Renal vascularization indexes and fetal hemodynamics in fetuses with growth restriction.

OBJECTIVE: To identify the correlation between the renal vascularization index (VI), the flow index (FI) and the vascularization and flow index (VFI) and placental and fetal hemodynamics in fetuses with growth restriction. METHOD: Bidimensional ultrasound and three-dimensional power Doppler with the VOCAL technique were used to determine the renal vascular indexes and fetal and placental hemodynamics in fetuses below the 10th percentile for fetal weight. Partial correlation analysis (controlled for renal depth and gestational age) was performed. The fetuses were divided into four groups according to their hemodynamic picture, and renal indexes were compared between the groups. RESULTS: Eighty-one fetuses were evaluated. VI, FI and VFI showed negative correlation with the ductus venosus pulsatility index. VI and VFI showed positive correlations with the amniotic fluid index. The group of fetuses with the worst hemodynamic picture (abnormal umbilical artery, middle cerebral artery and ductus venosus pulsatility indexes) showed significantly lower VI and VFI than the group with no changes in these pulsatility indexes. CONCLUSIONS: Renal vascularization indexes were inversely correlated with ductus venosus pulsatility indexes and were diminished in fetuses showing hemodynamic compromise. These changes might be related to postnatal renal impairment. © 2017 John Wiley & Sons, Ltd.

Elevation of uterine basal tone and fetal heart rate abnormalities after labor analgesia: a randomized controlled trial.

OBJECTIVE: To estimate the effects of combined spinal-epidural and traditional epidural analgesia on uterine basal tone and its association with the occurrence of fetal heart rate (FHR) abnormalities. METHODS: Seventy-seven laboring patients who requested pain relief during labor were randomly assigned to combined spinal-epidural (n=41) or epidural analgesia (n=36). Uterine contractions and FHR were recorded 15 minutes before and after analgesia. Uterine tone was evaluated with intrauterine pressure catheter. Primary outcomes were the elevation of baseline uterine tone and occurrence of FHR prolonged decelerations or bradycardia after analgesia. The influence of other variables such as oxytocin use, hypotension, and speed of pain relief were estimated using a logistic regression model. RESULTS: The incidence of all outcomes was significantly greater in the combined spinal-epidural group compared with epidural: uterine hypertonus (17 compared with 6; P=.018), FHR abnormalities (13 compared with 2; P<.01), and both events simultaneously (11 compared with 1; P<.01). Logistic regression analysis showed the type of analgesia as the only independent predictor of uterine hypertonus (odds ratio 3.526, 95% confidence interval 1.21-10.36; P=.022). For the occurrence of FHR abnormalities, elevation of uterine tone was the independent predictor (odds ratio 18.624, 95% confidence interval 4.46-77.72; P<.001). Regression analysis also found a correlation between decrease on pain scores immediately after analgesia and the estimated probability of occurrence of hypertonus and FHR abnormalities. CONCLUSION: Combined spinal-epidural analgesia is associated with a significantly greater incidence of FHR abnormalities related to uterine hypertonus compared with epidural analgesia. The faster the pain relief after analgesia, the higher the probability of uterine hypertonus and FHR changes. CLINICAL TRIAL REGISTRATION: Umin Clinical Trials Registry, http://www.umin.ac.jp/ctr/index.htm, UMIN000001186 LEVEL OF EVIDENCE: I.

Fetal hemodynamic changes following maternal betamethasone administration in pregnancies with fetal growth restriction and absent end-diastolic flow in the umbilical artery.

OBJECTIVES: To examine the effects of betamethasone administration on umbilical artery (UA), middle cerebral artery (MCA) and ductus venosus (DV) Doppler flow. DESIGN: Longitudinal prospective study. SETTING: Fetal Surveillance Unit, Department of Obstetrics and Gynecology, University of São Paulo, São Paulo, Brazil. POPULATION: Thirty-two singleton pregnancies complicated by fetal growth restriction with absent end-diastolic flow in the UA. METHODS: Pulsatility index (PI) of the UA, MCA and DV was measured from 26 to 34 weeks prior to and within 24 or 48 hours after starting betamethasone treatment course. Analysis of variance for repeated measures was used to determine the changes in the fetal hemodynamic Doppler flow following maternal corticosteroid administration. MAIN OUTCOME MEASURES: Improvement of UA-PI within 24 hours and DV-PIV (venous pulsatility) within 48 hours from the first betamethasone dose. RESULTS: Mean gestational age at delivery was 29.3 (+/-1.8) weeks and birthweight was 806.6 (+/-228.2) g. A reduction in the UA-PI was observed in 29 (90.6%) cases, with return of end-diastolic flow in 22 (68.7%). The mean UA-PI were 2.84 (+/-0.52) before corticosteroid administration, 2.07 (+/-0.56) within 24 hours and 2.42 (+/-0.75) after 48 hours, with a significant difference along the evaluations (p<0.001). No significant changes in the MCA Doppler were observed. DV-PIV decreased from 1.06 (+/-0.23) prior corticosteroids administration to 0.73 (+/-0.16) within 24 hours and 0.70 (+/-0.19) after 48 hours (p<0.001). CONCLUSIONS: There was reduction in the umbilical artery and in the DV pulsatility indices within 24 hours from betamethasone administration that was maintained up to 48 hours.

Fetal gastroschisis: antepartum fetal heart rate analysis by computerized cardiotocography.

OBJECTIVES: To describe the antenatal fetal heart rate (FHR) parameters analyzed by computerizedcardiotocography (cCTG) in fetuses with gastroschisis and compare the FHR parameters with ultrasound gastrointestinal markers. METHODS: A retrospective analysis of antepartum cCTG records were conducted in 87 pregnant cases with fetal gastroschisis between 28and 36 weeks (plus 6 days). A comparative analysis of the median distribution of the following FHR parameters was performed: basal FHR, short-term variation (STV), FHR accelerations and decelerations, episodes of high and low variations, and variations in low and high episodes. FHR parameters and ultrasound gastrointestinal markers were also compared. RESULTS: The majority of FHR parameters did not present significant changes throughout gestation. An increased number of records with episodes of low variation (p = 0.019) and an increased number of accelerations >15 bpm (p = 0.001) were the only observed changes throughout gestation. Stomach herniation was significantly associated with a lower STV (p = 0.018) and a higher frequency of records with low episodes (p = 0.049). CONCLUSIONS: The cCTG analysis indicated that the FHR parameters in fetuses with gastroschisis presented different patterns from those observed in normal fetuses. Stomach herniation was associated with altered FHR patterns.

Predicting pH at birth in absent or reversed end-diastolic velocity in the umbilical arteries.

OBJECTIVE: To investigate arterial and venous blood flow in fetuses with absent or reversed end-diastolic flow in the umbilical arteries and to correlate the Doppler results with umbilical artery blood pH at birth to predict the probability of acidosis at birth. METHODS: Ninety-one fetuses from singleton pregnancies without fetal malformations with a diagnosis of absent or reversed end-diastolic flow in the umbilical arteries were prospectively studied. On the day of delivery, Doppler velocimetry of the umbilical arteries, middle cerebral artery, and ductus venosus was performed and the results were correlated with umbilical artery pH at birth at the following cutoff levels: pH < 7.20, < 7.15, < 7.10, and < 7.05. The association between fetal arterial and venous Doppler velocimetry and acidosis was then individually analyzed by the chi(2) and Fisher exact tests. The ability of these tests to predict the probability of acidosis at birth was estimated using a logistic regression model. RESULTS: There was a negative correlation between pH at birth and umbilical artery pulsatility index (r = -0.39; P < .001) and pulsatility index for veins in the ductus venosus (r = -0.63; P < .001). Assessment of the fetal arterial circulation (middle cerebral artery) showed no statistical correlation with pH at birth. Using logistic regression analysis, probability curves were constructed for pH values less than 7.20 (odds ratio [OR] 8.03), less than 7.15 (OR 11.92), less than 7.10 (OR 12.16), and less than 7.05 (OR 8.20). CONCLUSION: The pulsatility index for veins of the ductus venosus was related to pH at birth, demonstrating that the higher the ductus venosus pulsatility index for veins, the lower the pH at birth. Once the pulsatility index for veins in the ductus venosus is known, the probability of acidosis at birth can be estimated.

Reduced placental volume and flow in severe growth restricted fetuses.

OBJECTIVES: To evaluate placental volume and vascular indices in pregnancies with severe fetal growth restriction and determine their correlations to normal reference ranges and Doppler velocimetry results of uterine and umbilical arteries. METHODS: Twenty-seven fetuses with estimated weights below the 3rd percentile for gestational age were evaluated. Placental volume and vascular indices, including vascularization, flow, and vascularization flow indices, were measured by three-dimensional ultrasound using a rotational technique and compared to a previously described nomogram. The observed-to-expected placental volume ratio for gestational age and observed-to-expected placental volume ratio for fetal weight were calculated. Placental parameters correlated with the Doppler velocimetry results of uterine and umbilical arteries. RESULTS: The mean uterine artery pulsatility index was negatively correlated with the observed-to-expected placental volume ratio for gestational age, vascularization index and vascularization flow index. The observed-to-expected placental volume ratio for gestational age and observed-to-expected placental volume ratio for fetal weight and vascularization index were significantly lower in the group with a bilateral protodiastolic notch. No placental parameter correlated with the umbilical artery pulsatility index. CONCLUSIONS: Pregnancies complicated by severe fetal growth restriction are associated with reduced placental volume and vascularization. These findings are related to changes in uterine artery Doppler velocimetry. Future studies on managing severe fetal growth restriction should focus on combined results of placental three-dimensional ultrasound and Doppler studies of uterine arteries.

[Cardiotocography in pregnancies with absent or reversed end-diastolic velocity in the umbilical arteries: analisys of perinatal outcome]. / Cardiotocografia em gestações com diástole zero ou reversa nas artérias umbilicais: análise dos resultados perinatais.

OBJECTIVES: To study the correlation between cardiotocography parameters and perinatal outcome in pregnancies with absent or reversed end-diastolic velocity (AERDV) in the umbilical arteries. METHODS: One hundred and twenty-seven cases presenting with AREDV followed between 1993 and 2000 were selected for analysis. The last cardiotocographic tracing performed on the day of delivery was reviewed and the following parameters were considered: magnitude of long-term variability, presence or absence of acceleration, late deceleration, variable deceleration, prolonged deceleration, pseudo sinusoidal pattern and the classification in normal, suspected and abnormal tracing. RESULTS: A significant (p<0.05) association was found between abnormal tracing and acidemia at birth (pH inferior to 7.20) with 71.9%, first minute Apgar score inferior to seven (73.4%), newborn intubation at delivery (64.1%), and early neonatal death (20.3%). The absence of acceleration was associated (p<0.05) to acidemia at birth (58.8%), first minute Apgar score inferior to seven (67.7%), newborn intubation at delivery (51%) and neonatal death (29.4%). Low FHR variability (<5bpm) was associated to (p<0.05): acidemia at birth (88.5%), newborn intubation at delivery (69.2%), early neonatal death (34.6%) and neonatal death (42.3%). Late decelerations were significantly (p<0,05) related to acidemia at birth.(78.2%). The severe variable deceleration was associated to (p<0.05): acidemia at birth (79.3%), newborn intubation at delivery (69%) and early neonatal death (17.2%). Prolonged deceleration was associated to (p<0.05) newborn intubation at delivery (70.6%). Pseudo sinusoidal pattern was associated to (p<0.05) early neonatal death (60%). CONCLUSION: The AREDV represents a severe fetal compromise with high risk to neonatal morbidity and mortality, and correlation between cardiotocography abnormalities and adverse perinatal outcome was demonstrated.

Transient accelerations of fetal heart rate analyzed by computerized cardiotocography in the third trimester of pregnancy.

OBJECTIVE: The aim of this study was to investigate the patterns of transient FHR accelerations (10 bpm and 15 bpm) in the third trimester of pregnancy, comparing the occurrence of this event before and after the 32nd gestational week. METHODS: This is a prospective study comparing the results of the computerized cardiotocography of 46 low-risk women with singleton pregnancies, maternal age between 18 and 40 years, gestational age between 28 and 40 weeks, absence of maternal morbidity and adequate fetal growth according to ultrasound. Computed Cardiotocography (8002 Sonicaid System and Fetal Care System) was performed for 30 minutes to analyze the variables of FHR. RESULTS: Twenty-three pregnant women underwent cardiotocography before 32 weeks (mean = 29.9 weeks, SD = 1.4 weeks) and were compared with 23 pregnant women who were examined after 32 weeks (mean = 36.3 weeks, SD = 2.5 weeks). Regarding the characteristics of FHR, fetuses evaluated between 32 1/7 weeks and 40 weeks showed a significantly greater number of accelerations above 15 bpm (median = 5, variation 0-18) than the group of pregnant women from 28 to 32 weeks (median = 4, variation 0 to 10; P = 0.048). There was a significant positive correlation between the number of accelerations above 15 bpm and the gestational age at examination (rho = 0.33; P = 0.026). CONCLUSION: Computerized cardiotocography showed an association regarding the number of transient accelerations greater than 15 bpm in the assessment of both periods before and after 32 weeks of gestational age, suggesting the influence of the maturation of the fetal autonomic nervous system with pregnancy progression.

Intrauterine growth restriction in monochorionic-diamniotic twins.

OBJECTIVE: to evaluate neonatal morbidity and mortality in monochorionic-diamniotic (MCDA) twin pregnancies complicated by selective intrauterine growth restriction (sIUGR) and non-selective intrauterine growth resctriction (nsIUGR). METHODS: neonatal morbidity parameters and mortality were analyzed in 34 twins with IUGR (< 10th percentile on twins' growth charts): 18 with sIUGR and 16 with nsIUGR. The sIUGR group was made up of 18 pregnancies in which growth was restricted in only one fetus (n = 18). The nsIUGR group was composed of 8 pregnancies in which both fetuses presented restricted growth (n = 16). Cases of twin-to-twin transfusion syndrome and fetal malformation were not included in the study. RESULTS: the MCDA twin pregnancies with sIUGR had a higher rate of orotracheal intubation (p = 0.001) and mechanical ventilation (p = 0.0006), as well as longer than average fasting time (p = 0.014) compared to those in which the fetuses had nsIUGR. A higher incidence was also observed of types II and III umbilical artery Doppler velocimetry patterns in the sIUGR cases (p = 0.002). There was no significant difference between the two groups as to mortality during pregnancy and the neonatal period (p = 0.09). CONCLUSION: in MCDA twin pregnancies, sIUGR presents more severe umbilical artery Doppler velocimetry abnormalities and worse morbidity than nsIUGR.

Cord blood B-type natriuretic peptide levels in placental insufficiency: correlation with fetal Doppler and pH at birth.

OBJECTIVE: To examine the correlation of cardiac B-type natriuretic peptide (BNP) concentrations in umbilical cord blood at birth with fetal Doppler parameters and pH at birth. STUDY DESIGN: Prospective cross-sectional study with the following inclusion criteria: women with a singleton pregnancy, placental insufficiency characterized by increased pulsatility index (PI) of the umbilical artery (UA), intact membranes, and absence of fetal abnormalities. The exclusion criteria kept out cases of newborns with postnatal diagnosis of abnormality and cases in which the blood analysis was not performed. The Doppler parameters used were the UA PI, middle cerebral artery (MCA) PI, cerebroplacental ratio (CPR), and ductus venosus (DV) PI for veins (PIV), all converted into zeta scores. Blood samples were obtained from the umbilical cord immediately after delivery to measure the pH of the UA and the BNP. RESULTS: Thirty-two pregnancies with placental insufficiency were included, 21 (65%) with positive diastolic flow and 11 (35%) with absent or reversed end diastolic flow in the UA. The concentration of BNP correlated significantly with the UA PI z-score (rho=0.43, P=0.016), the CPR z-score (rho=-0.35, P=0.048), the DV PIV z-score (rho=0.61, P<0.001), pH at birth (rho=-0.39, P=0.031), and gestational age (rho=-0.51, P=0.003). In the multiple regression analysis, antenatal parameters were included; the DV PIV z-score (P=0.008) was found to be an independent parameter correlating with BNP at birth. Correlation between BNP and the DV PIV z-score was borne out by the regression equation Log[BNP]=2.34+0.13*DV (F=18.8, P<0.001). Correlation between BNP and pH at birth was confirmed by the regression equation Log[BNP]=21.36-2.62*pH (F=7.69, P=0.01). CONCLUSION: The results suggest that fetal cardiac dysfunction identified by BNP concentrations at birth correlated independently with changes in DV PIV and correlated negatively with pH values at birth.

Predicting pH at birth in pregnancies with abnormal pulsatility index and positive end-diastolic velocity in the umbilical artery.

OBJECTIVES: To identify potential associations between fetal surveillance tests and acidosis at birth in pregnancies with abnormal but positive end-diastolic velocity in the umbilical artery. METHODS: A prospective case-control study [group 1: pH < 7.2; group 2: pH ≥ 7.2] including 46 fetuses with abnormal but positive end-diastolic velocity in the umbilical artery was conducted between February 2007 and March 2009. Outcome variables were evaluated by univariate analysis and compared between the two groups. Clinically relevant and statistically significant variables were analyzed by logistic regression. RESULTS: Abnormal nonstress test, presence of deceleration, and absent fetal breathing movements were statistically significant. Logistic regression analysis revealed that fetal heart rate (FHR) deceleration in the nonstress test is the only predictor of fetal acidosis at birth (p = 0.024; OR = 8.2; 95%CI: 1.2-52). CONCLUSIONS: In fetuses with positive end-diastolic flow velocity, acute variables of the antenatal surveillance tests are correlated with acidosis at birth and FHR deceleration in the nonstress test is the only predictor of fetal acidosis.

Fetal venous Doppler in pregnancies with placental dysfunction and correlation with pH at birth.

OBJECTIVES: To determine the correlation between ph at birth and venous Doppler parameters in pregnancies with placental dysfunction. METHODS: This was a prospective cohort study of 58 pregnancies with the diagnosis of placental dysfunction between 26 and 34 weeks of gestation. Inclusion criteria were singleton pregnancies, abnormal umbilical artery (UA) Doppler, fetal growth restriction diagnosed by estimated fetal weight <10th centile for gestational age, intact membranes, and absence of fetal congenital abnormalities. The Doppler measurements were the following: UA pulsatility index (PI), ductus venosus (DV) pulsatility index for veins (PIV), intra-abdominal umbilical vein (UV) time-averaged maximum velocity (TAMxV) and blood flow and left portal vein (LPV) time-averaged maximum velocity (TAMxV) and blood flow. All Doppler parameters were transformed into z-scores (SD values from the mean) according to normative references. RESULTS: The UA pH at birth showed a negative significant correlation with the DV-PIV (p = 0.004) and the DV-PIV z-score (p = 0.004), while LPV TAMxV (p = 0.004), LPV TAMxV z-score (p = 0.002), LPV blood flow (p = 0.01), LPV blood flow normalized (p = 0.04) and UV blood flow (p = 0.04) positively correlated with pH at birth. Multiple regression analysis was performed and the DV-PIV z-score was the variable that independently correlated with pH at birth (p = 0.002). CONCLUSIONS: the present results suggest that changes in fetal venous blood flow, mainly DV and LPV are useful in the management of cases with early onset placental insufficiency and that venous Doppler parameters correlate with pH at birth.

[Assessment of fetal well-being in pregnancies complicated by maternal moderate to severe thrombocytopenia]. / Avaliação da vitalidade fetal em gestações complicadas pela plaquetopenia materna moderada ou grave.

PURPOSE: To analyze the results of assessment of fetal well-being in pregnancies complicated by moderate or severe maternal thrombocytopenia. METHODS: Data from April 2001 to July 2011 of 96 women with a diagnosis of thrombocytopenia in pregnancy were retrospectively analyzed. We analyzed the following tests performed during the antepartum period for fetal assessment: cardiotocography, fetal biophysical profile, amniotic fluid index and umbilical artery Doppler velocimetry. RESULTS: A total of 96 pregnancies with the following diagnoses were analyzed: gestational thrombocytopenia (n=37, 38.5%) hypersplenism (n=32, 33.3%), immune thrombocytopenic purpura (ITP, n=14, 14.6%), secondary immune thrombocytopenia (n=6, 6.3%), bone marrow aplasia (n=3, 3.1%), and others (n=4, 4.1%). Cardiotocography showed normal results in 94% of cases, a fetal biophysical profile with an index of 8 or 10 in 96.9% and an amniotic fluid index >5.0 cm in 89.6%. Doppler umbilical artery velocimetry showed normal results in 96.9% of cases. In the analysis of the major groups of thrombocytopenia, the diagnosis of oligohydramnios was found to be significantly more frequent in the group with ITP (28.6%) compared to the other groups (gestational thrombocytopenia: 5.4% and hypersplenism: 9.4%, p=0.04). CONCLUSIONS: This study indicates that in pregnancies complicated by moderate or severe maternal thrombocytopenia, even though the fetal well-being remains preserved in most cases, fetal surveillance is important in pregnant women with ITP, with emphasis on amniotic fluid volume evaluation due to its association with oligohydramnios.

Reduced placental volume and flow in severe growth restricted fetuses

OBJECTIVES: To evaluate placental volume and vascular indices in pregnancies with severe fetal growth restriction and determine their correlations to normal reference ranges and Doppler velocimetry results of uterine and umbilical arteries. METHODS: Twenty-seven fetuses with estimated weights below the 3rd percentile for gestational age were evaluated. Placental volume and vascular indices, including vascularization, flow, and vascularization flow indices, were measured by three-dimensional ultrasound using a rotational technique and compared to a previously described nomogram. The observed-to-expected placental volume ratio for gestational age and observed-to-expected placental volume ratio for fetal weight were calculated. Placental parameters correlated with the Doppler velocimetry results of uterine and umbilical arteries. RESULTS: The mean uterine artery pulsatility index was negatively correlated with the observed-to-expected placental volume ratio for gestational age, vascularization index and vascularization flow index. The observed-to-expected placental volume ratio for gestational age and observed-to-expected placental volume ratio for fetal weight and vascularization index were significantly lower in the group with a bilateral protodiastolic notch. No placental parameter correlated with the umbilical artery pulsatility index. CONCLUSIONS: Pregnancies complicated by severe fetal growth restriction are associated with reduced placental volume and vascularization. These findings are related to changes in uterine artery Doppler velocimetry. Future studies on managing severe fetal growth restriction should focus on combined results of placental three-dimensional ultrasound and Doppler studies of uterine arteries.