Photoacoustic assessment of the fetal brain and placenta as a method of non-invasive antepartum and intrapartum monitoring.

A noninvasive monitor for concurrent evaluation of placental and fetal sagittal sinus sO 2 for both antepartum surveillance at the late 2nd and 3rd trimesters and intrapartum monitoring would be a great advantage over current methods. A PA fetal brain and placental monitor has potential value to rapidly identify the fetus at risk for developing hypoxia and ischemia of a sufficient degree that brain injury or death may develop, which may be prevented by intervention with delivery and other follow-up treatments.

Doppler Ultrasonography of the Fetal Tibial Artery in High-Risk Pregnancy and Its Value in Predicting and Monitoring Fetal Hypoxia in IUGR Fetuses.

Background and Objectives: Intrauterine growth restriction (IUGR) is the term used to describe a fetus whose estimated weight is less than the 10th percentile of its age growth curve. IUGR is the second most common cause of perinatal death. In many cases there is a deficiency in the standardization of optimal management, prenatal follow-up and timing of delivery. Doppler examination is the most sensitive test that can assess the condition of the fetus and indicate fetal intrauterine hypoxia. Numerous studies of the fetal intrauterine state focus on the umbilical artery and the fetal cerebral blood vessels, while the peripheral arteries have so far received insufficient attention. Materials and Methods: We present a case of an IUGR fetus monitored with a non-stress test (NST) and a Doppler examination of the fetal arteries (tibial, umbilical, middle cerebral and uterine) and the ductus venosus. In this case the first early sign of fetal hypoxia was revealed by blood flow changes in the tibial artery. Results: We hypothesize that peripheral vascular changes (in the tibial artery) may more accurately reflect the onset of deterioration in the condition of the IUGR fetus, such that peripheral blood flow monitoring ought to be employed along with other techniques already in use. Conclusion: This paper describes the clinical presentation of an early detection of late IUGR hypoxia and claims that blood flow changes in the tibial artery signal the worsening of the fetus's condition.

Chronic hypoxia in pregnant mice impairs the placental and fetal vascular response to acute hypercapnia in BOLD-MRI hemodynamic response imaging.

INTRODUCTION: Brief hypercapnic challenge causes acute placental hypoperfusion with fetal brain sparing on BOLD-MRI. We hypothesize that this non-invasive imaging strategy can distinguish between normal pregnancy and chronic placental hypoperfusion (using the maternal hypoxia model). METHODS: Eighteen pregnant female ICR mice were randomized to three groups: normoxia, late-onset hypoxia (12%O2;E13.5-17.5) and early-onset hypoxia (12%O2;E10.5-17.5). On E17.5, animals were imaged in a 4.7-T Bruker-Biospec MRI scanner. Fast coronal True-FISP was performed to identify organs of interest (placenta and fetal heart, liver and brain). BOLD-MRI was performed at baseline and during a 4-min hypercapnic challenge (5%CO2). %-change in placental and fetal signal was analyzed from T2*-weighted gradient echo MR images. Following MRI, fetuses and placentas were harvested, weighed and immuno-stained. RESULTS: In normoxic mice, hypercapnia caused reduction in BOLD-MRI signal in placenta (-44% ± 7%; p < 0.0001), fetal liver (-32% ± 7%; p < 0.0001) and fetal heart (-54% ± 12%; p < 0.002), with relative fetal brain sparing (-12% ± 5%; p < 0.0001). These changes were markedly attenuated in both hypoxia groups. Baseline fetal brain/placenta SI ratio was highest in normoxic mice (1.14 ± 0.017) and reduced with increasing duration of hypoxia (late-onset hypoxia: 1.00 ± 0.026; early-onset hypoxia: 0.91 ± 0.016; p = 0.02). Both hypoxic groups exhibited fetal growth restriction with prominent placental glycogen-containing cells, particularly in early-onset hypoxia. There was increased fetal neuro- and intestinal-apoptosis in early-onset hypoxia only. CONCLUSIONS: BOLD-MRI with brief hypercapnic challenge distinguished between normoxia and both hypoxia groups, while fetal neuroapoptosis was only observed after early-onset hypoxia. This suggests that BOLD-MRI with hypercapnic challenge can identify chronic fetal asphyxia before the onset of irreversible brain injury.

Cardiac Doppler in poorly controlled gestational diabetics and its link to markers of intra-uterine hypoxia and adverse outcome.

The aim of the study was to investigate foetal cardiac function using the modified myocardial performance index (Mod-MPI) in poorly controlled gestational diabetics and its link with intrauterine markers for hypoxia and to an adverse outcome. In a prospective, cross sectional study, 44 consecutive women with severe or poorly controlled gestational diabetic pregnancies in their third trimester on insulin therapy were recruited and matched with 44 women with normal pregnancies which served as the control group. Using Doppler echocardiography the foetal Mod-MPI was calculated. The foetal Mod-MPI was significantly higher in the diabetic group compared to the controls indicating significant myocardial dysfunction. The Mod-MPI served as an excellent marker of adverse outcomes. Foetal myocardial function was significantly impaired in poorly controlled gestational diabetics and there was a significant link of Mod-MPI to intrauterine markers of hypoxia, as well as to an adverse outcome. Mod-MPI has the potential to improve foetal surveillance in gestational diabetes.IMPACT STATEMENTWhat is already known on this subject? Abnormal foetal cardiac function, as reflected in the modified myocardial performance index, has been reported to be significantly increased in foetuses of poorly controlled diabetics managed on insulin.What do the results of this study add? There is a significant link between abnormal foetal cardiac function to intrauterine markers of hypoxia, as well as to an adverse outcome; and that development of myocardial dysfunction could be one of the main mechanisms, inducing foetal compromise in poorly controlled gestational diabetes.What are the implications of these findings for clinical practice and/or further research? This study explores an interesting concept of foetal pathophysiology in gestational diabetes, namely the concept of "pseudo-hypoxia" in a foetus of a gestational diabetic mother, and this intrauterine "hypoxic stress" in turn leading to myocardial dysfunction. The Mod-MPI, a clinical marker for cardiac dysfunction, can therefore be used in the clinical setting to track a deteriorating metabolic state.

Association between fetoplacental Doppler results, placental pathology, and angiogenic factors among pregnant women with anxiety.

OBJECTIVE: This study aimed to evaluate whether state and trait anxiety among pregnant women were associated with fetoplacental Doppler findings, abnormal placental pathology, and placental angiogenic factors. MATERIALS AND METHODS: A total of 102 pregnant women at 32-35 gestational weeks were recruited and examined prospectively. State and trait anxiety were measured using the State-Trait Anxiety Inventory. Using Doppler ultrasound, pulsatility index (PI) of the umbilical artery (UA), middle cerebral artery (MCA), and uterine artery (UtA) and cerebroplacental ratio (CPR) were determined. Doppler parameters were converted into multiples of the median (MoM). Abnormal placental pathology was classified into 2 groups: vascular underperfusion (VU) and histological chorioamnionitis (HCA). Immunohistochemical analysis was performed to examine placental cells staining positive for placental growth factor (PLGF) and hypoxia-inducible factor-1-α (HIF-1α), which are markers for angiogenesis and hypoxic status, respectively. RESULTS: Women with high state anxiety scores had low MCA-PI MoM and CPR MoM, while those with high trait anxiety scores had low MCA-PI MoM. VU was associated with a higher incidence of high trait anxiety scores, and HCA was associated with a higher incidence of high state and trait anxiety scores. Regression analysis showed a relationship between maternal state anxiety on MCA-PI MoM and HCA after controlling for covariates. Maternal trait anxiety exhibited relationships with VU and HCA after adjustment. CONCLUSION: Our results demonstrated that maternal anxiety is associated with altered fetal cerebral blood flow and abnormal placental pathology but is not associated with uteroplacental insufficiency and placental angiogenic factors.

Types of intrapartum hypoxia on the cardiotocograph (CTG): do they have any relationship with the type of brain injury in the MRI scan in term babies?

Electronic foetal monitoring using cardiotocography is aimed at the timely recognition and management of foetal hypoxia. The primary objective of this study was to examine whether a relationship exists between the types of foetal hypoxia (acute, subacute, evolving, chronic), as identified on cardiotocography and the nature of hypoxic ischaemic encephalopathy, as observed on MRI scans after birth. We conducted a retrospective study of 16 babies born (out of 52,187 births) at St George's Hospital in London during 2006-2017 with a postnatal diagnosis of HIE. Of the 16 babies, only 11 had both MRI scans and CTG traces available. Of those, 9 showed evidence of intrapartum hypoxia on CTG, but only 6 demonstrated evidence of HIE on MRI. Those with acute hypoxia showed abnormalities in the basal ganglia and thalami. A gradually evolving hypoxia or subacute hypoxia was associated with lesions in myelination and cerebral cortex.Impact StatementWhat is already known on this subject? It has been reported that inter-observer agreement for CTG interpretation is low (30%) when pattern recognition based guidelines are used (Rhöse et al. 2014; Reif et al. 2016), even amongst 'experts' (Hruban et al. 2015). Furthermore, it has been shown that CTG traces do not reliably predict neonatal encephalopathy (Spencer et al. 1997).What do the results of this study add? Our study indicates that if 'types of intrapartum hypoxia' are used for interpretation, then inter-observer agreement increases to 81%, from the reported 30% when traces are classified into 'normal, suspicious and pathological' using guidelines based on 'pattern recognition'. Furthermore, our study shows a good correlation between the type of intrapartum hypoxia observed on CTG trace and the nature of injury observed on the MRI.What are the implications of these findings for clinical practise and/or further research? Improving inter-observer agreement of CTGs with the use of pattern recognition in combination with the good correlation to MRI scan findings ultimately leads to better management and post-natal outcomes. This is evidenced by the fact that after the introduction of physiology-based CTG interpretation and mandatory competency testing on CTG interpretation for all staff in 2010, St. George's Maternity Unit has half the nationally reported rate of cerebral palsy.

Prediction of adverse perinatal outcome by cerebroplacental ratio in women undergoing induction of labor.

OBJECTIVE: To investigate the performance of screening for adverse perinatal outcome by the cerebroplacental ratio (CPR) measured within 24 h prior to induction of labor. METHODS: This was a prospective observational study of 1902 singleton pregnancies undergoing induction of labor at ≥ 37 weeks' gestation. Doppler ultrasound was used to measure the pulsatility index (PI) in the umbilical artery (UA) and fetal middle cerebral artery (MCA) within 24 h before induction of labor. The measured UA-PI and MCA-PI and their ratio were converted to multiples of the median after adjustment for gestational age. Univariable and multivariable logistic regression analysis was used to determine whether CPR improved the prediction of adverse perinatal outcome provided by maternal characteristics, medical history and obstetric factors. The detection rate (DR) and false-positive rate (FPR) of screening by CPR were estimated for Cesarean section for presumed fetal distress and adverse neonatal outcome, which included umbilical arterial or venous cord blood pH ≤ 7 and ≤ 7.1, respectively, 5-min Apgar score < 7, admission to the neonatal intensive care unit for > 24 h or hypoxic ischemic encephalopathy. RESULTS: A combination of maternal and pregnancy characteristics, including age, weight, racial origin, previous obstetric history, pre-eclampsia, gestational age at delivery and amniotic fluid volume, identified 39% of pregnancies requiring Cesarean section for fetal distress at a FPR of 10%; addition of CPR did not improve the performance of screening. In screening for adverse neonatal outcome by a combination of parity and CPR, the DR was 17% at a FPR of 10%. CONCLUSION: Low CPR, measured within 24 h prior to induction of labor, is associated with increased risk of Cesarean section for fetal distress and adverse neonatal outcome, but the performance of CPR for such surrogate measures of fetal hypoxic morbidity is poor. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Prognostic model based on image-based time-frequency features and genetic algorithm for fetal hypoxia assessment.

Cardiotocography (CTG) is applied routinely for fetal monitoring during the perinatal period to decrease the rates of neonatal mortality and morbidity as well as unnecessary interventions. The analysis of CTG traces has become an indispensable part of present clinical practices; however, it also has serious drawbacks, such as poor specificity and variability in its interpretation. The automated CTG analysis is seen as the most promising way to overcome these disadvantages. In this study, a novel prognostic model is proposed for predicting fetal hypoxia from CTG traces based on an innovative approach called image-based time-frequency (IBTF) analysis comprised of a combination of short time Fourier transform (STFT) and gray level co-occurrence matrix (GLCM). More specifically, from a graphical representation of the fetal heart rate (FHR) signal, the spectrogram is obtained by using STFT. The spectrogram images are converted into 8-bit grayscale images, and IBTF features such as contrast, correlation, energy, and homogeneity are utilized for identifying FHR signals. At the final stage of the analysis, different subsets of the feature space are applied as the input to the least square support vector machine (LS-SVM) classifier to determine the most informative subset. For this particular purpose, the genetic algorithm is employed. The prognostic model was performed on the open-access intrapartum CTU-UHB CTG database. The sensitivity and specificity obtained using only conventional features were 57.33% and 67.24%, respectively, whereas the most effective results were achieved using a combination of conventional and IBTF features, with a sensitivity of 63.45% and a specificity of 65.88%. Conclusively, this study provides a new promising approach for feature extraction of FHR signals. In addition, the experimental outcomes showed that IBTF features provided an increase in the classification accuracy.

Ultrasonographic prediction of antepartum deterioration of growth-restricted fetuses after late preterm.

AIM: To examine the predictive value of ultrasound parameters for antepartum non-reassuring fetal status (NRFS) in fetal growth restriction (FGR) cases after late preterm. METHODS: Retrospective review of singleton FGR cases before 37 weeks gestation who delivered after 34 weeks gestation was performed. The association between ultrasound parameters that was assessed from 34 to 36 weeks gestation and the development of antepartum NRFS that was diagnosed by nonstress test and biophysical profile was analyzed by using multivariate Cox proportional hazards analyses. RESULTS: A total of 214 patients were included in final data analyses. Antepartum NRFS occurred in 23 cases (10.7%) including five cases of placental abruption. Lower standard deviation (SD) of estimated fetal weight (EFW), lower cerebroplacental ratio (CPR) and the presence of oligohydramnios were independently associated with antepartum NRFS. The prevalence of antepartum NRFS was highest (50.4%) in the group of EFW ≤-2.5 SD with CPR ≤1.45. CONCLUSION: Ultrasound parameters of lower SD of EFW, lower CPR and oligohydramnios were predictive for antepartum NRFS in FGR after late preterm.

Papel do Doppler do ducto venoso na restrição de crescimento intrauterino / Ductus venosus Doppler assessment in intrauterine growth restriction

Objetivo: O crescimento intrauterino restrito (CIUR) por insuficiência placentária persiste como grande desafio obstétrico. A interrupção da gestação representa a única estratégia de condução e baseia-se na predição de desfechos adversos. O Doppler tem valor reconhecido na avaliação seriada das alterações circulatórias nesses fetos, em geral sequenciais e proporcionais à gravidade do insulto hipóxico. Este estudo objetiva revisar as evidências do papel do Doppler de ducto venoso (DV) na predição de morbimortalidade perinatal em gestações complicadas por CIUR placentário grave e precoce. Métodos: Realizou-se revisão narrativa, com busca de artigos publicados nos últimos 10 anos nas bases Medline/PubMed, Lilacs e Scielo, sendo encontradas 132 referências. Pesquisas com animais e gestações múltiplas foram excluídas. Dos 115 artigos selecionados, 34 foram excluídos por inadequação ao tema. A revisão baseou-se nas demais 81 referências, além de trabalhos de reconhecida relevância no tema. Resultados: Estudos demonstram evidência consistente do papel do Doppler de DV na avaliação de fetos com CIUR, com bom valor preditivo para acidemia fetal e desfecho perinatal adverso. As principais estratégias de monitorização se baseiam na combinação do Doppler de vasos arteriais/venosos e parâmetros biofísicos, mas o Doppler de DV seria o melhor parâmetro isolado para predição de comprometimento fetal grave. Conclusão: A incorporação do Doppler de DV na monitorização de fetos com CIUR grave e precoce é capaz de predizer desfechos perinatais críticos. A avaliação de múltiplos vasos fetais parece aumentar a acurácia, porém não há evidência para embasar a definição de protocolos para o manejo clínico.(AU)

Objective: Intrauterine growth restriction (IUGR) due to early onset placental insufficiency remains to be a great challenge in obstetrical practice. Delivery is still the only available strategy of management, and timing such intervention depends on prediction of adverse outcomes. Dopplervelocimetry studies have recognized value in the evaluation of the sequential hemodynamic changes that are stablished in the arterial and venous circulation of these fetuses, which correlate with the severity of hypoxemic insult. This study aims to review evidence on ductus venosus (DV) Doppler`s role as a predictor of perinatal outcome in pregnancies complicated by severe early onset IUGR. Methods: A Medline/PubMed, Lilacs and Scielo search was performed to identify original articles and systematic reviews published in the last 10 years. Eighty-one references were included in this review, in addition to other papers of recognized relevance in the subject. Results: Studies demonstrate consistent evidence on DV Doppler`s role in the longitudinal evaluation of IUGR fetuses, with adequate predictive value for fetal acidemia and adverse outcome. Monitoring strategies are usually based on a combination of arterial and venous Doppler assessment, in addition to biophysical parameters, but DV Doppler seems to be the best single parameter for prediction of severe fetal compromise. Conclusion: Monitoring of fetuses with severe early-onset IUGR through DV Doppler is able to predict critical perinatal outcomes. Evaluation of multiple fetal vessels seems to increase accuracy of prediction, but to this moment there is not enough evidence to recommend protocols of management.(AU)

Is cerebroplacental ratio a marker of impaired fetal growth velocity and adverse pregnancy outcome?

BACKGROUND: The cerebroplacental ratio has been proposed as a marker of failure to reach growth potential near term. Low cerebroplacental ratio, regardless of the fetal size, is independently associated with the need for operative delivery for presumed fetal compromise and with neonatal unit admission at term. OBJECTIVE: The main aim of this study was to evaluate whether the cerebroplacental ratio at term is a marker of reduced fetal growth rate. The secondary aim was to investigate the relationship between a low cerebroplacental ratio at term, reduced fetal growth velocity, and adverse pregnancy outcome. STUDY DESIGN: This was a retrospective cohort study of singleton pregnancies in a tertiary referral center. The abdominal circumference was measured at 20-24 weeks' gestation and both abdominal circumference and fetal Dopplers recorded at or beyond 35 weeks, within 2 weeks of delivery. Abdominal circumference and birthweight values were converted into Z scores and centiles, respectively, and fetal Doppler parameters into multiples of median, adjusting for gestational age. Abdominal circumference growth velocity was quantified using the difference in the abdominal circumference Z score, comparing the scan at or beyond 35 weeks with the scan at 20-24 weeks. Both univariable and multivariable logistic regression analyses were performed to investigate the association between low cerebroplacental ratio and the low abdominal circumference growth velocity (in the lowest decile) and to identify and adjust for potential confounders. As a sensitivity analysis, we refitted the model excluding the data on pregnancies with small-for-gestational-age neonates. RESULTS: The study included 7944 pregnancies. Low cerebroplacental ratio multiples of median was significantly associated with both low abdominal circumference growth velocity (adjusted odds ratio, 2.10; 95% confidence interval, 1.71-2.57, P <0.001) and small for gestational age (adjusted odds ratio, 3.60; 95% confidence interval, 3.04-4.25, P < .001). After the exclusion of pregnancies resulting in small-for-gestational-age neonates, a low cerebroplacental ratio multiples of the median remained significantly associated with both low abdominal circumference growth velocity (adjusted odds ratio, 1.76; 95% confidence interval, 1.34-2.30, P < .001) and birthweight centile (adjusted odds ratio, 0.99; 95% confidence interval, 0.998-0.995, P < .001). The need for operative delivery for fetal compromise was significantly associated with a low cerebroplacental ratio (adjusted odds ratio, 1.40; 95% confidence interval, 1.10-1.78, P = .006), even after adjusting for both the umbilical artery pulsatility index multiples of the median and middle cerebral artery pulsatility index multiples of median. The results were similar, even after the exclusion of pregnancies resulting in small-for-gestational-age neonates (adjusted odds ratio, 1.39; 95% confidence interval, 1.06-1.84, P = .018). Low cerebroplacental ratio multiples of the median remained significantly associated with the risk of operative delivery for presumed fetal compromise (P < .001), even after adjusting for the known antenatal and intrapartum risk factors. These associations persisted, even after the exclusion of small-for-gestational-age births. In appropriate-for-gestational-age-sized fetuses, abdominal circumference growth velocity was significantly lower in those with a low cerebroplacental ratio multiples of the median than in those with normal cerebroplacental ratio multiples of the median (P < .001). CONCLUSION: The cerebroplacental ratio is a marker of impaired fetal growth velocity and adverse pregnancy outcome, even in fetuses whose size is considered appropriate using conventional biometry.

Early onset fetal growth restriction.

Fetal growth restriction remains a challenging entity with significant variations in clinical practice around the world. The different etiopathogenesis of early and late fetal growth restriction with their distinct progression of fetal severity and outcomes, compounded by doctors and patient anxiety adds to the quandary involving its management. This review summarises the literature around diagnosing and monitoring early onset fetal growth restriction (early onset FGR) with special emphasis on optimal timing of delivery as guided by recent research advances.

Robust Wavelet Stabilized 'Footprints of Uncertainty' for Fuzzy System Classifiers to Automatically Detect Sharp Waves in the EEG after Hypoxia Ischemia.

Currently, there are no developed methods to detect sharp wave transients that exist in the latent phase after hypoxia-ischemia (HI) in the electroencephalogram (EEG) in order to determine if these micro-scale transients are potential biomarkers of HI. A major issue with sharp waves in the HI-EEG is that they possess a large variability in their sharp wave profile making it difficult to build a compact 'footprint of uncertainty' (FOU) required for ideal performance of a Type-2 fuzzy logic system (FLS) classifier. In this paper, we develop a novel computational EEG analysis method to robustly detect sharp waves using over 30[Formula: see text]h of post occlusion HI-EEG from an equivalent, in utero, preterm fetal sheep model cohort. We demonstrate that initial wavelet transform (WT) of the sharp waves stabilizes the variation in their profile and thus permits a highly compact FOU to be built, hence, optimizing the performance of a Type-2 FLS. We demonstrate that this method leads to higher overall performance of [Formula: see text] for the clinical [Formula: see text] sampled EEG and [Formula: see text] for the high resolution [Formula: see text] sampled EEG that is improved upon over conventional standard wavelet [Formula: see text] and [Formula: see text], respectively, and fuzzy approaches [Formula: see text] and [Formula: see text], respectively, when performed in isolation.

In Vivo Neurochemical Characterization of Developing Guinea Pigs and the Effect of Chronic Fetal Hypoxia.

The guinea pig is a frequently used animal model for human pregnancy complications, such as oxygen deprivation or hypoxia, which result in altered brain development. To investigate the impact of in utero chronic hypoxia on brain development, pregnant guinea pigs underwent either normoxic or hypoxic conditions at about 70 % of 65-day term gestation. After delivery, neurochemical profiles consisting of 19 metabolites and macromolecules were obtained from the neonatal cortex, hippocampus, and striatum from birth to 12 weeks postpartum using in vivo (1)H MR spectroscopy at 9.4 T. The effects of chronic fetal hypoxia on the neurochemical profiles were particularly significant at birth. However, the overall developmental trends of neurochemical concentration changes were similar between normoxic and hypoxic animals. Alterations of neurochemicals including N-acetylaspartate (NAA), phosphorylethanolamine, creatine, phosphocreatine, and myo-inositol indicate neuronal loss, delayed myelination, and altered brain energetics due to chronic fetal hypoxia. These observed neurochemical alterations in the developing brain may provide insights into hypoxia-induced brain pathology, neurodevelopmental compromise, and potential neuroprotective measures.

Neonatal Acid-Base Status in Term Fetuses: Mathematical Models Investigating Cerebroplacental Ratio and Birth Weight.

OBJECTIVE: Cerebroplacental ratio (CPR) is emerging as a marker of fetal hypoxia at term. The aim of this study was to demonstrate graphically the interrelationships among CPR, birthweight (BW), and neonatal pH, and construct 2D and 3D representations of the areas with potential low pH. METHODS: This was a retrospective study of 2,927 term fetuses evaluated according to BW and CPR. The outcome was the acid-base status at birth. Multivariate relationships among CPR, BW, and arterial and venous pH were depicted in 3D scattergrams. Subsequently, trend surfaces were calculated and represented in 2D contour graphs. Finally, 3D representations were constructed by smothering pH data using moving average filters. RESULTS: The trend surfaces and the 2D and 3D contour graphs showed the complex association among the three variables. Although pH changed with CPR and BW, the influence of the BW was smaller than the influence of the CPR, with this effect being more evident in the venous than in the arterial pH. CONCLUSIONS: Two scenarios threaten fetal well-being at term: a very low birth weight and a very low fetal CPR. Our findings suggest that the importance of fetal hemodynamics in determining the acid-base status at birth surpasses that of fetal weight.

[The asphyxia of the fetus--cardiotocography and ultrasound methods of diagnosis].

The asphyxia of the fetus remains a main cause for neonatal morbility and mortality. And the possibility of it developing antenatal or intrapartal. The main objective of the antenatal fetus examination tests is the timely diagnosis of the signs of the asphyxia of the fetus.

Brain sparing in fetal mice: BOLD MRI and Doppler ultrasound show blood redistribution during hypoxia.

Mice reproduce many features of human pregnancy and have been widely used to model disorders of pregnancy. However, it has not been known whether fetal mice reproduce the physiologic response to hypoxia known as brain sparing, where blood flow is redistributed to preserve oxygenation of the brain at the expense of other fetal organs. In the present study, blood oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) and Doppler ultrasound were used to determine the effect of acute hypoxia on the fetal blood flow in healthy, pregnant mice. As the maternal inspired gas mixture was varied between 100% and 8% oxygen on the timescale of minutes, the BOLD signal intensity decreased by 44±18% in the fetal liver and by 12±7% in the fetal brain. Using Doppler ultrasound measurements, mean cerebral blood velocity was observed to rise by 15±8% under hypoxic conditions relative to hyperoxia. These findings are consistent with active regulation of cerebral oxygenation and clearly show brain sparing in fetal mice.

Assessment of motoric and hemodynamic parameters in growth restricted fetuses - case study.

OBJECTIVE: In order to more accurately assess fetal neurological status in five fetuses with severe intrauterine growth restriction (IUGR), combined assessment of their hemodynamics and motor activity was undertaken in this study. METHOD: Hemodynamic changes in the placental and fetal cerebral vessels were evaluated using the umbilical artery resistance index (URI), and the middle cerebral artery resistance index (CRI). The blood flow redistribution towards the fetal brain in response to fetal hypoxia was detected by the C/U (cerebro - umbilical) ratio, expressed as CRI/URI. Motoric parameters were assessed by new antenatal neurologic scoring test named Kurjak Antenatal Neurodevelopmental Test (KANET), based on evaluation of spontaneous motor activity using four-dimensional (4D) ultrasound. RESULTS: KANET has potential in recognizing pathologic and borderline behavior in IUGR fetuses with or without blood flow redistribution towards the fetal brain. Very low values of C/U ratio and abnormal KANET score have indicated adverse pregnancy outcome. CONCLUSION: In some pregnancies complicated with IUGR, estimation of the risk of hypoxia versus prematurity can be extremely puzzling. Combined assessment of hemodynamic and motoric parameters in IUGR fetuses could allow construction of an algorithm, which would be helpful in the decision making process of pregnancy termination.

Cardiac function in early onset small for gestational age and growth restricted fetuses.

OBJECTIVE: To examine cardiac function in appropriately grown, small for gestational age and intrauterine growth restricted fetuses and investigate the relationship between cardiac function and fetal arterial and venous Doppler parameters. STUDY DESIGN: Myocardial performance index, isovolumetric contraction time, isovolumetric relaxation time, ejection time, and umbilical artery, middle cerebral artery and ductus venosus Doppler pulsatility index were measured for women between 24 and 32 weeks with small for gestational age and intrauterine growth restricted fetuses. Forty-eight appropriately grown, 11 small for gestational age and 12 intrauterine growth restricted cases were included. The relationship between cardiovascular parameters and gestation was defined and Doppler values converted to Z-scores in relation to gestational age. RESULTS: In small for gestational age fetuses and fetuses with intrauterine growth restriction the myocardial performance index was 0.66 (0.63-0.7) and 0.64 (0.60-0.67), respectively, and compared to appropriately grown fetuses, at 0.45 (0.43-0.47), was significantly increased (p=0.001). No relationship was found between the myocardial performance index and arterial and venous Doppler Z-score. CONCLUSION: Small for gestational age and intrauterine growth restricted fetuses demonstrate altered cardiac function in the late second and early third trimester of pregnancy. Importantly, the myocardial performance index is raised in small for gestational age fetuses before the arterial and venous Doppler abnormalities that characterize hypoxia are evident.