Placental Interchange. Ii. Comparison of the Total Base Concentration of the Fetal and Maternal Blood at Parturition

Abstract

Although the literature on the permeability of the placenta to many substances either of a metabolic or foreign origin is extensive, there is a paucity of data on comparisons of maternal and infant total base. In 1920 Stander and Tyler (1) reported identical values for the ash of maternal and fetal plasma, while Levy-Solal, Dalsace, and Gutman (2) in 1934 reported the maternal and fetal plasma ash to be 7.97 and 9.25 grams per liter respectively. Eastman, Geiling, and De Lawder (3) found the total serum base of fetal and maternal serum to be low and stated that the normal adult total base was about 154.0 m.eq., while that of fetal blood was about 148 m.eq.In the present study, the total base was determined simultaneously on samples of maternal venous, umbilical arterial, and umbilical venous plasma from blood obtained at the time of delivery. METHODSThe subjects of this study were 30 parturient women and their respective normal appearing, newborn children, No discriminations as to age, race, previous history of the mother or the weight or sex of the infant were made. However, infants born in a debilitated condition and their respective mothers were not among those on whom data is reported here. As has been noted in a previous paper (4), values for maternal blood are regarded as approximating the fasting level because little food is ordinarily consumed during labor.Collection of blood. At delivery of the infant, the umbilical cord was cut and blood collected from the umbilical arteries and the umbilical vein. The blood was received into a centrifuge tube to which 10 mgm. of heparin were added to prevent clotting. In only a very few instances was there clot formation. Shortly after collection of fetal blood, blood was withdrawn without stasis from a maternal arm vein, and treated to prevent clotting as described above. All blood collections were generally completed within about 5 minutes. Centrifugalization for 20 minutes at moderate speed was then carried out, and the hematocrit determined. All volumetric apparatus employed in the total base analysis was calibrated by the weight method before beginning this study. In order to measure accurately 02 cc. of plasma, 1 cc. of plasma was diluted to 10 cc., and 2 cc. aliquots of this solution were used in each analysis. Each determination was made in duplicate and 2 blanks were run with each dialysis, 8 cells being run at a time.Determination of total base. The rapid and efficient electrodialysis method for total base determination developed not long ago by Keys (5) was employed with gratifying results. The mercury employed was purified by vacuum distillation. Checks indicated that stock distilled water was as satisfactory as that obtained by distillation with phosphoric acid. Using as control a salt solution containing 130.5 m.eq. of sodium and 4.5 m.eq. of potassium, the mean of 7 consecutive determinations of total base was found to be 134.6 ± 0.7 m.eq. The deviation of the mean from the expected value was -0.3 per cent. Since plasma solutions are far more complex ...

The Placental Transmission of Protective Antibodies Against Whooping Cough

“…Child. 59:61 (Jan.) 1936. Gordon, J. E., and Janney, J. and his colleagues,18 however, have presented evidence that allergenic antigens can traverse the normal placentral membrane and actively induce antibody produc¬ tion.…”