Fetal venous flow and cerebroplacental index indicators of fetal hypoxia in severe preeclamptic women

Abstract

Background: Doppler ultrasound of the uterine and fetoplacental circulation is an important tool to determine complications associated with fetal growth restriction and fetal distress due to hypoxemia or asphyxia as occurring with hypertensive disorders of pregnancy. Also fetal cardiac anomalies, placental malformations and umbilical cord alterations can be diagnosed. Objectives: To determine the predictive value of cerebroplacental index and Aranzio’s venous duct abnormal flow measured by Doppler ultrasound in patients with preeclampsia, in relation to adverse perinatal outcomes. Design: Prospective, non experimental, longitudinal, correlation study. Setting: Fetal Medicine and Prenatal Diagnosis Unit, High Risk Obstetrical Service, Hospital Nacional Guillermo Almenara Irigoyen, EsSalud, Lima, Peru. Participants: Pregnant women with diagnosis of severe preeclampsia and their fetuses. Interventions: Doppler ultrasound examinations were done to determine cerebro placental ratio and Aranzio’s venous duct abnormal flow within seven days before childbirth in 160 patients with severe preeclampsia. Chi (x ²) square test and Fisher exact test were used for statistical analysis, with 0,05 level of significance, 95% confidence interval. Main outcome measures: Adverse perinatal outcomes. Results: Abnormal both cerebroplacental ratio and Aranzio’s venous duct flow were found in 39,4% (63/160) of  patients. These patients had a high probability of intrauterine growth retardation (IUGR), oligohydramnios and cesarean section (p< 0,05) with high sensitivity for Apgar < 7 at 5 minutes, pH <7,2 in umbilical artery, cesarean section for fetal distress and admission to NICU. Conclusions: Alteration of both ultrasound Doppler cerebroplacental index and Aranzio’s venous duct flow detected up to 65% of newborns with adverse perinatal results due to fetal hypoxia and was a statistically significant predictive test of severe IUGR and oligohydramnios in patients with severe preeclampsia.