The impact of maternal plasma volume expansion and antihypertensive treatment with intravenous dihydralazine on fetal and maternal hemodynamics during pre‐eclampsia: a clinical, echo‐Doppler and viscometric study

Abstract

K E Y W O R D S:antihypertensive treatment; maternal whole blood viscosity; plasma volume expansion; pre-eclampsia; umbilical artery pulsatility index; umbilical venous volume flow; uterine artery resistance index ABSTRACT Objectives

Effect of antihypertensive therapy with α‐methyldopa on uterine artery Doppler in pregnancies with hypertensive disorders

“…Our data confirm the findings of previous studies indicating that, before antihypertensive therapy, uterine artery PI and RI are increased in women with pre‐eclampsia but not in women with gestational hypertension, compared to normotensive controls23, 28–32. The impairment of uteroplacental perfusion found in pre‐eclampsia can explain the less favorable fetal and neonatal outcomes observed in these cases compared with pregnancies complicated by gestational hypertension33–35.…”

Antenatal dexamethasone and renal vascular resistance in preterm infants

“…16 Nevertheless, it has been shown that dihydralazine administration does not result in any change in umbilical venous cross-sectional area, but decreases umbilical artery pulsatility index. 17 No difference in renal volume was found between infants with and without antecedent of antenatal steroids therapy at a single dose. At this point, it has been suggested that fetal glucocorticoids overexposure has a role in the early life programming of adult cardiovascular and metabolic disorders.…”

“…It has been reported that the use of nifedipine therapy decreases maternal blood pressure levels but does not produce significant difference in the RI in either the fetal or uteroplacental vessels 16 . Nevertheless, it has been shown that dihydralazine administration does not result in any change in umbilical venous cross‐sectional area, but decreases umbilical artery pulsatility index 17 …”

Accurate diagnosis of umbilical circulation

“…We reported a transient decrease (after 1.5 h hemodialysis) and spontaneous recovery (after 3 h hemodialysis) of umbilical arterial resistance index [27], and this change was thought to be a result of transient maternal hypovolemia. Boito et al reported that the umbilical arterial resistance index decreased with maternal plasma volume following dihydralazine administration expansion in pre-eclamptic patients [28]. They reported that the maternal blood pressure also simultaneously decreased.…”

“…Antihypertensive agents such as nicardipine [33], niphedipine [34], and methyldopa [35] have reported no significant effects on umbilical arterial flow. However, hydralazine was reported to decrease umbilical arterial pulsatility indices [28,36].…”