Analysis of the inter‐ and intravillous placental blood circulation in high‐risk pregnancies before and after the hemodilution therapy using the colour‐angio‐mode

Abstract

Objective: The aim of the study was to examine the efficiency of a hemodilution (HD) therapy on the inter‐ and intravillous placental blood circulation in high‐risk pregnancies by applying the colour‐angio‐mode (CAM).

Patients and methods: 24 patients were examined who had fetal growth retardation and/or pathological Doppler results. In all cases the hematocrit was >36%. The patients were given 500 ml Ringer solution and 500 ml HAES 10% intravenously per day; maternal heart rate and blood pressure were measured continuously. Prior to and after the therapy the same area of the placenta was examined using CAM; histograms demonstrating the distribution of the intensity values and summation values of the color pixels were calculated.

Results: In 14 patients the fetal outcome was good. The histograms showed in 11/14 cases an increase of low intensity values indicating an improvement of the placental circulation. The summation value of the color pixels as measured by CAM was significantly increased after the therapy in these cases ( p = 0.022). In 10 patients the fetal outcome was unfavorable. The histograms showed a decrease of the intensity values in 6/10 cases. There was no significant change in the summation values of the color pixels after the therapy ( p = 0.139).

Conclusions: CAM sonography demonstrated for the first time a local effect of the HD therapy within the placenta. In the positive case the placental blood circulation will improve and the pregnancy develops favourably (responder). In the negative case there is no change of the placental blood circulation and pregnancy must be terminated due to a pathological fetal heart rate tracing, fetal growth failure or hypertensive disorders (nonresponder).