Severe IUGR Fetuses Research Articles

The effect of intraumbilical fetal nutrition via a subcutaneously implanted port system on amino acid concentration by severe IUGR human fetuses.

To determine if intrauterine intraumbilical supplementation with amino acids (AA) and glucose can improve neonatal outcome of severe growth restricted human fetuses (IUGR). Prospective pilot study of intrauterine treatment of severe IUGR fetuses [n=14, 27 weeks of gestation (range 23-31)] with cerebroplacental ratio <1, with long-term intraumbilical AA and glucose supplementation (10% of feto-placental blood volume/day) using a perinatal port system alone (n=5) or combined with hyperbaric oxygenation (n=1, HBO) vs. control group (n=8). The duration of continuous intraumbilical AA/glucose supplementation was 11 (6-13) days. Daily intravascular fetal nutrition significantly prolonged the brain sparing to delivery interval by 24 (14-33) days vs. 5.6 (2-12) days in controls. Fetal nutrition reduced blood flow resistance in the placental circulation but did not affect the Doppler profile of cerebral arteries. Higher weight gain of 113.5 (36-539) g was observed following supplementation compared to 33.3 (8-98) g in the control group (P<0.05). In spite of this, fetuses below 28 weeks of gestation did not sufficiently benefit from infused commercial AA. We found a reduced fetal plasma concentration of the essential AA histidine, threonine, lysine and arginine, and non-essential AA taurine, in severe IUGR fetuses in both groups. Long-term supplementation with a commercial AA formula led to a slight, but not significant, reduction of histidine, threonine, lysine, arginine, asparagine and glutamine. However, the concentration of tryptophan and glutamic acid slightly increased. HBO can be combined with AA supplementation via a port system. In one case, the port system was also successfully used for fetal blood transfusion. Intravascular treatment of IUGR with fetal nutrition can prolong pregnancy with severe placental insufficiency and brain sparing for many weeks. However, rather than normalizing AA concentrations, an enhanced AA imbalance was observed in IUGR fetuses following supplementation. These deviations in AA concentrations prevent the recommendation for use of commercial AA solutions for prenatal treatment of extreme preterm IUGR fetuses.

333: Mitral and tricuspid E/A ratio abnormality and timing of delivery of severe IUGR fetuses

333: Mitral and tricuspid E/A ratio abnormality and timing of delivery of severe IUGR fetuses

OP14.12: Independent and combined contribution of cardiovascular Doppler parameters to short‐term prediction of mortality in severe IUGR

Objectives: To evaluate the independent and combined contribution to short-term predictive value for mortality in severe IUGR of clinically used and recently described cardiovascular Doppler parameters. Methods: Umbilical artery, middle cerebral artery, ductus venosus (DV), aortic isthmus flow index and modified-myocardial performance index (Mod-MPI) were measured in a cohort of 97 preterm IUGR fetuses. Logistic regression was performed to select those variables that were independently associated to perinatal mortality, and an algorithm to estimate probabilities of death was constructed including the best combination of parameters. Results: A combination of gestational age (below or above 28 weeks), DV atrial flow (positive or absent-reverse) and ModMPI (normal or above 95th percentile) had the highest predictive value for perinatal mortality in IUGR cases. An algorithm including these 3 parameters had a better predictive accuracy than any single parameter. The risk for death below and above 28 weeks respectively was: normal DV and Mod-MPI, 18% and 0.1%; either abnormal, 70–73% and 6–7%; both abnormal, 97% and 45%. Conclusions: The use of composite cardiovascular Doppler scores may help to refine considerably the short-term prediction of perinatal mortality at different gestational ages in severe IUGR fetuses.

735: Doppler and BPP as predictors of outcome in severe IUGR fetuses

735: Doppler and BPP as predictors of outcome in severe IUGR fetuses

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

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

A longitudinal study of the middle cerebral artery pulsatility index and peak systolic velocity – is there a correlation between their trends and fetal demise?

The longitudinal changes that occur in the middle cerebral artery (MCA) pulsatility index (PI) in severe IUGR fetuses remain unclear. Animal studies have shown that blood velocity is a better indicator of blood flow than angle independent indexes. The aims of this study were to determine 1) the longitudinal changes that occur in the MCA-PI and MCA-PSV in severe IUGR fetuses; and 2) the correlation between these two parameters and fetal demise.

Hemoglobin concentration in IUGR fetuses with ductus venosus reversed flow delivered at < 32 weeks' gestation

REVERSED FLOW DELIVERED AT ! 32 WEEKS’ GESTATION FARHAN HANIF, ERICH COSMI, GIANCARLO MARI, Wayne State University, Obstetrics/ Gynecology, Detroit, Michigan, University of Padua, Padua, Italy, Wayne State University, Obstetrics & Gynecology, Detroit, Michigan OBJECTIVE: Ductus venosus reversed flow is considered one of the last parameters to become abnormal in IUGR fetuses before demise. A fetal response to chronic hypoxia is an increased hemoglobin level. The aim of this study was to determine whether a correlation exists between the hemoglobin and the ductus venosus Doppler in IUGR fetuses. STUDY DESIGN: The study population consisted of 25 patients diagnosed to have IUGR fetuses [EFW ! 3rd percentile, and an umbilical artery pulsatility index (PI) O 95 % confidence interval] in which the last Doppler studies were performed at a median interval of 1 day (range 1 to 8 days) before delivery. The fetuses, based on ductus venosus Doppler, were divided into two groups: (a) presence of forward flow during the atrial systole (a wave), and (b) absent or reversed flow of the diastole. Neonatal hemoglobin was measured on day one of life. The relation between the multiples of the median (MoM) for the hemoglobin concentration and ductus venosus Doppler were evaluated by an independent t-test. P ! 0.05 was considered statistically significant. RESULTS: Among the 25 fetuses who met the inclusion criteria, gestational age at delivery ranged between 24.6 weeks and 32 weeks (median: 27.1 weeks). Hemoglobin values ranged from 1.06 MoM and 1.83 MoM (median: 1.38 MoM) in the group with ductus venosus forward flow (n = 16) and it was between .83 MoM and 1.37 MoM (median: 1.15 MoM) in the 9 fetuses with ductus venosus reversed flow (p ! 0.05). CONCLUSION: These data strongly suggest that in the less severe premature IUGR fetuses the initial response to chronic hypoxia is a compensatory increased hemoglobin value. When the condition becomes more severe, however, this process is deficient, as demonstrated by the low value of hemoglobin in IUGR fetuses with ductus venosus reversed flow.

OP07.16: Regional cerebral blood flow perfusion as measured with fractional moving blood volume at different hemodynamic stages in severe IUGR fetuses

Objective: To study the aortic isthmus (AoI) circulation in preterm growth-restricted fetuses (IUGR). Methods: Fifty one IUGR fetuses with either an umbilical artery (UA) pulsatility index (PI)>95th centile or a cerebroplacental ratio 95th centile was shown in 21/51 cases (41%). No adverse perinatal outcome was significantly associated with neither a high PI or low absolute velocities. Comparing group 1 (anterograde) and group 2 (retrograde) significant differences were found in birth weight (p < 0.01), gestational age at delivery (p < 0.001), UA pH values (p < 0.001) and need of mechanical ventilation (p < 0.01). Perinatal mortality was higher in group 2 than group 1 (5.7% vs 60%; p < 0.001). A significant correlation (p < 0.001) was found between retrograde flow in the AoI and adverse perinatal outcome. Conclusions: The decrease in AoI absolute velocities is likely to reflect a decrease in AoI blood flow. Retrograde blood flow in the AoI is clearly related to adverse perinatal outcome.

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.

P10.26: Temporal sequence of hemodynamic changes in severe IUGR fetuses: a randomised study

P10.26: Temporal sequence of hemodynamic changes in severe IUGR fetuses: a randomised study

OC20.06: Epidemiologic and statistical pitfalls in prediction models for fetal weight estimation

ultrasound units. Thanks to this venous flows in the fetus can be reproducibly measured. Different methodologies are a source of systematic errors, but they do not impair their possible diagnostic usage within centers. Errors due to diameter of the vessel and angle of interrogation of the Doppler beam are in fact limited by the quality of digital imaging. A third source of errors remains the difference between the ideal flow model as perfect parabolic flow and the real flow along any specific fetal vessels. However, while technological researches are ongoing, diagnostic application of volume flow are within reach. Umbilical venous flow can be measured and significant reductions in growth restricted fetuses can be diagnosed and followed. This is the base to understand the redistribution of flow at the liver cross roads. In normal pregnancies the blood shunted by the ductus venosus progressively decreases down to a 20% of the umbilical flow, in severe IUGR fetuses this percentage is dramatically inverted, and mirrored by a parallel ductal a-wave reduction. This inversion can become so sever as to draw blood from the portal sinus into the ductus venosus. Severe liver underperfusion and organ damage is the net result of this changes in flow redistribution. Umbilical and liver venous volume flow qualifies today for a powerful instrument to monitor growth restricted fetuses Similar changes in flow redistribution can be measured at the level of the heart and brain even though arterial flow volume measurements in such small vessels are probably limited by the higher expertise required.

OC20.02: Volume flow estimation

In the last twenty years measurement of fetal volume flow, was perceived as a possible direct insight into the core of pathophysiology, not just how it looks, but how it works. The real limitation was set by expensive research ultrasound machines, and by the expertise of research sonologists, until when high technology digital instruments became the standard of quality commercial ultrasound units. Thanks to this venous flows in the fetus can be reproducibly measured. Different methodologies are a source of systematic errors, but they do not impair their possible diagnostic usage within centers. Errors due to diameter of the vessel and angle of interrogation of the Doppler beam are in fact limited by the quality of digital imaging. A third source of errors remains the difference between the ideal flow model as perfect parabolic flow and the real flow along any specific fetal vessels. However, while technological researches are ongoing, diagnostic application of volume flow are within reach. Umbilical venous flow can be measured and significant reductions in growth restricted fetuses can be diagnosed and followed. This is the base to understand the redistribution of flow at the liver cross roads. In normal pregnancies the blood shunted by the ductus venosus progressively decreases down to a 20% of the umbilical flow, in severe IUGR fetuses this percentage is dramatically inverted, and mirrored by a parallel ductal a-wave reduction. This inversion can become so sever as to draw blood from the portal sinus into the ductus venosus. Severe liver underperfusion and organ damage is the net result of this changes in flow redistribution. Umbilical and liver venous volume flow qualifies today for a powerful instrument to monitor growth restricted fetuses Similar changes in flow redistribution can be measured at the level of the heart and brain even though arterial flow volume measurements in such small vessels are probably limited by the higher expertise required.

P05.03: Longitudinal antenatal testing alterations in severe IUGR fetuses

Objective: To assess the longitudinal changes in Doppler velocimetry, FHR tracing and BPP in compromised IUGR fetuses. Methods: A prospective longitudinal study of 186 IUGR fetuses. All fetuses were enrolled in the study in the moment abdominal circumference was <10 percentile, plotted on the population growth curve. In all fetuses a daily FHR tracing, Doppler velocimetry twice weekly has been performed to assess the umbelical artery (UA), middle cerebral artery (MCA), ductus venosus (DV) and umbilical vein (UV) blood flow. The BPP and Amniotic fluid index was evaluated twice weekly. Results: Of 186 fetuses enrolled in the study 86 did not showed Doppler alteration and were not enrolled in the study. Gestational age at time of admission ranged from 19 to 39 weeks of gestation. 100 IUGR fetuses showed Doppler velocimetry alteration in the moment or after the enrollment. In all fetuses the first antenatal testing to show alteration was increased resistance of the UA (100%); UA AEDF (52%), UA RF (26%); brain sparing effect in the MCA (38%); abnormality in the DV (absent or reversed diastolic flow) and UV pulsations (20%). BPP and FHR tracing was abnormal in 30% of the fetuses and in all of them these changes occurred after Doppler velocimetry alterations with a mean time of 3.8 days. AFI was below the normal ranges in 42% of fetuses. Conclusions: Severe IUGR fetuses show a specific temporal sequence antenatal testing alterations consisting in Doppler velocimetry alterations FHR tracing become abnormal too late, and are the last changes seen in IUGR fetuses as well as the BPP and AFI.

F60Umbilical vein blood flow in growth restricted fetuses

ObjectiveThe present study was designed to determine whether specific umbilical blood flow is reduced in IUGR fetuses.SubjectsThirty‐seven IUGR fetuses of different clinical severity were examined by Doppler ultrasound within four hours of the last nonstress test prior to delivery.MethodAbsolute and weight specific umbilical vein (UV) flow were calculated from measurements of UV diameter and UV mean velocity. UV diameter, velocity and UV flow were calculated also per unit head (HC) or abdominal circumference (AC) and correlated with gestational age.ResultsUV flow per kilogram was significantly lower in the more severe IUGR fetuses (abnormal umbilical arterial p.i.) than in normal comparable fetuses (P &lt; 0.001). UV flow per unit head circumference was significantly lower in the three groups (P &lt; 0.001) than in the control population. The UV diameter/HC was normal whereas UV velocity/HC was significantly lower in IUGR fetuses than in comparable controls.ConclusionsThe present study clearly establishes that umbilical venous blood flow is reduced in IUGR fetuses on a weight specific basis. The sonographic growth parameter which best distinguishes umbilical flow differences of IUGR fetuses from normal fetuses is the head circumference.