Measure of hemodynamic patterns by thoracic electrical bioimpedance in normal pregnancy and in preeclampsia

To compare the differences in the hemodynamics between normal pregnancy and preeclampsia, using thoracic electrical bioimpedance.

We compared heart rate, end-diastolic volume, systolic volume, cardiac output, ejection fraction and peripheral vascular resistances in 18 healthy pregnant women with 15 with preeclamptic women at the following intervals: third trimester, 48 h post-partum, 2 and 6 months post-partum. We took the measurements by thoracic electrical bioimpedance. Statistical analysis was performed by means of Wilcoxon rank-sum test and p < 0.05 was considered statistically significant.

The heart rate was lower in the preeclampsia group during the third trimester and the systolic volume was also lower at 48 h post-partum; this implies a lower cardiac output in women with preeclampsia during pregnancy and in the immediate puerperium. The systemic vascular resistances were higher in preeclampsia in the third trimester and at 48 h post-partum. At 2 and 6 months post-partum, the hemodynamic situation had equalized in both groups.

Preeclampsia is a situation of low cardiac output and high peripheral resistances compared with a normal pregnancy.