End-diastolic Blood Flow In Umbilical Artery Research Articles

Abnormal Umblical Artery Doppler is Utilized for Fetuses with Intrauterine Growth Restriction Birth at 280/7–336/7 Gestational Weeks

Purpose: To compare short-term perinatal outcomes in preterm infants with intrauterine growth restriction (IUGR) in those with absent or reversed end-diastolic umbilical artery blood flow (AREDF) to those with normal end-diastolic umbilical artery blood flow (NEDF). Methods: This study included preterm births (280/7–336/7 gestational weeks) with IUGR with AREDF (n = 86) or NEDF (n = 27). Results: There were lower mean gestational weeks, birth weights, and a higher ratio of corticosteroid application in the AREDF group (p < 0.05). The mean length of neonatal intensive care unit stay of the AREDF group was significantly longer (p < 0.001). Sepsis and feeding intolerance ratios in the AREDF group were also significantly higher (p = 0.041 and p < 0.001 respectively). Conclusions: Patients with IUGR and umbilical Doppler abnormalities have longer neonatal intensive care unit stays.

The value of middle cerebral artery to umbilical artery ratio by Doppler velocimetry in low risk postdate pregnancies

Background and objective: Placental insufficiency is the primary cause of intrauterine growth restriction in normally formed fetuses and can be identified using middle cerebral artery to umbilical artery ratio Doppler velocimetry, and provide an estimate of downstream placental vascular resistance and placental blood flow. There is a strong association between reduced end-diastolic umbilical artery blood flow velocity and increased vascular resistance in umbilical placental microcirculation. Doppler ultrasound can assess the uteroplacental blood flow just before labor. This study aimed to investigate the use of the fetal cerebroumbilical ratio to predict the intrapartum fetal compromise in appropriately grown fetuses. Methods: A comparative cross-sectional study set at Sulaimania Maternity Teaching Hospital, Sulaimania, Iraq, from January to June 2015. The study recruited 121 cases, fetal biometry and Doppler indices were measured before established labor. The intrapartum and neonatal outcome details recorded. Results: Infants delivered by cesarean section for fetal compromise had significantly lower cerebroumbilical ratio than those born by spontaneous normal (none assisted) vaginal delivery and by cesarean section for other intrapartum causes. Infants with cerebroumbilical ratio 10th percentile. A cerebroumbilical ratio >90th percentile appears protective against cesarean section for fetal compromise. Amniotic fluid index of < 5 was associated with an increased cesarean section for fetal indication. Conclusion The cerebroumbilical ratio can identify fetuses at high risk of intrapartum fetal compromise. As a confounding variable, the amniotic fluid index was a useful tool for surveillance in prolonged pregnancy.

Pathophysiology of placental-derived fetal growthrestriction.

Placental-related fetal growth restriction arises primarily due to deficient remodeling of the uterine spiral arteries supplying the placenta during early pregnancy. The resultant malperfusion induces cell stress within the placental tissues, leading to selective suppression of protein synthesis and reduced cell proliferation. These effects are compounded in more severe cases by increased infarction and fibrin deposition. Consequently, there is a reduction in villous volume and surface area for maternal-fetal exchange. Extensive dysregulation of imprinted and nonimprinted gene expression occurs, affecting placental transport, endocrine, metabolic, and immune functions. Secondary changes involving dedifferentiation of smooth muscle cells surrounding the fetal arteries within placental stem villi correlate with absent or reversed end-diastolic umbilical artery blood flow, and with a reduction in birthweight. Many of the morphological changes, principally the intraplacental vascular lesions, can be imaged using ultrasound or magnetic resonance imaging scanning, enabling their development and progression to be followed invivo. The changes are more severe in cases of growth restriction associated with preeclampsia compared to those with growth restriction alone, consistent with the greater degree of maternal vasculopathy reported in the former and more extensive macroscopic placental damage including infarcts, extensive fibrin deposition and microscopic villous developmental defects, atherosis of the spiral arteries, and noninfectious villitis. The higher level of stress may activate proinflammatory and apoptotic pathways within the syncytiotrophoblast, releasing factors that cause the maternal endothelial cell activation that distinguishes between the 2 conditions. Congenital anomalies of the umbilical cord and placental shape are the only placental-related conditions that are not associated with maldevelopment of the uteroplacental circulation, and their impact on fetal growth is limited.

Fetal growth restriction and cardiovascular outcome in early human infancy: a prospective longitudinal study.

The association between low birth weight and premature cardiovascular disease has led to the "prenatal origin of adult disease-hypothesis". We postulated that fetal growth restriction is associated with cardiovascular changes detectable at birth and in early infancy. Fifty-two appropriately grown fetuses (AGA) and 60 growth-restricted fetuses (FGR) with (n=20) or without (n=40) absent or reversed end-diastolic umbilical artery blood flow were prospectively examined by echocardiography before birth, at 1week and 6months of life. The impact of growth restriction on postnatal blood pressure, heart rate, cardiovascular dimensions, and function, as well as on vascular morphology of umbilical cord vessels was studied. FGR fetuses displayed significant blood flow redistribution and were delivered earlier with lower birth weights than AGA fetuses. After adjustment for gender, gestational age, and weight at birth, there were no intergroup differences in blood pressure, heart rate, left ventricular morphology, mass, and performance, and in cord vessel morphology. During the first 6months of life brachioradial pulse wave velocity increased more in FGR fetuses, while other parameters describing vascular stiffness remained comparable between the groups. Fetal growth restriction had no detectable adverse impact on cardiovascular dimensions and function at birth. Cardiovascular findings also remained comparable during the first 6months of life between the groups except a higher increase in brachioradial pulse wave velocity in the FGR group. Our observations suggest that abnormalities that link reduced intrauterine growth with premature cardiovascular diseases may commence later in childhood, indicating a potential window for screening and prevention.

Case 2: Refractory Hypertension in a Neonate

A 5-day-old female infant born at 351/7 weeks is transferred to our neonatal intensive care unit (NICU) for evaluation and management of systemic hypertension. She is twin A of a monochorionic diamniotic pregnancy complicated by twin-to-twin transfusion syndrome in which she is the donor twin. On fetal ultrasonography performed before delivery, twin B has polyhydramnios and a pericardial effusion, and twin A has reversed end-diastolic umbilical artery blood flow. The twins are born by emergency caesarean delivery due to concern for fetal status. Her Apgar scores are 4 and 8 at 1 and 5 minutes, respectively. Her birth weight is 1,990 g. In the NICU, blood pressures are noted to be elevated with recordings consistently above 120/100 mm Hg by an oscillometric device. Echocardiography reveals left ventricular hypertrophy with mild tricuspid and mitral regurgitation. On arrival at our NICU, her weight is 1,830 g, and blood pressure is 124/97 mm Hg. Four quadrant blood pressures do not identify a gradient between the upper and lower extremities. Physical examination is unrevealing: cardiac auscultation reveals a regular rate and rhythm with no murmurs, symmetric and palpable femoral and brachial pulses, and no abdominal masses or renal artery bruits. Serum electrolytes are remarkable for mild hyponatremia (sodium, 130 mEq/L [130 mmol/L]; potassium, 6.3 mEq/L [6.3 mmol/L]; chloride, 101 mEq/L [101 mmol/L]; bicarbonate, 17 mEq/L [17 mmol/L]; blood urea nitrogen, 10 mg/dL [3.6 mmol/L]; and creatinine, 0.7 mg/dL [53 μmol/L]). Renin level is elevated at 270 ng/mL/h (expected for age, 1.4–7.8 ng/mL/h), and aldosterone level is also …

Pregnancies Complicated by Twin???Twin Transfusion Syndrome: Outcome and Long-term Neurologic Follow Up

From 15% to 35% of monochorionic twin pregnancies reportedly are complicated by twin-twin transfusion syndrome (TTTS). This condition reflects an imbalance of communication between the 2 fetal circulatory systems. Changesin blood volume between the donor and recipient twins, leading to different intravascular pressures, could be responsible. Chronic changes could include polyhydramnios and a volume overload syndrome of tricuspid regurgitation and hypertrophic myocardiopathy in the recipient twin and, in the donor twin, oligohydramnios and growth retardation. With expectant management, up to 90% of donor and recipient twins fail to survive the perinatal period. The authors reviewed 32 cases of sonographically diagnosed TTTS seen before 34 weeks gestation. Standard care was based on amnioreduction performed under local anesthesia. TTTS was diagnosed before 24 weeks gestation in 23 of the 32 cases. Three of 34 live-born infants died before discharge, for an overall perinatal mortality rate of 23%. The median gestational age at delivery was 31 weeks, and birth weights averaged 1200 g. All neonatal deaths followed delivery before 28 weeks gestation; neonatal weight was less than 1000 g in these cases. Among pregnancies followed after 24 weeks, 70% of infants were alive, and in 50% of cases both neonates survived. Neurologic follow up of 31 infants after a mean interval of 2 years showed that 58% of infants were normally developed neurologically. Eight infants had major and 5 minor neurologic disabilities. Three pregnancies were selectively terminated; all these infants lived, and all but one had normal neurologic findings at follow up. Both a lack of end-diastolic umbilical artery blood flow and a birth weight less than 1000 g predicted higher perinatal mortality. TTTS still carries high perinatal mortality and frequent problems in neurologic development. Amnioreduction appears to be effective, presumably by providing optimal blood exchange and lessening imbalance between the 2 circulations.

Doppler velocimetry for predicting fetal death in a twin pregnancy

Doppler velocimetry for predicting fetal death in a twin pregnancy

The utility of umbilical artery Doppler investigation in women with the HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome

Objective: Our aim was to study the utility of umbilical artery Doppler velocimetry in the management of women with the HELLP (hemolysis, elevated liver enzymes, and low platelets) syndrome. Study Design: Fetuses of women with the HELLP syndrome underwent ultrasonographic evaluation at initial presentation. An abnormal umbilical artery Doppler study was defined as a systolic/diastolic ratio >5.0. The systolic/diastolic ratios were correlated with outcome variables including laboratory findings, latency, mode of delivery, and birth weight. Results: Fifty women were enrolled into the study. Eighteen of the fetuses (36%) had abnormal waveforms, with 8 fetuses demonstrating either absent or reversed end-diastolic umbilical artery blood flow. The mean umbilical artery systolic/diastolic ratio was significantly higher for fetuses with intrauterine growth restriction or who were small for gestational age than for those without these diagnoses (P = .001, for each). No correlation was observed between the systolic/diastolic ratio and the laboratory findings at admission, the degree of hypertension at admission, or the latency to delivery (all, P > .05). No woman with a fetus at a viable gestational age having abnormal Doppler waveforms had a successful vaginal delivery. Conclusion: Abnormal umbilical artery Doppler velocimetry is associated with a higher risk of fetal growth restriction and a high likelihood of cesarean delivery. These values were not correlated with the severity of maternal disease. (Am J Obstet Gynecol 2001;184:1087-9.)

REVERSED DIASTOLIC UMBILICAL ARTERY FLOW IN THE FIRST TRIMESTER ASSOCIATED WITH CHROMOSOMAL FETAL ABNORMALITIES OR CARDIAC DEFECTS

In Brief Background Six cases have been reported of reversed end-diastolic umbilical artery (UA) blood flow at 10–14 weeks' gestation. Four were associated with chromosomal anomalies, and one showed congenital heart disease. Cases This report describes two cases of reversed end-diastolic UA flow at 10 and 12 weeks' gestation with increased nuchal translucency in which cytogenetic analysis by chorionic villus sampling showed triploidy (69,XXX) and trisomy 9, respectively. In second case, the fetus had a ventricular septal defect. Conclusion Reversed end-diastolic UA flow in the first trimester might be an important sign of chromosomal abnormalities in early pregnancy and might be a useful signal for the diagnosis of early cardiac defects. Reversed end-diastolic umbilical artery blood flow potentially predicts chromosomal fetal abnormalities or cardiac defects in the first trimester.

Absence of end-diastolic umbilical artery blood flow predicts poor fetal outcome despite normal blood gases

A case is reported in which the fetal acid-base status was assessed by means of cordocentesis in a fetus without end-diastolic umbilical artery blood flow. The absence of end-diastolic flow was not associated with acidosis or hypoxia. However, the fetal condition deteriorated 3 days later, which suggests that even with a normal fetal acid-base status, an extended margin of safety cannot be assumed with the absence of end-diastolic umbilical flow.