F. H. C. Carvalho

Prediction of acidemia at birth by Doppler assessment of fetal cerebral transverse sinus in pregnancies with placental insufficiency.

To evaluate the prediction of acidemia at birth using cerebral transverse sinus (CTS) Doppler velocimetry and to determine the best parameter and cut‐off values for its prediction in pregnancies complicated with placental insufficiency.

Valores dos parâmetros da dopplerfluxometria do ducto venoso entre a 10ª e a 14ª semana de gestações normais

PURPOSE: to analyze the values of Doppler ultrasound for blood flow velocity in the ductus venosus between the 10th and the 14th week of gestation, during the different phases of the cardiac cycle: ventricular systole (wave S), ventricular diastole (wave D), atrial systole (wave a), and angle-independent indexes. METHODS: Doppler was used in this prospective cross-sectional study to examine 276 single pregnancies. Fetus malformations, abnormal nuchal translucency, and women with clinical pathologies were excluded. A Toshiba SSH-140 ultrasound equipment was used. The derivation of Doppler frequency spectra was carried out according to standardized measurement procedures: less than 30oinsonation angle and 50-70 Hz high-pass filter. The ductus venosus was identified in a median sagittal and ventral plane with the presence of color aliasing due to increase in blood flow velocity. The sample volume (1-2 mm3) was placed immediately at the origin of the ductus venosus. At least three clearly and subsequent waves were available for measurement of standard values. The Levene test and the Bonferroni method were used for statistical analysis. RESULTS: increase in blood flow velocity from 29 cm/s to 37 cm/s (p=0.013) was observed during ventricular systole between the 10th and the 14th week of gestation. Similarly, increase in blood flow velocity was recorded during the ventricular diastole (from 25 cm/s to 32 cm/s, p=0.026). There were no changes in wave a, pulsatility index, and S/a ratio in this period. CONCLUSION: the reference ranges established by this study may serve as the basis for Doppler ultrasound follow-up in a normal patient population. Further studies are required to determine the validity of these parameters and, in particular, for the fetus at risk.

Correlação da área do cordão umbilical com parâmetros antropométricos em gestações normais

OBJECTIVE: To develop a nomogram for the umbilical cord cross-sectional area (UCCSA) in normal pregnancies in women between 20 to 40 weeks gestation. MATERIALS AND METHODS: A cross-sectional study was developed to determine reference ranges for the UCCSA during normal pregnancies (patients with known dates of last menstrual period, and a normal ultrasound examination before the 20th week of gestation). The measurements of the UCCSA were obtained using a plane adjacent to the insertion of the cord in the abdomen. A 3.5 MHz transabdominal transducer was used on all ultrasound equipment utilized (a Synergy Multi Sync M500, a Toshiba 140 and a Toshiba Corevision). The statistical analysis was performed using the SPSS (Statistical Package for Social Sciences) software. RESULTS: The Kolmogorov-Smirnov test showed a normal distribution of the data and the nomogram was constructed by linear regression. The analysis of variance (F test = 356.27) showed that our model was significant at a p < 0.01 level, and therefore represented adequately the studied population. The confidence interval (95%) contained the real value of the UCCSA. The equation constructed for the UCCSA (y) according to the gestational age (x) was: y = -532.27 + 44.358x - 0,655x². CONCLUSION: The nomogram developed for the UCCSA shows a progressive increase of the UCCSA up to the 32nd week, stabilization until the 34th week, and decrease after the 35th week of gestation.

P07.18: Transverse cerebral sinus Doppler velocimetry in the prediction of birth acidemia

an increase of 190.8% (p < 0.05). Vmean of the renal artery increased significantly between the 20–24 week and the 37th–40th week (9.56 cm/s vs. 20.15 cm/s, p < 0.05). Area of the renal artery increased significantly between the 20–24 weeks and the 37–40 weeks (6.78 mm2 vs. 10.12 mm2, p < 0.05). No significant increase in RI or PI was observed. At the 20–24 weeks of gestation, renal artery waveforms consisted of 43.5% type I (only systolic waves) and 56.5% (systolic waves and some diastolic waves). Type III (systolic waves and persistent diastolic waves) was not recognized. At 25–28 weeks, they consisted 28.3% type I, 63.0% type II, and 8.7% type III. At the 29–32 weeks, type I decreased, and frequency of type II was 78.2%. At the 37–40 weeks, 76.1% type III, type II decreased to 23.9%, and type I was not recognized. Conclusions: Vmax was found to be the most effective index because it was easy to measure and the significant change of gestation progresses. The renal blood flow waveforms changed as advanced gestation in normal growth fetuses.

P07.17: Transverse cerebral sinus Doppler velocimetry in the prediction of fetal acidemia: which is the best parameter?

an increase of 190.8% (p < 0.05). Vmean of the renal artery increased significantly between the 20–24 week and the 37th–40th week (9.56 cm/s vs. 20.15 cm/s, p < 0.05). Area of the renal artery increased significantly between the 20–24 weeks and the 37–40 weeks (6.78 mm2 vs. 10.12 mm2, p < 0.05). No significant increase in RI or PI was observed. At the 20–24 weeks of gestation, renal artery waveforms consisted of 43.5% type I (only systolic waves) and 56.5% (systolic waves and some diastolic waves). Type III (systolic waves and persistent diastolic waves) was not recognized. At 25–28 weeks, they consisted 28.3% type I, 63.0% type II, and 8.7% type III. At the 29–32 weeks, type I decreased, and frequency of type II was 78.2%. At the 37–40 weeks, 76.1% type III, type II decreased to 23.9%, and type I was not recognized. Conclusions: Vmax was found to be the most effective index because it was easy to measure and the significant change of gestation progresses. The renal blood flow waveforms changed as advanced gestation in normal growth fetuses.

OC26.04: Screening for chromosomal abnormalities by ductus venosus Doppler in the first trimester

Over the last 10 years 655 fetuses with enlarged nuchal translucency (NT) were referred to our Prenatal Diagnosis department. The follow-up is known in 97% of cases. In 35% of cases a chromosomal anomaly was diagnosed by fetal karyotyping. The overall chance of an adverse outcome for the whole group was 55%. In case of normal chromosomes two standards ultrasound investigations were planned, the firts, shortly after karyotyping was known (13–16 weeks) and the second at 20–24 weeks. Of the remaining 428 fetuses a normal outcome was recorded in 81% of cases. Adverse outcome was subdivided into: spontaneous abortion or intra-uterine death (4%), structural anomalies (7%), genetic syndromes (5%) and termination of pregnancy on parents request (3%). Of the structural anomalies the most frequent were cardiac defects (54%). The chance of an adverse outcome increased progressively with the degree of NT enlargement, whereas the chance of a healthy baby followed the opposite trend. After a normal structural ultrasound investigation the overall chance of a normal outcome was 96%. Interestingly, the chance of a normal outcome after normal ultrasound findings was not anymore influenced by the initial degree of enlargement.

Predição de acidemia fetal mediante dopplervelocimetria do ducto venoso em gestações com insuficiência placentária

Universidade Federal de Sao Paulo (UNIFESP), Escola Paulista de Medicina (EPM) Departamento de Obstetricia

P236: The cylindrical shape of ductus venosus in the first trimester of gestation

Objective: To investigate the geometric shape of the ductus venosus between 10–13 weeks of gestation. Patients and methods: Ductus venosus measurements were performed in 64 normal human fetus using ultrasound color Doppler imaging. The geometrical measurements obtained were: length (n = 64), isthmic width (n = 34) and outlet width (n = 20). For statistical analysis, the analysis of variance, linear regression, Kruskal-Wallis terst and the Spearman correlation were used. Results: At 10–13 weeks of gestation, the ductus venosus length indicates a continuous growth and the width did not change. The measurements (median) were: length = 2 mm, isthimic inlet = 1.4 mm, and outlet width +1.4 mm. Conclusion: The new geometric shape of the ductus venosus between 10–13 weeks of gestation has a cylindrical and not a slender trumpet-like shape as defined previously in the literature.

P237: Reference values of Dopplerfluxometry of the ductus venosus at 10–14 weeks of gestation

Objective: To investigate the geometric shape of the ductus venosus between 10–13 weeks of gestation. Patients and methods: Ductus venosus measurements were performed in 64 normal human fetus using ultrasound color Doppler imaging. The geometrical measurements obtained were: length (n = 64), isthmic width (n = 34) and outlet width (n = 20). For statistical analysis, the analysis of variance, linear regression, Kruskal-Wallis terst and the Spearman correlation were used. Results: At 10–13 weeks of gestation, the ductus venosus length indicates a continuous growth and the width did not change. The measurements (median) were: length = 2 mm, isthimic inlet = 1.4 mm, and outlet width + 1.4 mm. Conclusion: The new geometric shape of the ductus venosus between 10–13 weeks of gestation has a cylindrical and not a slender trumpet-like shape as defined previously in the literature.

Correlation between the umbilical cord cross‐sectional area and fetal anthropometric parameters

A prospective cross‐sectional study was developed to determine the correlation between the umbilical cord cross‐sectional (UCCSA) and fetal anthropometric parameters during normal pregnancies (patients with known dates of LMP and an ultrasound examination before the 20th week, without any pathologic condition). The measurements of the umbilical cord cross‐sectional area were obtained in a plane adjacent to the insertion of the cord in the abdomen, as proposed by Raio et al., 1999, and compared to the biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur length (FL) by the non‐parametric correlation of Spearman. The inclusion criteria were: (1) singleton pregnancy; (2) gestational week >20 weeks; (3) intact membranes; (4) normal umbilical Doppler flow velocimetry. The exclusion criteria, in the presence of any of those were: (1) congenital and/or chromosomal abnormalities; (2) pregnancy complications (any type); (3) inadequate size for gestational agent the time the ultrasound examination was performed, i.e. the weight below the 10th or above the 90th percentile; (4) abnormal AFI. The patients were examined and included only once. The statistical analysis was performed by the program called Statistical Package for Social Sciences (SPSS) and we used a Toshiba 140 with a transabdominal transducer of 3.5 MHz. Our results showed a strong correlation (Spearman rank = 0.610, significant at the level of P < 0.01) between the UCCSA and the estimated fetal weight by ultrasound examination and also with the fetal anthropometric parameters (UCCSA × BPD = 0.622; UCCSA × HC = 0.617; UCCSA × AC = 0.625; UCCSA × FL = 0.604, all of them significant at the level of P < 0.01). We concluded that the UCCSA is a parameter that can be included at the routine of obstetrical ultrasound examinations.