Search

To develop one fetal cardiac volume normality curve and evaluate its behavior during a normal gestation, using a tri-dimensional ultrasound technique. Mainly the fetal cardiac diseases have as an initial presentation an alteration to its volume. These changes are analyzed normally using numerical relations between thoracic perimeter and cardiac perimeter. The 3D technique allows determining its real volume and producing true concepts about one elevated cardiac volume. It was studied 30 patients with gestation age starting at 20 week in a longitudinal evaluation. All patients had an evaluation in first trimester to determine its real gestation age. It was obtained tri-dimensional thoracic blocs for a posterior study using the softwares 3D view for multiplanar purpose and VOCAL for volume purpose. It was possible obtain a normality curve for cardiac volume. It presented as an ascendant curve represented by a polynomial formula of sixth grade with a very low variation. The curve presented an ascendant growing with a linear acceleration. Its acceleration showed to be decreased after the 36th week. Even though we could represent it using a linear formula, it was most according using a polynomial formula of sixth grade. [ABSTRACT FROM AUTHOR]

An abstract of the article "Fetal umbilical and middle cerebral arteries during the 2nd and 3rd trimester in low risk pregnancies: intra- and inter-observer reliability and agreement," by J. C. Lima, A. H. Miyague, F. Mauad Filho, and W. P. Martins is presented.

The authors review the main concepts regarding the importance of cleaning/disinfection of ultrasonography probes, aiming a better comprehension by practitioners and thus enabling strategies to establish a safe practice without compromising the quality of the examination and the operator productivity. In the context of biosafety, it is imperative to assume that contact with blood or body fluids represents a potential source of infection. Thus, in order to implement cleaning/disinfection practice, it is necessary to understand the principles of infection control, to consider the cost/benefit ratio of the measures to be implemented, and most importantly, to comprehend that such measures will not only benefit the health professional and the patient, but the society as a whole.

Our aim was to determine whether rotating the fetus over its largest axis and reducing the rotational step angle can improve reliability/agreement of fetal volume measurements obtained with three-dimensional ultrasonography (3-DUS). Two observers acquired three 3-DUS data sets for a fetus with a crown-rump length between 45 and 84 mm. These observers determined the fetal volume using virtual organ computer-aided analysis (VOCAL), by three different methods, with a rotational step angle of 30°: (1) minimal manipulation of the 3-DUS data set, fetus rotated over any axis; (2) manipulation of the 3-DUS data set until the fetus could be seen in a standardized manner, fetus rotated over its anteroposterior axis; (3) same 3-DUS data set manipulation, fetus rotated over its longitudinal axis. Intra- and inter-observer reliability/agreement was determined with intra-class correlation coefficients and limits of agreement. In addition, we tested the method that provided the best reliability/agreement results using 15° and 9° of rotational step angles. The time taken to manipulate 3-DUS and determine fetal volume was recorded. The best intra- and inter-observer reliability/agreement results were observed when the fetus was rotated over its longitudinal axis. Reducing rotational step angle to 15° or 9° did not further improve reliability/agreement. The observer took approximately 1 min to determine fetal volume using this method. Our findings indicate that fetal volume should be determined by rotating the fetus over its longitudinal axis, at a rotational step angle of 30°, which is relatively fast and allows analysis of fetal volume with good reliability and agreement., (Copyright © 2013 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.)

Purpose: The objective of this study was to describe multiple Doppler ultrasound parameters of ductus venosus and inferior vena cava in fetuses at gestational ages ranging from 22 to 38 weeks., Study Design: In this prospective observational study, Doppler ultrasound exams were performed in 45 healthy fetuses at 22, 26, 34, and 38 weeks. Maximum venous velocity, minimum venous velocity, venous pulsatility index, and venous acceleration time (VAT) (defined as the time between minimum and maximum venous velocity) were evaluated at those gestational periods., Results: Increase in the velocities and decrease in the pulsatility index were observed in these vessels throughout gestational age. The VAT increased with gestational age., Conclusions: The VAT, a Doppler parameter still not described elsewhere, increased during pregnancy could be related to a longer period of time needed to fill the atrium in bigger hearts. In this study, we provide reference values for VAT in healthy fetuses.

Objective(s): We intend to verify if fetal volume and crown-rump length were different between singletons and twins in pregnancies aged from 7 to 10 weeks and to evaluate if fetal volume is more accurate to determine the gestational age than crown-rump length at this gestational age., Study Design: From 52 days (7 weeks and 3 days) to 73 days (10 weeks and 3 days) weekly three-dimensional ultrasonography was performed in 20 twin fetuses and 20 singletons. Crown-rump length and fetal volume using VOCAL were assessed in all examinations. The 'true' gestational age was based on oocyte retrieval., Results: At the age of 52 days, the crown-rump length was 11.74+/-0.27 mm (mean+/-S.D.) and 11.48+/-0.22 mm (singletons and twins, respectively), while the fetal volume was 0.354+/-0.015 cm(3) and 0.324+/-0.012 cm(3). At the gestational age of 73 days, the crown-rump length was 36.19+/-0.90 mm and 35.87+/-0.54 mm and the fetal volume was 6.204+/-0.090 cm(3) and 6.083+/-0.081 cm(3). The total relative increase observed was much higher for fetal volume than for CRL: 1705+/-301% vs. 210+/-33% in singletons and 1827+/-305% vs. 214+/-25% in twins. The 95% limits of agreement (+/-2.3 days vs.+/-3.2 days, fetal volume vs. crown-rump length) and the intraclass correlation coefficients (0.989 vs. 0.978) between the "true" gestational age and that predicted by fetal volume were better than those predicted by crown-rump length. No significant difference was identified between singletons and twins for both fetal volume and crown-rump length., Conclusion(s): Twins and singletons had similar fetal volume and crown-rump length between the 7th and 10th week of gestational age. Additionally, fetal volume assessed by VOCAL was better than crown-rump length to estimate the gestational age at the evaluated period. However, the improvement was small and probably without clinical significance., Condensation: Fetal volume and crown-rump length were similar between singletons and twins. Fetal volume relative increase was higher and the predicted gestational age was better.

Purpose: to describe values found for the resistance index (RI), pulsatility index (PI) and the systole/diastole (S/D) ratio of fetal renal arteries in non-complicated gestations between the 22nd and the 38th week, and to evaluate whether those values vary along that period., Methods: observational study, where 45 fetuses from non-complicated gestations have been evaluated in the 22nd, 26th, 30th and 38th weeks of gestational age. Doppler ultrasonography has been performed by the same observer, using a device with 4 to 7 MHz transducer. For the acquisition of the renal arteries velocity record, a 1 mm to 2 mm probe has been placed in the mean third of the renal artery for the evaluation through pulsed Doppler ultrasonography. The measurement of RI, PI and S/D ratio from three consecutive waves was performed with the automatic mode. To detect significant differences in the indexes' values along gestation, we have compared values obtained at the different gestational ages, through repeated measures ANOVA, followed by Tukey's post-hoc test., Results: There were no significant differences between the right and left renal arteries, when the RI, IP and S/D ratio were compared. Nevertheless, a change in the values of these parameters has been observed between the 22nd week (RI=0.9 +/- 0.02; PI=2.4 +/- 0.02; S/D ratio=11.6 +/- 2.2; mean +/- standard deviation of the combined mean values of the right and left renal artery) and the 38th week (RI=0.8 +/- 0.03; PI=2.1 +/- 0.2; S/D ratio=8.7 +/- 2.3) of gestation., Conclusions: the parameters evaluated (RI, PI and S/D ratio) have presented decreasing values between the 22nd and 38th, with no difference between the fetus's right and left sides.

Endometrial volume and thickness were measured in 20 women undergoing in vitro fertilization on the day before the embryo transfer and one week later by three-dimensional ultrasound. The endometrial volume increase was higher in the 8 pregnant women (0.70 cm(3) at least) than in the 12 nonpregnant women (0.21 cm(3) at most).

Purpose: to compare the intra and interobserver reproducibility of the total thickness measurement of the inferior uterine segment (IUS), through the abdominal route, and of the muscle layer measurement, through the vaginal route, using bi and tridimensional ultrasonography., Methods: the IUS thickness measurement of 30 women, between the 36th and 39th weeks of gestation with previous caesarean section, done by two observers, was studied. Abdominal ultrasonography with the patient in both supine and lithotomy position was performed. In the sagittal section, the IUS was identified and four bidimensional images and two tridimensional blocks of the total thickness were collected through the abdominal route, and the same for the muscle layer, through the vaginal route. Tridimensional acquisitions were manipulated in the multiplanar mode. The time was measured with a chronometer. Reproducibility was evaluated by the computation of the absolute difference between measurements, the ratio of differences smaller than 1 mm, the intraclass coefficient (ICC), and the Bland and Altman's concordance limits., Results: the average bidimensional measurement of IUS thickness was 7.4 mm through the abdominal and 2.7 mm through the vaginal route, and the tridimensional measurement was 6.9 mm through the abdominal and 5.1 mm through the vaginal route. Intra- and interobserver reproducibility of vaginal versus abdominal route: smaller absolute difference (0.2-0.4 mm versus 0.8-1.5 mm), greater ratio of differences (85.8-97.8% versus 48.7-72,8%), with p<0,0001, higher ICC (0.8-0.9 versus 0.6-0.8) and lower concordance limits (-0.9 to 1.5 versus -3.8 to 4 mm) for the vaginal route. Tri versus bidimensional ultrasonography: lower absolute difference (0.2-1.4 versus 0.4-1.5 mm), higher ratio of differences (57.7-97.8% versus 48.7-91.7%) with p>0.05[A1] and similar lower concordance limits (-38 to 3.4 versus -3.6 to 4 mm) for tridimensional ultrasonography and ICC (0.6-0.9 versus 0.7-0.9)., Conclusions: from the above, we came to the conclusion that the measurement of the IUS muscle layer, through the vaginal route using tridimensional ultrasonography is more reproducible. Nevertheless, our results do not indicate that this measurement shows any clinical evidence to predict uterine tear, as that was not the aim of this study. The only work that has correlated the UIS thickness with risk of uterine tear, without interfering in the obstetrician behavior or anticipating delivery, was done by bidimensional abdominal measurements of the total thickness.

Objective: To assess peak systolic velocity values in middle cerebral artery (PSMCA) of normal fetuses from 22nd to 38th week of gestation., Material and Methods: We made a prospective study of 33 healthy fetuses from 22nd to 38th to determine peak systolic velocity by Doppler velocimetry. Doppler ultrasound was performed by a single observer, always using the same apparatus. The Doppler tracing was obtained with a sample volume of 1 mm; placement was on the anterior middle cerebral artery, as close as possible to the skullcap. The insonation angle was kept below 20 degrees and the wall filter was adjusted to a frequency of 50-100 Hz. The PSMCA increases from 26.3 cm/s to 57.7 cm/s in middle cerebral artery from 22nd to 38th week of gestation (p < 0.05). There was a significant positive correlation between PSMCA and the gestational values (p < 0.001, r2 = 60.5%)., Conclusion: In normal fetuses, the PSMCA increases from 22nd to 38th week of gestation. The Doppler velocimetry values for normal fetuses could be compared with those obtained during fetal anemia.

The objective of our study was to assess fetal hemodynamics by Doppler velocimetry during the second half of pregnancy. We carried out a longitudinal study on 33 normal fetuses between the 22nd and 38th weeks of gestation. Doppler velocimetry was performed in the aorta, suprarenal (SRA) and infrarenal (IRA) segments, middle cerebral artery (MCA) and umbilical artery (UA), on the basis of fetal peak systolic velocity (SV), end-diastolic velocity (DV) and resistance index (RI). We used a sample volume of 1 mm, a wall filter of 50 to 100 Hz, a 5 degrees to 19 degrees insonation angle in the MCA and UA, and below 60 degrees in the SRA and IRA. Between the 22nd and 38th weeks of gestation, SV and DV increased in all fetal arteries (p<0.05), but SV decreased in the UA from 52.5 to 46.2 cm/s between the 34th and 38th gestational weeks (p<0.05). The RI was unchanged in the SRA and throughout most of the gestational weeks in the IRA (p>0.05), but decreased from 0.69 to 0.56 in the UA (p<0.05). In the MCA, it decreased from 0.85 to 0.75 between the 26th and 38th gestational weeks (p<0.05). In conclusion, the volume of blood flow in the fetal organs necessary for their development is related to increased SV and DV and to decreased RI. The Doppler velocimetry measurements for normal fetuses could be compared with those for fetuses in high-risk pregnancies.

We made a longitudinal ultrasonographic study of 33 healthy fetuses from 22 to 38 weeks of gestation to determine the acceleration time in the middle cerebral artery (ATMCA) and its relationship with fetal cardiac output. Doppler ultrasound (US) was performed by a single observer always using the same apparatus. The Doppler tracing was obtained with a sample volume of 1 mm; placement was on the anterior middle cerebral artery, as close as possible to the skullcap. The insonation angle was kept between 5 degrees and 19 degrees and the wall filter was adjusted to a frequency of 50 to 100 Hz. The ATMCA was 40 ms at 22 and 26 weeks, 50 ms at 30 and 34 weeks and 60 ms at the 38th week. There was a significant positive correlation between gestational age and ATMCA values (r=0.45, p<0.001). The ATMCA values became significantly higher than the initial values at the 30th week of gestation (p<0.05). The ATMCA values for normal fetuses could be compared with those obtained during high-risk pregnancies; this would be useful for the detection of fetal cardiac anomalies.

Maternal and fetal plasmas from patients with specific hypertensive disease of pregnancy (SHDP) are shown to have a greater vasoconstrictive effect on perfused human unbilical artery than plasma from normal parturients. The vasomotility of isolated segments of artery was determined by measuring perfusion pressure at constant flow rate. The differences were demonstrable with plasmas and artery segments from the same parturients and also when plasma from patients with SHDP and arteries from normal parturients were used. These results, which show that plasmas from SHDP patients have a larger vasoconstrictive effect on human umbilical artery than normal plasma, support and extend the suggestion that there may be humoral mechanism which participates in the physiopathology of SHDP. This humoral factor can be detected with human umbilical artery from both normal and SHDP parturients.

In the present work ketamine was used as anesthetic during the labor in order to evaluate the effect of this anesthetic on the binominal fetus-mother. Two groups of parturients and their fetuses, were studied: 1) The experimental group, with 22 parturients and their fetuses submitted to ketamine anesthesia during the labord, and 2) The control group, with 20 parturients and their fetuses without any analgesic treatment during the labor. In 20 cases of the experimental group the anesthetic was injected during the delivery labor and the other two just before it. It were evaluated in the mother's blood the biochemical parameters of the acid-base balance and others collateral effects of the anesthesia; on the fetus's side the same parameters also and the cardiac frequency. The newborn were evaluated by Apgar Score during the first and fifth minutes of life. The incidence of the spontaneous delivery in the experimental group, was 78%; in 22% of these patients the forceps of relief was used. In 22 cases in which Ketamine was applied it were observed, the following events: elevation of the blood pressure (50%), perineum rigidness (18%), dreams and or hallucinations (18%), increase of the cardiac frequency (9%), apneia (4%) and nausea (4%). It was also observed an increase of uterine tonus an abolishment of abdominal press during the delivery labor, studied through the uterine electromyography register. It was noted after the Ketamine application a fall in the pH of the maternal peripherical venous blood, fetal skull blood and the pH of the blood of the umbilical vein. 22% of the newborns, from the experimental group, presented a depression in the first minute of life (Apgar less than or equals to 6). The pCO2 values in the blood of the umbilical artery were higher in the experimental group than in the control one.

The effect of digitoxin on isolated segments of lateral branches of the human saphenous vein perfused in vitro with constant volumes is reported. Digitoxin, depending on concentraion, effected rise in perfusion pressure and intensification of reaction to norepinephrine. Some venous segments showed spontaneous activity. The tests were supported by histological studies.

The effect of hypertonic glucose infusion on the maternal and fetal acid-base equilibrium was studied in 20 clinically normal parturients and their concepts. Samples of maternal peripheral venous blood and fetal capillary blood were collected before and after intravenous infusion of 25 g of glucose into the mother at 15-minute intervals. No significant alterations in the parameters of the maternal acid-base equilibrium were observed. On the fetal ide, a significant decrease in pO2 at intervals of 30, 45 and 60 minutes after glucose infusion (fig. 1), and an increase of total CO2 after 60 minutes (fig. 2) were observed. These findings did not permit us to state that glucose infusion may be responsible for the alterations found, since it is known that as labor progresses, PO2 tends to decrease while total CO2 tends to increase. On the other hand, an increase in glycemic levels is known to stimulate the rate of glucose consumption at the expense of its aerobic metabolism, by reducing the oxygen level and increasing CO2, the final products of this glucolytic pathway.