响极大

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