Search

An abstract of the conference paper "Sotalol and digoxin in fetal atrial flutter: correlation with fetal cardiac output, ejection fraction by planimetrie and middle cerebral artery" by J. C. Otero and colleagues is presented.

An abstract of the conference paper "Doppler indices of the middle cerebral artery in fetuses with cardiac defects associated with impaired cerebral oxygen delivery in utero. Is there a brain sparing effect?," by C. Berg, and colleagues is presented.

Objective: To evaluate changes in the temporal evolution and regional distribution of arterial brain Doppler parameters in relation to different stages of hemodynamic adaptation in fetuses with severe intrauterine growth restriction (IUGR). Methods: Thirty-six fetuses with severe IUGR ( 2 SD) were evaluated longitudinally with pulsed Doppler ultrasound at four different hemodynamic stages: Stage 1 (n = 36), mean UA-PI > 2 SD or absent UA end-diastolic flow; Stage 2 (n = 34), abnormal middle cerebral artery (MCA) PI (mean < 2 SD); Stage 3 (n = 30), reversed UA end-diastolic flow; Stage 4 (n = 12), absent or reversed atrial flow in the ductus venosus. In addition, 36 normally grown fetuses were studied for comparison. PI and time-averaged maximum velocity (TAMXV) in the MCA and the anterior cerebral (ACA), pericallosal (PER) and posterior cerebral (PCA) arteries were measured. Results: In IUGR fetuses, PI values from all arteries were significantly reduced at Stage 2. At Stages 3 and 4, ACA-PI and PCA-PI did not change further, whereas MCA-PI and PER-PI showed a slight increase. In the ACA, MCA and PER, TAMXV in Stage 2 increased significantly. In Stages 3 and 4, ACA and PER-TAMXV remained unchanged, whereas MCA-TAMXV showed a slight decrease, mirroring the PI values. PCA-TAMXV values were similar to controls at all stages. Conclusion: In IUGR fetuses, the brain arteries differ in the magnitude and time sequence of Doppler parameters in relation to systemic hemodynamic adaptation, suggesting the existence of regional brain redistribution processes. [ABSTRACT FROM AUTHOR]

Objectives To analyze the interobserver reliability of measurement of the middle cerebral artery (MCA) pulsatility index (PI) at two different sampling sites. Methods This study included 100 consecutive singleton pregnancies between 24 and 40 weeks with normal fetal growth. The PI was calculated by two independent operators at proximal and distal sampling Sites of the near-field MCA. Reliability analyses were performed between observers at each sampling site by means of the intraclass correlation coefficient (ICC) for agreement. Differences between observers were explored and agreement limits calculated by means of the Bland-Altman test. Results Satisfactory flow velocity waveforms were obtained successfully in each fetus at both sampling sites. Peak systolic, end-diastolic and time-averaged maximum velocities were significantly higher at the proximal compared with the distal sampling site. Conversely, PI was significantly higher at the distal compared with the proximal site. ICCs for PI were 0.3 and 0.33 at the proximal and the distal sampling sites, respectively. The 95% interval of the PI differences between observers were + 0.91 and — 1.14 at the proximal and + 1.03 and – 1.08 at the distal sampling sites. In about 30% of the cases the PI difference between observers was greater than 0.5 at both sampling sites. Conclusions Moderate interobserver reliability in the measurement of end-diastolic and time-averaged is maximum MCA flow velocities results in limited agreement of the PI calculation at both proximal and distal sampling sites. These results may preclude its clinical applicability. [ABSTRACT FROM AUTHOR]

Objective To assess the role of peak systolic velocity in the middle cerebral artery (MCA-PSV) in the management of pregnancies complicated by Kell isoimmunization. Methods Sixteen fetuses were monitored by conventional protocol (Group 1) and eight fetuses by an MCA-PSV-guided protocol (Group 2). The conventional protocol included a weekly ultrasound evaluation and measurement of maternal anti-Kell titers every 4—6 weeks. In Group 2 Doppler assessment of the MCA-PSV was performed at intervals of 4 to 7 days and MCA-PSV >1.5 multiples of the median (MoM) was considered as an indication for fetal blood sampling (FBS). Results No parameter emerged as a reliable predictor of isoimmunization severity in Group 1. In Group 2, no FBS was necessary in one case since the MCA-PS V values obtained during the follow-up were < 1 .29 MoM. In two cases the first FBS was already indicated after 1 week of follow-up, but five other fetuses were followed for 3–9 weeks before FBS was indicated. All fetuses with MCA-PSV > 1.5 MoM prior to intrauterine transfusion (IUT) had severe fetal anemia on FBS. In fetuses with severe anemia on the first PBS, the MCA-PSV values 7 days before the first FBS were < 1.29 MoM (four cases), between 1.29 and 1.5 MoM (two cases) and > 1.55 MoM (one case). Conclusions In the management of Kell isoimmunization invasive procedures may be avoided by implementing MCA-PSV measurements. Delineation of appropriate intervals between reassessments, the reliability of MCA-PSV following repeated IUTs, and cut-off values for FBS await further study. [ABSTRACT FROM AUTHOR]

Objective To construct normal ranges for umbilical artery pulsatility index (UA PI), middle cerebral artery pulsatility index (MCA PI) and cerebroplacental ratio (CPR) in prolonged pregnancies according to strict methodological criteria using polynomial regression analysis. Methods This was a retrospective, cross-sectional observational study involving 140 women, 10 women for each gestational day between 287 and 300 days of gestation. Fetal Doppler parameters were assessed to construct normal reference ranges for UA PI and MCA PI. CPR was calculated as a ratio of MCA PI/UA PI. Results Mathematical modeling of the data demonstrated that the optimal fit was a linear polynomial one. Mean, 5th and 95th centiles were calculated for UA, MCA and CPR and centile curves from the regression analysis were constructed. Conclusions Reference ranges for UA PI, MCA PI and CPR in prolonged pregnancies have been constructed. MCA PI shows a wider range than previously reported in the literature. [ABSTRACT FROM AUTHOR]

Objective In previous pilot studies, fetal vein of Galen (GV) blood velocity has been shown to be non-pulsatile in normal pregnancies. A pulsating pattern in high-risk pregnancies has been related to adverse outcome of pregnancy. The aim of this study was to establish reference ranges for fetal cerebral venous blood flow and compare them to the recordings in high-risk pregnancies in terms of predicting adverse perinatal outcome. Methods The GV, straight sinus (SS) and transverse sinus (TS) were located by color Doppler ultrasound in 189 normal pregnancies between 23 and 43 weeks of gestation. Recordings were also made in 102 pregnancies complicated by pregnancy-induced hypertension and/or intrauterine growth restriction. The following parameters were measured: peak systolic velocity, minimum diastolic velocity, time-averaged maximum velocity, pulsatility index for veins (PIV) and preload index (PLI). GV pulsations were noted. In high-risk pregnancies, Doppler measurements were correlated to pregnancy outcome, including emergency operative intervention and/or neonatal distress. Umbilical vein and umbilical, uterine and middle cerebral artery blood velocities were also recorded at the same time. Results In normal pregnancy, pulsating venous blood velocity was observed in GV in 8% of cases, in SS in 79% of cases and in TS in 100% of cases. GV and SS maximum velocity increased with gestational age and TS-PIV showed linear decreasing values and TS-PLI showed increasing values with gestational age. In high-risk pregnancies, pulsating blood velocity in the GV was found in 59 (58%) cases and was related to adverse outcome of pregnancy including mortality. Abnormal values for TS-PIV and PLI and SS maximum velocity were found in nine, six and five cases, respectively and were only related to perinatal mortality. GV pulsations were more frequent than umbilical venous pulsations. Conclusions Of the fetal cerebral veins studied, the presence of pulsations in the GV seems to be the best predictor of adverse outcome of high-risk pregnancy. Pulsations in the GV are more frequent than in the umbilical vein and might therefore appear earlier during worsening fetal condition, and thus be of potential value for fetal surveillance in high-risk pregnancies. [ABSTRACT FROM AUTHOR]

Objective To investigate the role of Doppler studies in predicting individual fetal demise in patients scheduled for selective laser photocoagulation of communicating vessels (SLPCV) for twin-twin transfusion syndrome (TTTS). Methods Doppler studies of the umbilical artery, umbilical vein, ductus venosus, tricuspid valve regurgitation and middle cerebral artery were performed in the donor and recipient twins before and 24 hours after SLPCV. Results were analyzed cross-sectionally and longitudinally. As multiple comparisons were made, an a priori alpha rejection was set at P < 0.001. Results One hundred and ten consecutive patients were available for analysis. Overall fetal survival was 68.6% (151/220) with at least one survivor in 88.2% (97/110) of cases. Absent or reversed end-diastolic velocity in the umbilical artery of the donor twin was the only preoperative Doppler result predictive of intrauterine fetal demise (IUFD) (10/15, 66.7%, P < 0.001). Postoperatively, reversed flow during atrial contraction in the ductus venosus of the donor twin showed a trend towards prediction of IUFD of this fetus (4/5, 80%, P = 0.007). No other Doppler studies, including the longitudinal analyses, were predictive of IUFD. Conclusions Our data suggest that preoperative absent or reversed end-diastolic velocity in the umbilical artery may be useful in predicting individual fetal demise of the donor twin in TTTS patients scheduled for SLPCV. This may reflect the role of decreased individual placental mass that may be associated with some donor twins. The inability of other Doppler studies to predict individual IUFD may be explained preoperatively by the effect of the interfetal vascular connections on the individual Doppler signals and postoperatively by the effect of surgery or the timing of the assessment. Our findings may be important in patient counseling, in furthering understanding of the disease, and perhaps in improving surgical technique. [ABSTRACT FROM AUTHOR]