High perinatal mortality has been reported in association with the finding of absent end-diastolic flow velocities in the umbilical artery. The fetus is known to centralize its circulation during hypoxemia and abnormal venous blood flow velocities have been reported in cases of heart failure and imminent asphyxia. The aim of this study was to evaluate blood flow velocities recorded with Doppler ultrasound in the umbilical vein, inferior vena cava and middle cerebral artery as predictors of survival in 17 fetuses with absent or reversed end-diastolic flow in the umbilical artery.
There were five perinatal deaths, all having abnormal umbilical cord venous pulsations. An increased proportion of diastolic blood flow velocity in the middle cerebral artery as a sign of hypoxia was found in 12 fetuses without a relationship to perinatal mortality. An increased proportion of retrograde blood flow in the inferior vena cava was recorded in only one fetus, which died on the same day of congestive heart failure, suggesting fetal heart sparing in the remaining complicated pregnancies. The results suggest that abnormal end-diastolic umbilical venous pulsation in the cord is a late and ominous sign of a severely compromised fetus, while abnormal blood flow velocimetry in the middle cerebral artery might be an earlier sign of fetal hypoxia, with a better prognosis. Copyright © 1996 International Society of Ultrasound in Obstetrics and Gynecology