Farhan Hanif

Middle cerebral artery peak systolic velocity: a new Doppler parameter in the assessment of growth-restricted fetuses.

The aims of this study were to determine if there is a relationship between middle cerebral artery (MCA) peak systolic velocity (PSV) and perinatal mortality in preterm intrauterine growth‐restricted (IUGR) fetuses, to compare the performance of MCA pulsatility index (PI), MCA‐PSV and umbilical artery (UA) absent/reversed end‐diastolic velocity (ARED) in predicting perinatal mortality, to determine the longitudinal changes that occur in MCA‐PI and MCA‐PSV in these fetuses, and to test the hypothesis that MCA‐PSV can provide additional information on the prognosis of hypoxemic IUGR fetuses.

Intrauterine growth restriction: How to manage and when to deliver

Intrauterine growth restriction secondary to placental insufficiency is a major cause of perinatal morbidity and mortality in the United States. Once intrauterine growth restriction is identified, obstetrical management is focused on assuring safety while the fetus continues to mature within a potentially hostile intrauterine environment. In the United States, the approach to management and delivery of the premature growth-restricted fetus is often based on serial biophysical profile evaluations, whereas in Europe it is usually based on the results of cardiotocography. However, there is no single test that seems superior to the other available tests for timing the delivery of the growth-restricted fetus. Therefore, the decision to deliver a fetus, especially at <32 weeks, remains mostly on the basis of empirical management.

Fetal Doppler: Umbilical Artery, Middle Cerebral Artery, and Venous System

One of the most important applications of Doppler ultrasonography in obstetrics is the detection of fetal anemia in pregnancies complicated by either red-cell alloimmunization or by other causes of fetal anemia. Doppler of the umbilical artery also has prognostic value in pregnancies affected by twin-twin transfusion syndrome undergoing in-utero intervention. Another potential major application is the use of Doppler ultrasound in the management of intrauterine-growth-restricted fetuses. At the present time, there is no single test that appears superior to the other available tests for timing the delivery of the growth-restricted fetus. Therefore, the decision to deliver a fetus, especially at <32 weeks, remains mostly based on empirical management. Doppler may provide a more reliable and systematic basis for timing these deliveries. This review emphasizes the three following concepts: (a) normal and abnormal Doppler of the umbilical artery, middle cerebral artery, mitral and tricuspid valves, umbilical vein, and ductus venosus; (b) some clinical applications of Doppler sonography in obstetrics; and (c) potential future research of Doppler in obstetrics.

Gestational Age at Delivery and Doppler Waveforms in Very Preterm Intrauterine Growth-Restricted Fetuses as Predictors of Perinatal Mortality

The aim of this study was to compare gestational age at delivery and the performance of middle cerebral artery (MCA), ductus venosus (DV), and umbilical artery Doppler parameters in the prediction of perinatal mortality and morbidity in intrauterine growth‐restricted (IUGR) fetuses delivered at 32 weeks or earlier.

Sequence of cardiovascular changes in IUGR in pregnancies with and without preeclampsia

The aim of this study was to determine the cardiovascular changes sequence in intrauterine‐growth‐restricted (IUGR) fetuses using Doppler ultrasound.

Staging of Intrauterine Growth-Restricted Fetuses

The purpose of this study was to evaluate the value of cardiovascular, ultrasonographic, and clinical parameters for developing a staging classification of intrauterine growth‐restricted (IUGR) fetuses delivered at 32 weeks or earlier.

The Transitional Phase of Ductus Venosus Reversed Flow in Severely Premature IUGR Fetuses

The guiding hypothesis for this work is that in severe intrauterine growth-restricted (IUGR) fetuses, the time from ductus venosus (DV) reversed flow (RF) appearance to intrauterine fetal demise (IUFD) or nonreassuring fetal testing is variable. As such, there must be a transitional phase between the presence of end-diastolic forward flow (FF) and absent or reversed end-diastolic flow (A/REDF). Ductus venosus Doppler was serially studied in 19 IUGR fetuses (estimated fetal weight < 10th percentile and umbilical artery pulsatility index > 95th percentile) from diagnosis until demise or delivery occurring for nonreassuring fetal testing. Ductus venosus waveforms were assessed qualitatively: forward flow versus absent or reversed flow in diastole. Two sets of at least 30 consecutive ductus venosus waveforms were obtained at each examination. If the waveforms differed between the two sets, they were defined as alternating. Cord arterial pH and base excess (BE) were obtained at birth. In 14 cases, DVRF occurred intermittently between periods of FF during the same clinical visit. Intermittent DVRF was present from 2 to 57 days (median, 13 days) and became continuous from 1 to 23 days (median, 7 days) before the occurrence of delivery for nonreassuring fetal testing or fetal demise. One fetus had an abnormal arterial pH (< 7.0) and one had an abnormal BE (< -12). These data show that (1) there is a transitional phase in which DV alternates FF and A/RF before RF becomes persistent; (2) the time from the appearance of DVRF to delivery or IUFD is variable, and (3) not all very preterm IUGR fetuses with continuous DVRF are acidemic. Because of these findings, the decision of delivery regarding early severe IUGR fetuses should be individualized, and the DVRF Doppler information has to be integrated with other antenatal fetal parameters.

OC109: Sequence of cardiovascular changes occurring in severe IUGR fetuses—part II

Objective: To characterize the velocity profiles of the uterine and hypogastric vessels before and after ovarian stimulation in the setting of in-vitro fertilization (IVF), using MSDA and GASP software. Methods: The MSDA system consisted of commercial ultrasound machine (Aloka SSD1400), a personal computer and a proprietary electronic board. Interogated vessels consisted of the uterine and hypogastric arteries and veins in a total of 21 women (15 IVF recipients and 6 egg donors) during ovarian stimulation at different time points. Velocity profiles, relative wall distension rate [WDR (%)] and shear rate [WSR (1/s)] were calculated over multiple consecutives cardiac cycles. The designation of arterial laminar flow was applied if one peak occurred in systole, while if > 1 peak in systole was classified as turbulent. Statistical analysis consisted of Spearman correlation. Results: All vessels displayed a laminar flow pattern, except in 4 cases (2 egg donors and 2 IVF patients), where the arterial flow was turbulent. Interestingly, there were qualitative differences in the velocity profiles in circumstances where conventional Doppler waveforms were identical. Hypogastric artery WDR (left, 2.5 ± 0.5; right, 1.9 ± 1) was highly correlated with the ipsilateral uterine WDR (left, 2.6 ± 0.5; right, 1.9 ± 1, rs = 1.00, p < 0.01). The hypogastric artery WSR (left, 455 ± 217; right, 389 ± 212) was highly correlated with the ipsilateral uterine WDR, (rs = 0.883, p < 0.01). Uterine wall shear rate (left, rs = 0.703; right, 0.805, p < 0.01) but not wall distension rate, was highly correlated to the cycle day. Conclusion: Real time velocity profiles are now possible using MSDA and GASP software. We found substantial differences between our new technology and conventional Doppler. These parameters are being evaluated in ongoing studies to determine their relationship to endometrial receptivity, ovarian function and success or failure of IVF attempts.

OC252: Sequence of cardiovascular changes occurring in severe IUGR fetuses in pregnancies complicated by pre‐eclampsia and in pregnancies without this complication

Objectives: To examine the relationship between smallness, assessed by customized standards, and the predictive value of a normal umbilical artery Doppler. Methods: A cohort was created of 7645 singleton pregnancies without congenital anomalies. Fetuses suspected antenatally of being small for gestational age were referred for assessment by umbilical artery Doppler. The associations with adverse outcome were assessed for small-for-gestational age babies who had normal and abnormal Doppler, compared with neonates who were not small for gestational age. Perinatal outcome indicators were collected, including fetal distress requiring Cesarean section and neonatal morbidity (neonatal intensive care > 14 days, neonatal seizures, intraventricular hemorrhage Grade III or more, periventricular leucomalacia, hypoxic–ischemic encephalopathy, or necrotizing enterocolitis). Results: Of the 369 small-for-gestational age fetuses which had been identified antenatally, 70 (19%) had an abnormal umbilical artery Doppler and the babies from these pregnancies had an elevated risk of fetal distress requiring Cesarean section (OR 5.89; CI, 2.64–11.84) and neonatal morbidity (OR 3.99; CI, 1.04–11.03). However the 299 fetuses (81%) with normal umbilical artery Doppler also had elevated risk of fetal distress (OR 4.49; CI, 2.96–6.66) and neonatal morbidity (OR 2.26; CI, 1.04–4.39). Because of the higher prevalence, many more instances of adverse outcome were attributable to this group than to the group with abnormal Dopper (fetal distress – population attributable risk (PAR): normal Doppler 8.6 vs. abnormal Doppler 2.7; neonatal morbidity – PAR: normal Doppler 4.0 vs. abnormal Doppler 2.2. Conclusions: Smallness for gestational age according to customized weight standards defines a group of pregnancies with significantly elevated risk of adverse perinatal outcome. Normal antenatal umbilical artery Doppler cannot be taken as an indicator of low risk in these pregnancies.

OC116: Ductus venosus SIA Index and a‐wave reversed flow in severely premature growth‐restricted fetuses

test. Results: There were 8 fetal demises (FD), 9 neonatal demises (ND), and 32 neonates survived (NS) at the time of hospital discharge. An ROC curve for the SIA Index in all cases showed less than −1.25 correlated with FD and greater than −1.25 correlated with live birth with 100% sensitivity and 100% specificity. A second ROC curve of live births showed less than 2.07 correlated with NS and greater than 2.07 correlated with ND with a sensitivity of 67% and a specificity of 94%. DV A/REDF correlated with FD and ND with sensitivities of 88% and 78%, respectively, and with NS 32%. Of the 32 NS, 11 (34%) possessed A/REDF at some time, with a median of 11 days before delivery. Conclusions: The SIA Index is a novel Doppler parameter in the assessment of severely premature IUGR fetuses that allows a much more accurate prediction of fetal outcome compared to A/REDF alone. Assessment of the SIA Index should therefore be considered part of the evaluation of IUGR fetuses.