Simultaneous investigations of maternal cardiac output and fetal blood flow during hypervolemic hemodilution in preeclampsia — preliminary observations

In pre-eclampsia hemodynamic alterations are characterized by a lack of plasma volume expansion and a raised peripheral vascular resistance. For the compensation of plasma volume deficit and to restitute blood fluidity the therapeutic use of plasma volume expanders (f.e. low molecular dextran) is recommended. Several groups (Goodlin et al., Cloeren et al., Heilmann et al., Seghal et al., Schröck) have demonstrated benefitial effects on fetal status and development in the course of hypervolemic hemodilution in preeclampsia. This therapeutic procedure presumes the continuous surveillance of maternal hemodynamics to early recognize heart insufficiency or fluid overload in the lungs. We use the noninvasive thoracic impedance cardiography for continuous monitoring of maternal heart performance. The effect of hypervolemic hemodilution on fetal circulation has not been quantitatively investigated yet. Meanwhile pulsed doppler ultrasonography offers the possibility of estimating quantitative changes on fetal blood flow. We used both noninvasive techniques--thoracic impedance cardiography and pulsed doppler imaging system--for the simultaneous evaluation of maternal and fetal hemodynamic parameters during hypervolemic hemodilution. This preliminary report summarizes the investigations in 5 patients with pre-eclampsia (mean arterial blood pressure greater than or equal to 103.3 mm Hg, hemoconcentration with elevated hematocrit levels greater than or equal to 38%). The patients received an infusion of 500 ml dextran 40 over a period of exactly 60 minutes. The simultaneous measurements of maternal and fetal cardiovascular parameters were performed in 15-minutes intervals during dextran application and 15 minutes (p 15), 30 minutes (p 30) and 60 minutes (p 60) after the end of infusion.(ABSTRACT TRUNCATED AT 250 WORDS)