Volume 27, Issue 2

Objective: Characteristic changes in ductus venosus (DV) blood velocity and pulsations in the umbilical vein (UV) have been described during imminent fetal asphyxia. The aim of this study was to examine fetal venous blood velocity in relationship to pressure gradient across the DV during hypoxia in a fetal lamb preparation. Methods: In general anesthesia, a cesarean section was performed on seven pregnant ewes, the fetus was exteriorized and put into a heated waterbath with uninterrupted umbilical circulation. Pressure measurements in the UV and inferior vena cava (IVC) were performed with the catheter tips on both sides of the DV. Fetal hypoxemia was induced by giving the ewe 12 % oxygen in inhaling air. Pressure across the DV and Doppler velocimetry were repeatedly measured during hypoxemia. Blood velocity was recorded in the DV and UV by Doppler ultrasound. Results: Before hypoxia the median pressure gradient across the DV was in systole 1 mmHg and 0.31 mmHg in end-diastole and during hypoxemia 1.5 mmHg and zero, respectively. The pressure difference across the DV was constant during hypoxemia irrespective of the presence of umbilical venous pulsations or heart rate. IVC-pressure was greatly influenced by fetal heart rate (FHR). A small but linear fall in systolic IVC pressure was seen with increasing FHR. In end-diastole the IVC pressure changed in a parabolic fashion, with increasing pressure during brady- and tachycardia. Pulsations in the UV also showed a parabolic relationship to FHR and central venous pressure. DV end-systolic and end-diastolic blood velocity changed during hypoxemia in direct relationship to FHR and central venous pressure, but without direct relationship to fetal blood gases. Conclusion: The pressure gradient across the DV is constant during hypoxemia. Changes in central and umbilical venous pressure are directly related to FHR. Umbilical venous and DV blood velocity changed in direct relationship to FHR and central venous pressure.

The aim of our study was to assess the volume of the gestational sac and yolk sac throughout the first trimester of pregnancy, and to establish the relationship between the yolk sac volume measurements and vascularity visualization rates. Eighty women with uncomplicated singleton pregnancies between 5 and 12 weeks were evaluated by three-dimensional and color Doppler ultrasound (Combison 530, Kretztechnik). Regression analysis revealed exponential rise of the gestational sac volume with gestational age throughout the first trimester. An exponential rise of the yolk sac volume was noticed between gestational weeks 5 and 8, followed by gradual increase of the yolk sac volume between the gestational weeks 8 and 10. After reaching the plateau from 10 to 11 weeks, yolk sac volume started to decrease. The highest visualization rates for the yolk sac vessels were obtained between gestational weeks 7 and 8. When yolk sac reached the maximum size between 10 and 11 weeks, reduced vascularity was demonstrated. Three-dimensional ultrasound allowed estimation of the gestational sac and yolk sac volumes throughout the first trimester of pregnancy. Both of these measurements seem to be useful prognostic parameters for the pregnancy outcome. The combination of functional and volumetric data provides much useful information on early human development.

The aim of the study was to correlate intra-observer reproducibility of the nuchal translucency measurements by two-dimensional and three-dimensional transvaginal ultrasound. Examinations were performed on 120 women undergoing ultrasound screening at 10 to 14 weeks' gestation. They were examined by two experienced ultrasonographers using both methods two times consecutively. Statistical analysis for the assessment of intra-observer reproducibility was paired t-test. Nuchal translucency measurements were obtained in 100 % of cases with three-dimensional sonography compared to only 85 % with two-dimensional sonography. Better intra-observer reproducibility was obtained for three-dimensional than for two-dimensional ultrasound. Three-dimensional transvaginal ultrasound improves accuracy of nuchal translucency measurement allowing appropriate mid-sagittal section of the fetus and clear distinction of the nuchal region from the amniotic membrane.

In this study we compared the distribution of blood flow to the liver in growth-retarded fetuses whose estimated weight was < 5 th centile with normal-weight fetuses. As expected, the relative venous blood flow to the liver was reduced, with blood flowing preferentially through the ductus venosus. However, the total blood supply seemed to be maintained by a concomitant, significant increase in arterial blood flow through the hepatic artery. Absolute flow velocities such as the peak, minimum diastolic and temporal average velocities were changed, as was the flow waveform. Effectively, the deficiency in venous supply was made up for by an increase in arterial blood flow. This compensatory effect may be crucial for maintaining liver function in times of low portal venous blood supply. It thus makes sense to regard the liver as the fourth preferential organ for arterial blood supply in the compromised fetus, besides heart, brain, and adrenals.

Although the renal artery blood flow velocity has been investigated recently using the ultrasound Doppler method, little is known about the longitudinal change of renal artery blood flow velocity and its relationship with urine volume in very low birth weight infants. Thus, we measured renal artery blood flow velocities by means of the pulse Doppler method in 28 very low birth weight infants. Maximum, minimum, and mean blood flow velocities were determined at postnatal days 0, 1, 2, 3, 4, 5, 6, 13, 20, and 27. The resistance index was also calculated. The maximum and mean blood flow velocities increased gradually after birth, and were significantly higher at 13, 20, and 27 days after birth. The minimum blood flow velocity and the resistance index were relatively constant during the study period. The mean blood flow velocities were also analyzed for any correlation with urine volume. There was a poor correlation between urine volume (ml/kg/day) and mean blood flow velocity (cm/s) (Y = 2.38X + 57.4, Y: urine volume, X: mean blood flow velocity, n=161, r=0.338, P < 0.01). However, if the mean renal artery blood flow velocity was less than 10 cm/s, oliguria was observed in most cases. The measurement of the renal artery blood flow velocities appears to be useful in understanding the background condition of renal function in very low birth weight infants.

This study was conducted to determine the risk factors of the late hyporegenerative anemia in Rh-isoimmunized infants. Data on 36 infants with rhesus hemolytic disease were analyzed. The mean gestational age and birth weight were 36 ± 1.3 weeks and 2837 ± 403 grams respectively. Twenty-seven infants (75 %) received between 2 and 8 intravascular intrauterine blood transfusions. Fourteen infants (39 %) required simple packed red blood cell transfusions and 11 infants (31 %) required exchange blood transfusion in the immediate postnatal period. Thirty infants (83 %) developed late anemia and required blood transfusions at a mean postnatal age of 43.3 ± 15.7 days. Sixty-four percent of infants who had exchange blood transfusions did not develop late anemia, while 92% of infants who did not require exchange blood transfusion developed late anemia, and the difference was statistically significant (P = 0.035). Serum erythropoietin levels were determined in 8 infants immediately before simple transfusion for late anemia. The media serum erythropoietin level was 21.2 mU/ml, ranging between less than 10 to 114.2 mU/ml. We conclude that late hyporegenerative anemia is common among Rh isoimmunized infants, regardless of the intravascular intrauterine transfusion. Exchange blood transfusion was associated with less occurrence of late anemia.

We evaluated a screening program for the detection of congenital cytomegalovirus in 3075 unselected pregnant women. From each live-born child urine for CMV culture was collected within 7 days after birth. Each fetus expelled after a spontaneous second trimester abortion and each stillborn infant were also evaluated for a possible congenital CMV infection. For each congenital infection stored maternal sera were analysed to determine whether maternal infection was primary or recurrent. Fifteen out of the 3075 pregnancies studied resulted in a congenitally infected infant (0.49 %). Nine maternal CMV infections were primary infections; five were recurrent infections, and in one case the type of infection could not be determined. Three congenital infections resulted in severe sequelae, leading to the termination of pregnancy in two instances and to neonatal death in one case. One of these severe fetal infections was due to a recurrent maternal infection. Follow-up of the other 12 neonates demonstrated hearing disorders in two children. One was born after a primary maternal infection and one after a recurrent maternal infection. We conclude that congenital CMV infections occurs in 0.49% of all pregnancies in the population studied. Twenty percent of the congenitally infected infants present severe sequelae at birth or during pregnancy, and an additional 17% have audiological deficits at 1 year of age. Severe sequelae may occur after both primary and recurrent maternal CMV infection.

Perinatal hemochromatosis is a rare disorder with an enormous iron overload in the parenchymal organs, especially the liver, pancreas, heart and endocrine glands. Elements of the reticuloendothelial system are relatively spared. The clinical course is rapidly progressive and the disease is invariably fatal. Several siblings are described in the literature. Herein, we describe one pair of full siblings affected by the disease, wherein the clinical presentation was hydrops. We suggest that hemochromatosis should be considered in the differential diagnosis of hydrops fetalis.

A 34-year-old Japanese woman (gravida 2, para 2) with polyhydramnios and non-immunological hydrops fetalis was referred to our department at 32 weeks of gestation. On admission, the blood pressure was 120/60 mmHg and there was no pitting edema of the lower extremities. An ultrasound examination disclosed a large placental tumor 5.8 cm × 4.4 cm × 4.8 cm. Fetal lung compression was suspected because the lung-thorax transverse area ratio was 0.13. The preload index of the inferior vena cava was 0.74, suggesting fetal cardiac failure. After fetal pleural effusion was aspirated, lung compression developed. Cordocentesis was performed at 33 weeks of gestation, and the fetal karyotype was confirmed to be 46, XY from an umbilical blood cultivation. The patient underwent a cesarean section at 33 weeks of gestation due to severe uterine contraction after preterm PROM. The baby was a 3,840 g male with a distended abdomen. Apgar score at 1 minute was 1. A chest X-ray demonstrated respiratory distress syndrome. The baby was discharged on the 69th day after birth and he is now 2 years and 9 months old and healthy.

We report on a term infant with a severe fetomaternal hemorrhage that caused a serious anemia that was surmounted after several transfusions. After the initial complications, such as persistent pulmonary circulation, severe anemia and thrombocytopenia, the outcome was good. We discuss the importance of a long-term followup of affected children, as well as their mothers. No clear parameters for a real prognosis are available. A follow-up is needed in order to detect possible complications in neurological development.

The fulminant forms of congenital myotonic dystrophy, which rapidly lead to death, are difficult to diagnose. The case described illustrates the roles of persistent pulmonary hypertension in such a fatal form.