A longitudinal analysis of arterial dopler parameters in growth restricted fetuses

Abstract

Doppler parameters enable noninvasive and direct detection of placental insufficiency and brain sparing effect, which occurs as an adaptive mechanism to chronic hypoxemia. It is of great interest if further changes of Doppler parameters, which occur after the detection of the first pathologic value, can anticipate a moment of fetal distress. We investigated growth-restricted fetuses with the brain sparing effect in the time interval between the detection of blood flow redistribution until the distress. The aim of our study was to evaluate longitudinally Doppler parameters in umbilical (Aum), medial cerebral (MCA), renal (AR) and femoral (AF) artery, and find: 1) if there are significant changes in their value; 2) the character and time interval of these changes; and 3) if they differ from changes in biophysical profile (BFP). Prospective clinical study evaluated 35 pregnancies with fetal growth restriction. Fetuses were selected for the study if: 1) there were pathologic cerebral/umbilical (C/U) ratio, 2) at least four Doppler examinations in 3-4 days interval were performed and 3) prepartal fetal distress, defined as silent fetal heart rate pattern with spontaneous and late decelerations, was present. In 28 neonates after delivery umbilical artery gas and acid-base status was determined. Blood flow velocity waveforms were evaluated in Aum, MCA, AR, and AF. Arterial blood flow was estimated by pulsatility index (Pi), while in Aum we also used: present end-diastolic velocity (PEDV), absent end-diastolic velocity (AEDV) and reverse end-diastolic velocity (REDV). All of the fetuses were monitored by cardiotocogram (CTG) once to twice a day and by BFP twice a week. Elective Cesarean section was done in the presence of distress, except if severe immaturity or extreme malnutrition occurred. Etiological factors of placental insufficiency were: 1) hypertensive syndrome (n = 26), 2) chronic renal disease (n = 3), 3) primary antiphospholipid syndrome (n = 2), 4) diabetes mellitus (n = 1), 5) cardiac disease (n = 1) and 6) unknown (n = 2). Initial Doppler examination, with the detection of pathological C/U, was done in time interval between 26. to 32. weeks of gestation (wg) (29.4 +/- 2.5); delivery was between 29. to 34. wg (32.2 +/- 1.9); and average body weight was 1327 +/- 245 g. Pathological BFP was registered in 91.4% of fetuses. Cesarian section has not been done, in spite of distress, in two fetuses (5.7%) due to their extreme immaturity and/or malnutrition, so they died "in utero". Hypoxemia was registered in 96.4% (27/28) neonates, while acidosis in 71.4% (20/28). Neonatal morbidity was 93.9% (31/33), neonatal mortality 8.6%, while perinatal mortality was 14.3%. We found high significant difference (P < 0.001) in Pi Aum, Pi ACM and Pi AR in the time interval between the detection of pathological C/U ratio and fetal distress, while the difference was insignificant for the values of Pi AF (table). The value changes are characterized by: continuing increase of Pi Aum, with a maximum in the last week before the distre...

Cysteinylation of maternal plasma albumin and its association with intrauterine growth restriction

“…The mechanism for a change in the albumin profile during UPI, towards an abundance of cysteinylated albumin, is suggested by details of the transsulfuration pathway (Miles and Kraus, 2004). Initially, UPI leads to fetoplacental hypoxemia and subsequent acidosis (Mikovic et al, 2003). This ischemic environment is conducive for the formation of homocysteine.…”

Prediction of perinatal outcome in high-risk pregnancy by Doppler ultrasound: a prospective cohort study

“…According to Mikovic and colleagues, for the high-risk group, the average birth weight was 1572 grams, and the rate of maternal death was 14.3%. 17 In the current study, in the high-risk group with abnormal Doppler indices, was discovered a 1974gram average birth weight and a perinatal death rate of 3.33 percent. The diagnostic accuracy of Doppler in our study compared to other studies is depicted in (Table 5).…”

Renal Function and Urine Production in the Compromised Fetus

“…Furthermore, using cordocentesis in the SGA fetuses, a significant, direct correlation was found between blood oxygen deficit and increased renal artery PI . Moreover, in a study of 35 IUGR fetuses, the PI in the fetal renal arteries was significantly increased (Mikovic et al, 2003). In studies of fetal urine production, it was demonstrated that the PI in the renal artery was higher in IUGR than in AGA fetuses and that it displayed a negative correlation with the urine production rate and the amniotic fluid volume (Miura, 1991).…”

“…Several studies demonstrate associations between increased impedance in the fetal renal arteries and factors suggestive of compromised fetal conditions and, in some studies, also reduced urine production rates (Mikovic et al, 2003;Miura, 1991;Stigter et al, 2001;Vyas et al, 1989). In one study, the renal artery flow-velocity wave forms were examined in normal and hypoxemic human fetuses .…”