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1.
J Vis Exp ; (167)2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33491675

RESUMO

Magnetic resonance imaging (MRI) is an important tool for the clinical assessment of cardiovascular morphology and heart function. It is also the recognized standard-of-care for blood flow quantification based on phase contrast MRI. While such measurement of blood flow has been possible in adults for decades, methods to extend this capability to fetal blood flow have only recently been developed. Fetal blood flow quantification in major vessels is important for monitoring fetal pathologies such as congenital heart disease (CHD) and fetal growth restriction (FGR). CHD causes alterations in the cardiac structure and vasculature that change the course of blood in the fetus. In FGR, the path of blood flow is altered through the dilation of shunts such that the oxygenated blood supply to the brain is increased. Blood flow quantification enables assessment of the severity of the fetal pathology, which in turn allows for suitable in utero patient management and planning for postnatal care. The primary challenges of applying phase contrast MRI to the human fetus include small blood vessel size, high fetal heart rate, potential MRI data corruption due to maternal respiration, unpredictable fetal movements, and lack of conventional cardiac gating methods to synchronize data acquisition. Here, we describe recent technical developments from our lab that have enabled the quantification of fetal blood flow using phase contrast MRI, including advances in accelerated imaging, motion compensation, and cardiac gating.


Assuntos
Circulação Sanguínea/fisiologia , Sangue Fetal/fisiologia , Imagem por Ressonância Magnética , Movimento (Física) , Adulto , Aorta/fisiologia , Feminino , Feto/fisiologia , Frequência Cardíaca Fetal/fisiologia , Hemodinâmica , Humanos , Gravidez , Reprodutibilidade dos Testes , Sístole/fisiologia
2.
PLoS One ; 15(8): e0236982, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745099

RESUMO

BACKGROUND: Continuous intrapartum fetal monitoring is challenging and its clinical benefits are debated. The project evaluated whether short-term-variation (STV) and other computerised fetal heart rate (FHR) parameters (baseline FHR, long-term-variation, accelerations and decelerations) predicted acidaemia at birth. The aims of the study were to assess the changes in FHR pattern during labour and determine the feasibility of undertaking a definitive trial by reporting the practicalities of using the monitoring device, participant recruitment, data collection and staff training. METHODS: 200 high-risk women carrying a term singleton, non-anomalous fetus, requiring continuous FHR monitoring in labour were consented to participate from the Jessop Wing maternity unit, Sheffield, UK. The trans-abdominal fetal ECG monitor was placed as per clinical protocol. During the monitoring session, clinicians were blinded to the computerised FHR parameters. We analysed the last hour of the FHR and its ability to predict umbilical arterial blood pH <7.20 using receiver operator characteristics (ROC) curves. RESULTS: Of 200 women, 137 cases were excluded as either the monitor did not work from the onset of labour (n = 30), clinical staff did not return or used the monitor on another patient (n = 37), umbilical cord blood not obtained (n = 25), FHR data not recorded within an hour of birth (n = 34) and other reasons (n = 11). In 63 cases included in the final analysis, the computer-derived FHR parameters did not show significant correlation with umbilical artery cord pH <7.20. Labour was associated with a significant increase in short and long term variation of FHR and number of deceleration (P<0.001). However, baseline FHR decreased significantly before delivery (P<0.001). CONCLUSIONS: The project encountered a number of challenges, with learning points crucial to informing the design of a large study to evaluate the potential place of intrapartum computerised FHR parameters, using abdominal fetal ECG monitor before its clinical utility and more widespread adoption can be ascertained.


Assuntos
Eletroencefalografia/instrumentação , Monitorização Fetal/métodos , Frequência Cardíaca Fetal/fisiologia , Acidose/fisiopatologia , Adulto , Cardiotocografia , Eletrocardiografia , Estudos de Viabilidade , Feminino , Sangue Fetal , Doenças Fetais/fisiopatologia , Feto/fisiopatologia , Humanos , Concentração de Íons de Hidrogênio , Trabalho de Parto , Gravidez
3.
Am J Physiol Regul Integr Comp Physiol ; 319(1): R123-R131, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32491938

RESUMO

Fetal heart rate (FHR) variability (FHRV) and ST segment morphology are potential clinical indices of fetal well-being during labor. ß-Adrenergic stimulation by circulating catecholamines has been hypothesized to contribute to both FHRV and ST segment morphology during labor, but this has not been tested during brief repeated fetal hypoxemia that is characteristic of labor. Near-term fetal sheep (0.85 gestation) received propranolol (ß-adrenergic blockade; n = 10) or saline (n = 7) 30 min before being exposed to three 2-min complete umbilical cord occlusions (UCOs) separated by 3-min reperfusions. T/QRS ratio was calculated throughout UCOs and reperfusion periods, and measures of FHRV (RMSSD, SDNN, and STV) were calculated between UCOs. During the baseline period, before the start of UCOs, propranolol was associated with reduced FHR, SDNN, and STV but did not affect RMSSD or T/QRS ratio. UCOs were associated with rapid FHR decelerations and increased T/QRS ratio; propranolol significantly reduced FHR during UCOs and was associated with a slower rise in T/QRS ratio during the first UCOs, without affecting the maximal rise or T/QRS ratio during the second and third UCO. Between UCOs propranolol reduced FHR and T/QRS ratio but did not affect any measure of FHRV. These data demonstrate that circulating catecholamines do not contribute to FHRV during labor-like hypoxemia. Furthermore, circulating catecholamines did not contribute to the major rise in T/QRS ratio during labor-like hypoxemia but may regulate T/QRS ratio between brief hypoxemia.


Assuntos
Catecolaminas/fisiologia , Frequência Cardíaca Fetal/fisiologia , Carneiro Doméstico/fisiologia , Cordão Umbilical/fisiologia , Agonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/farmacologia , Adulto , Animais , Catecolaminas/sangue , Eletrocardiografia , Feminino , Hipóxia Fetal/fisiopatologia , Humanos , Hipóxia/fisiopatologia , Trabalho de Parto , Gravidez , Propranolol/farmacologia
4.
PLoS One ; 15(4): e0232606, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32353083

RESUMO

INTRODUCTION: The examination of the fetal heart in mid-pregnancy is by ultrasound examination. The quality of the examination is highly dependent on the skill of the sonographer, fetal position and maternal body mass index. An additional tool that is less dependent on human experience and interpretation is desirable. The fetal electrocardiogram (ECG) could fulfill this purpose. We aimed to show the feasibility of recording a standardized fetal ECG in mid-pregnancy and explored its possibility to detect congenital heart disease (CHD). MATERIALS AND METHODS: Women older than 18 years of age with an uneventful pregnancy, carrying a healthy singleton fetus with a gestational age between 18 and 24 weeks were included. A fetal ECG was performed via electrodes on the maternal abdomen. After removal of interferences, a vectorcardiogram was constructed. Based on the ultrasound assessment of the fetal orientation, the vectorcardiogram was rotated to standardize for fetal orientation and converted into a 12-lead ECG. Median ECG waveforms for each lead were calculated. RESULTS: 328 fetal ECGs were recorded. 281 were available for analysis. The calculated median ECG waveform showed the electrical heart axis oriented to the right and inferiorly i.e. a negative QRS deflection in lead I and a positive deflection in lead aVF. The two CHD cases show ECG abnormalities when compared to the mean ECG of the healthy cohort. DISCUSSION: We have presented a method for estimating a standardized 12-lead fetal ECG. In mid-pregnancy, the median electrical heart axis is right inferiorly oriented in healthy fetuses. Future research should focus on fetuses with congenital heart disease.


Assuntos
Eletrocardiografia/normas , Coração Fetal/fisiologia , Cardiopatias Congênitas/diagnóstico , Diagnóstico Pré-Natal/métodos , Adulto , Estudos de Casos e Controles , Estudos Transversais , Eletrocardiografia/instrumentação , Estudos de Viabilidade , Feminino , Idade Gestacional , Cardiopatias Congênitas/fisiopatologia , Frequência Cardíaca Fetal/fisiologia , Humanos , Lactente , Países Baixos , Projetos Piloto , Gravidez , Segundo Trimestre da Gravidez , Valores de Referência
5.
Artigo em Inglês | MEDLINE | ID: mdl-32360366

RESUMO

The second stage of labor, from full cervical dilatation to complete birth of the baby or babies, constitutes the time of greatest risk for the baby. Birth attendants at all levels require training in the skills necessary to overcome difficulties that may arise unexpectedly during the second stage, particularly poor progress, shoulder dystocia, and breech birth. The mother should receive emotional support and encouragement to bear down instinctively when she feels the urge to do so, in the position she feels enables her to push most effectively, but not the supine position. The baby's heart rate should be monitored after every second contraction. Recent guidelines such as those of the World Health Organization(WHO) recommend allowing 2-3 h for the second stage of labor. Uterine fundal pressure has not been shown to be effective, and may be dangerous. Choosing between cesarean section and assisted vaginal birth to overcome delayed second stage requires relevant skill and experience.


Assuntos
Cesárea , Distocia , Frequência Cardíaca Fetal/fisiologia , Segunda Fase do Trabalho de Parto/fisiologia , Distocia/prevenção & controle , Feminino , Humanos , Parto , Gravidez
6.
Artigo em Inglês | MEDLINE | ID: mdl-32299728

RESUMO

Continuous electronic fetal monitoring (EFM) was first introduced commercially over 50 years ago with the hope of improving perinatal outcomes during labor. However, despite the increased use of EFM, definitive improvements in perinatal outcomes have not been demonstrated. Variance in tracing interpretation and intervention has led to increased rates of cesarean and operative vaginal deliveries and perhaps increased maternal and neonatal morbidity. Since its inception, several strategies have been developed in hopes of optimizing EFM and improving these outcomes. We discuss the current standards of intrapartum fetal monitoring and review optimization strategies and technologies in development to improve intrapartum fetal monitoring.


Assuntos
Cardiotocografia , Frequência Cardíaca Fetal/fisiologia , Trabalho de Parto , Parto Obstétrico , Feminino , Monitorização Fetal , Humanos , Gravidez
7.
PLoS One ; 15(2): e0229568, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32101584

RESUMO

OBJECTIVE: To determine whether the presence of co-existing sleep-disordered breathing (SDB) is associated with worse perinatal outcomes among women diagnosed with a hypertensive disorder of pregnancy (HDP), compared with normotensive controls. STUDY DESIGN: Women diagnosed with HDP (gestational hypertension or preeclampsia) and BMI- and gestation-matched controls underwent polysomnography in late pregnancy to determine if they had coexisting SDB. Fetal heart rate (FHR) monitoring accompanied the sleep study, and third trimester fetal growth velocity was assessed using ultrasound. Cord blood was taken at delivery to measure key regulators of fetal growth. RESULTS: SDB was diagnosed in 52.5% of the HDP group (n = 40) and 38.1% of the control group (n = 42); p = .19. FHR decelerations were commonly observed during sleep, but the presence of SDB did not increase this risk in either the HDP or control group (HDP group-SDB = 35.3% vs. No SDB = 40.0%, p = 1.0; control group-SDB = 41.7% vs. No SDB = 25.0%, p = .44), nor did SDB affect the total number of decelerations overnight (HDP group-SDB = 2.7 ± 1.0 vs. No SDB = 2.8 ± 2.1, p = .94; control group-SDB = 2.0 ± 0.8 vs. No SDB = 2.0 ± 0.7, p = 1.0). Fetal growth restriction was the strongest predictor of fetal heart rate events during sleep (aOR 5.31 (95% CI 1.26-22.26), p = .02). The presence of SDB also did not adversely affect fetal growth; in fact among women with HDP, SDB was associated with significantly larger customised birthweight centiles (43.2% ± 38.3 vs. 16.2% ± 27.0, p = .015) and fewer growth restricted babies at birth (30% vs. 68.4%, p = .026) compared to HDP women without SDB. There was no impact of SDB on measures of fetal growth for the control group. Cord blood measures of fetal growth did not show any adverse effect among women with SDB, either in the HDP or control group. CONCLUSION: We did not find that the presence of mild SDB worsened fetal acute or longitudinal outcomes, either among women with HDP or BMI-matched normotensive controls. Unexpectedly, we found the presence of SDB conferred a better prognosis in HDP in terms of fetal growth. The fetus has considerable adaptive capacity to withstand in utero hypoxia, which may explain our mostly negative findings. In addition, SDB in this cohort was mostly mild. It may be that fetal sequelae will only be unmasked in the setting of more severe degrees of SDB and/or underlying placental disease.


Assuntos
Hipertensão Induzida pela Gravidez/fisiopatologia , Resultado da Gravidez/epidemiologia , Síndromes da Apneia do Sono/fisiopatologia , Adulto , Austrália , Peso ao Nascer , Estudos de Coortes , Feminino , Desenvolvimento Fetal/fisiologia , Retardo do Crescimento Fetal/metabolismo , Frequência Cardíaca Fetal/fisiologia , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional/metabolismo , Recém-Nascido Pequeno para a Idade Gestacional/fisiologia , Parto/fisiologia , Polissonografia , Pré-Eclâmpsia/fisiopatologia , Gravidez , Complicações na Gravidez/fisiopatologia , Terceiro Trimestre da Gravidez , Estudos Prospectivos , Síndromes da Apneia do Sono/complicações
8.
Glob Health Action ; 13(1): 1711618, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31955672

RESUMO

Background: In Uganda, perinatal mortality is 38 per 1000 pregnancies. One-third of these deaths are due to birth asphyxia. Adequate fetal heart rate (FHR) monitoring during labor may detect birth asphyxia but little is known about monitoring practices in low resource settings.Objective: To explore FHR monitoring practices among health workers at a public hospital in Northern Uganda.Methods: A sequential explanatory mixed methods study was conducted by reviewing 251 maternal records and conducting 11 interviews and two focus group discussions with health workers complemented by observations of 42 women in labor until delivery. Quantitative data were summarized using frequencies and percentages. Content analysis was used for qualitative data.Results: FHR was assessed in 235/251 (93.6%) of records at admission. Health workers documented the FHR at least once in 175/228 (76.8%) of cases during the first stage of labor compared to observed 17/25 (68.0%) cases. Median intervals between FHR monitoring were 30 (IQR 30-120) minutes in patients' records versus 139 (IQR 87-662) minutes according to observations. Observations suggested no monitoring of FHR during the second stage of labor but records indicated monitoring in 3.2% of cases. Reported barriers to adequate FHR monitoring were inadequate number of staff and monitoring devices, institutional challenges such as few beds, documentation problems and perceived non-compliant women not reporting for repeated checks during the first stage of labor. Health workers demonstrated knowledge of national FHR monitoring guidelines and acknowledged that practice was different.Conclusions: When compared to national and international guidelines, FHR monitoring is sub-optimal in the studied setting. Approximately one in four women was not monitored during the first stage of labor. Barriers to appropriate FHR monitoring included shortage of staff and devices, institutional challenges and mother's negative attitudes. These barriers need to be addressed in order to reduce neonatal mortality.


Assuntos
Monitorização Fetal/normas , Mão de Obra em Saúde/estatística & dados numéricos , Frequência Cardíaca Fetal/fisiologia , Hospitais Públicos/estatística & dados numéricos , Trabalho de Parto/fisiologia , Feminino , Fidelidade a Diretrizes , Pessoal de Saúde , Humanos , Lactente , Recém-Nascido , Entrevistas como Assunto , Guias de Prática Clínica como Assunto , Gravidez , Uganda
9.
Int J Gynaecol Obstet ; 149(1): 82-87, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31912893

RESUMO

OBJECTIVE: To assess the effects of maternal position on maternal and fetal heart rate and heart rate variability (HRV) in healthy late gestation pregnancies using non-invasive techniques during overnight studies. METHODS: In an observational study of women between 34 and 36 weeks of pregnancy conducted from September 1, 2013, to March 31, 2014, at Columbia University Medical Center, New York, US, maternal and fetal ECG recordings and position monitoring were undertaken through the night in the woman's own home. These data were used for time domain analyses of fetal and maternal heart rate and HRV. RESULTS: Forty-two women were recruited to the study which showed that maternal position affected maternal heart rate (MHR), with left side sleeping associated with lower heart rate (left vs right P=0.017, left vs supine P=0.027) and higher overall HRV (left vs right P=0.032). MHR showed significant overnight changes (P=0.032). No significant positional or overnight effects were observed in fetal heart rate patterns. CONCLUSION: This study uniquely incorporated analyses on maternal and fetal physiology and extended the knowledge of effects of maternal overnight sleep position on MHR in the natural sleep environment.


Assuntos
Frequência Cardíaca Fetal/fisiologia , Frequência Cardíaca/fisiologia , Postura/fisiologia , Sono/fisiologia , Adulto , Eletrocardiografia , Feminino , Humanos , Gravidez , Terceiro Trimestre da Gravidez , Adulto Jovem
10.
Dev Psychobiol ; 62(2): 224-231, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31127614

RESUMO

Researchers have reported associations between fetal sex and heart rate (FHR) and heart rate variability (FHRV) but rarely in the context of fetal behavioral sleep state. We examined differences in measures of fetal autonomic function by sex and sleep state. Fetal abdominal ECG monitoring technology was used to measure FHR and two measures of FHRV-standard deviation of FHR (SD) and beat-to-beat variability (RMSSD). FHR and movement patterns were also recorded with standard Doppler ultrasound monitor technology employed to code sleep states. Data were collected from 82 healthy fetuses ranging from 36 to 39 weeks gestation. A one-way MANOVA showed that FHR was significantly lower and SD was significantly higher for males than females. Independent samples t tests found that these sex differences were only in the active sleep state. There were no significant differences in RMSSD by sex. Repeated measures MANOVA for a subset that exhibited more than one state (N = 22) showed that SD was significantly different by state. RMSSD showed a marginally significant sleep state difference. In conclusion, fetal sex differences in HR and HRV may indicate more mature autonomic functioning in near-term males than females and fetal sleep state can influence abdominal fECG derived measures of FHR and FHRV.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Feto/fisiologia , Frequência Cardíaca Fetal/fisiologia , Caracteres Sexuais , Sono/fisiologia , Eletrocardiografia , Feminino , Monitorização Fetal , Idade Gestacional , Humanos , Masculino , Gravidez , Terceiro Trimestre da Gravidez , Ultrassonografia Doppler
11.
IEEE Rev Biomed Eng ; 13: 51-73, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31478873

RESUMO

Fetal electrocardiography (fECG) is a promising alternative to cardiotocography continuous fetal monitoring. Robust extraction of the fetal signal from the abdominal mixture of maternal and fetal electrocardiograms presents the greatest challenge to effective fECG monitoring. This is mainly due to the low amplitude of the fetal versus maternal electrocardiogram and to the non-stationarity of the recorded signals. In this review, we highlight key developments in advanced signal processing algorithms for non-invasive fECG extraction and the available open access resources (databases and source code). In particular, we highlight the advantages and limitations of these algorithms as well as key parameters that must be set to ensure their optimal performance. Improving or combining the current or developing new advanced signal processing methods may enable morphological analysis of the fetal electrocardiogram, which today is only possible using the invasive scalp electrocardiography method.


Assuntos
Eletrocardiografia , Coração Fetal/diagnóstico por imagem , Monitorização Fetal , Processamento de Sinais Assistido por Computador , Algoritmos , Feminino , Frequência Cardíaca Fetal/fisiologia , Humanos , Gravidez
12.
J Perinatol ; 40(1): 56-62, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31578422

RESUMO

OBJECTIVE: Investigate marked variability in fetal heart rate (FHR) patterns before delivery and its association with neonatal morbidity and abnormal arterial cord gases. STUDY DESIGN: Prospective cohort of laboring patients at term. Composite neonatal morbidity (respiratory distress, mechanical ventilation, suspected sepsis, meconium aspiration syndrome, therapeutic hypothermia, hypoxic-ischemic encephalopathy, seizure, and death) and abnormal arterial cord gases (pH < 7.10, lactate ≥ 4 mmol/L, base deficit < -12 mEq/L) were assessed with multivariable logistic regression. RESULT: Three hundred and ninety (4.5%) neonates had marked variability in FHR patterns before delivery. There was no difference in composite neonatal morbidity (aRR 1.22; 95% CI 0.91-1.63), though neonates with marked variability in FHR patterns were more likely to have a respiratory distress (aRR 1.85; 95% CI 1.25-2.70). There was an increased risk of composite abnormal arterial cord gases (aRR 1.66; 95% CI 1.47-1.88). CONCLUSION: Marked variability in FHR patterns was not associated with composite neonatal morbidity but was associated with abnormal arterial cord gases.


Assuntos
Dióxido de Carbono/análise , Sangue Fetal/química , Frequência Cardíaca Fetal/fisiologia , Doenças do Recém-Nascido/epidemiologia , Ácido Láctico/sangue , Bicarbonatos/sangue , Gasometria , Eletrocardiografia , Monitorização Fetal , Humanos , Recém-Nascido , Doenças do Recém-Nascido/mortalidade , Estudos Prospectivos
13.
Z Geburtshilfe Neonatol ; 224(1): 26-30, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30974475

RESUMO

INTRODUCTION: Antenatal betamethasone administration in the context of foetal lung maturity enhancement has a transient impact on the short-term variation (STV) of the foetal heart rate. There are currently various algorithms for computing the STV, each one resulting in different STV values. We studied the results of betamethasone administration on the STV using 2 different algorithms in order to investigate whether the effects of steroids on the STV depend on the algorithm used or not. MATERIALS AND METHODS: In the context of a larger, single-centre, prospective, observational study, we gathered CTG traces under and without the influence of steroids in order to study their effect on the STV using 2 different computational algorithms (STV240 and STV16). RESULTS: A total of 285 CTGs were registered and subsequently analysed with both algorithms. When compared to the STV240 and STV16 without or at least 72 h after the first intramuscular corticosteroid administration, a transient increase of both the STV240 and STV16 was documented in the first 24 h, followed by a transient decrease of both the STV240 and STV16 between 24 h and 72 h after the first intramuscular corticosteroid injection. CONCLUSION: Our results confirmed that betamethasone administration has a transient but significant effect on the STV independently of the algorithm used. These observations stress once again the fact that a decreased STV within the first 72 h after maternal bethametasone administration should not be an indication for early delivery.


Assuntos
Betametasona/farmacologia , Desenvolvimento Fetal/efeitos dos fármacos , Coração Fetal/fisiologia , Movimento Fetal/efeitos dos fármacos , Frequência Cardíaca Fetal/efeitos dos fármacos , Frequência Cardíaca Fetal/fisiologia , Algoritmos , Cardiotocografia , Feminino , Humanos , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Respiração/efeitos dos fármacos
14.
Int J Gynaecol Obstet ; 148(2): 145-156, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31646629

RESUMO

BACKGROUND: Using Doppler to improve detection of intrapartum fetal heart rate (FHR) abnormalities coupled with appropriate, timely intrapartum care in low- and middle-income countries (LMIC) can save lives. OBJECTIVE: To review studies using Doppler to improve detection of intrapartum FHR abnormalities and intrapartum care quality in LMIC health facilities. SEARCH STRATEGY: PubMed, Web of Science, Embase, Global Health, and Scopus were searched from inception to October 2018 by combining terms for Doppler, perinatal outcomes, and FHR monitoring. SELECTION CRITERIA: Selected studies compared Doppler and Pinard stethoscope for detecting/monitoring intrapartum FHR, or described provider and maternal preferences for FHR monitoring in LMIC settings. DATA COLLECTION AND ANALYSIS: Two team members independently screened and collected data. Risk of bias was assessed by Cochrane EPOC criteria. RESULTS: Eleven studies from eight countries were included. Doppler was superior at detecting abnormal intrapartum FHR as compared with Pinard stethoscope, but was not associated with improved perinatal outcomes. Using Doppler on admission helped to accurately measure perinatal deaths occurring after facility admission. CONCLUSION: Studies and program learning are needed to translate improved detection of FHR abnormalities to improved case management in LMICs. Doppler should be used to calculate a facility indicator of intrapartum care quality. PROSPERO registration: CRD42019121924.


Assuntos
Cardiotocografia/métodos , Cardiopatias Congênitas/diagnóstico por imagem , Frequência Cardíaca Fetal/fisiologia , Ultrassonografia Doppler , Países em Desenvolvimento , Feminino , Saúde Global , Humanos , Recém-Nascido , Mortalidade Perinatal , Gravidez , Ensaios Clínicos Controlados Aleatórios como Assunto , Ultrassonografia Pré-Natal
15.
MCN Am J Matern Child Nurs ; 45(2): 82-91, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31714283

RESUMO

Understanding the physiology of fetal oxygenation and various influences on fetal heart rate control supports nurses, midwives, and physicians in interpreting and managing electronic fetal heart rate tracings during labor and birth. Maternal oxygenation, placental circulation and exchange, umbilical blood flow and fetal circulation affect fetal oxygenation, which is reflected in observed fetal heart rate patterns. Fetal heart control is further influenced by the central and autonomic nervous systems, baroreceptors, chemoreceptors, humoral factors, sleep-wake patterns, breathing movements, medications, painful stimuli, sound and vibrations, and temperature. Knowledge of the physiologic basis for fetal heart rate pattern characteristics guides interventions to improve fetal oxygenation when indicated. A review and update on clinical implications of fetal heart rate pattern interpretation based on underlying physiology is presented.


Assuntos
Frequência Cardíaca Fetal/fisiologia , Trabalho de Parto/fisiologia , Adulto , Débito Cardíaco/fisiologia , Cardiotocografia/instrumentação , Cardiotocografia/métodos , Feminino , Humanos , Oxigênio/análise , Oxigênio/sangue , Gravidez
16.
Arch Gynecol Obstet ; 301(2): 405-414, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31781889

RESUMO

PURPOSE: Prenatal stress (PS) during pregnancy affects in utero- and postnatal child brain-development. Key systems affected are the hypothalamic-pituitary-adrenal axis and the autonomic nervous system (ANS). Maternal- and fetal ANS activity can be gauged non-invasively from transabdominal electrocardiogram (taECG). We propose a novel approach to assess couplings between maternal (mHR) and fetal heart rate (fHR) as a new biomarker for PS based on bivariate phase-rectified signal averaging (BPRSA). We hypothesized that PS exerts lasting impact on fHR. METHODS: Prospective case-control study matched for maternal age, parity, and gestational age during the third trimester using the Cohen Perceived Stress Scale (PSS-10) questionnaire with PSS-10 over or equal 19 classified as stress group (SG). Women with PSS-10 < 19 served as control group (CG). Fetal electrocardiograms were recorded by a taECG. Coupling between mHR and fHR was analyzed by BPRSA resulting in fetal stress index (FSI). Maternal hair cortisol, a memory of chronic stress exposure for 2-3 months, was measured at birth. RESULTS: 538/1500 pregnant women returned the questionnaire, 55/538 (10.2%) mother-child pairs formed SG and were matched with 55/449 (12.2%) consecutive patients as CG. Maternal hair cortisol was 86.6 (48.0-169.2) versus 53.0 (34.4-105.9) pg/mg (p = 0.029). At 36 + 5 weeks, FSI was significantly higher in fetuses of stressed mothers when compared to controls [0.43 (0.18-0.85) versus 0.00 (- 0.49-0.18), p < 0.001]. CONCLUSION: Prenatal maternal stress affects the coupling between maternal and fetal heart rate detectable non-invasively a month prior to birth. Lasting effects on neurodevelopment of affected offspring should be studied. TRIAL REGISTRATION: Clinical trial registration: NCT03389178.


Assuntos
Ansiedade/fisiopatologia , Sistema Nervoso Autônomo/fisiologia , Movimento Fetal/fisiologia , Frequência Cardíaca Fetal/fisiologia , Mães/psicologia , Complicações na Gravidez/psicologia , Estresse Psicológico/fisiopatologia , Adulto , Estudos de Casos e Controles , Eletrocardiografia , Feminino , Idade Gestacional , Humanos , Hidrocortisona/análise , Sistema Hipotálamo-Hipofisário , Sistema Hipófise-Suprarrenal , Gravidez , Terceiro Trimestre da Gravidez , Estudos Prospectivos , Estresse Psicológico/complicações
17.
Obesity (Silver Spring) ; 28(1): 114-121, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31858736

RESUMO

OBJECTIVE: Prepregnancy obesity and extensive weight gain can lead to diseases in the offspring later in life. The aim of this study was to evaluate the effect of anthropometric and metabolic factors on the fetal autonomic nervous system (ANS) in uncomplicated pregnancies. METHODS: A total of 184 pregnant women in the second or third trimester were included, and for 104 women, maternal insulin sensitivity (ISI) was determined. Fetal heart rate (HR) and heart rate variability (HRV) were determined by magnetic recording. Associations of maternal prepregnancy BMI, weight gain, and ISI with fetal HR and HRV were evaluated by ANCOVA, partial correlation, and mediation analysis. RESULTS: HR was increased and HRV decreased in fetuses of mothers with overweight or obesity in comparison to normal-weight mothers. Fetal HR was negatively correlated with maternal weight gain. Maternal prepregnancy BMI was positively correlated with fetal high frequency and was negatively correlated with low frequency and low/high frequency ratio. Maternal ISI showed a negative correlation with fetal HR. CONCLUSIONS: The results show that the fetal ANS is sensitive to alterations of prepregnancy BMI, weight changes, and glucose metabolism. These findings highlight the importance of the intrauterine environment on the developing ANS and the possible programming of obesity.


Assuntos
Frequência Cardíaca Fetal/fisiologia , Metabolismo/fisiologia , Obesidade/complicações , Ganho de Peso/fisiologia , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Gravidez , Adulto Jovem
18.
Anim Reprod Sci ; 212: 106255, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31864486

RESUMO

The aim of this study was to compare uterine and umbilical artery blood flow and fetal heart rate (FHR) in small, medium and large body weight (BW) dogs during the second half of pregnancy. Purebred pregnant bitches were assigned to one of the following groups according to their BW: small (S; ≤10 kg), medium (M; 11-25 kg) and large (L; >25-45 kg). Uterine and umbilical Doppler and M-mode ultrasonography was conducted every 10 days from Day 30-60 (Day 0 = first day of gestation). From Day 40, uterine and umbilical artery resistance index (RI) progressively and differentially decreased in the three groups (P < 0.01) being less in L than S bitches (P < 0.01). Litter size but not maternal BW (P > 0.1) affected uterine RI on Days 40 (r = 0.39; P < 0.01) and 50 (r = 0.41; P < 0.01). Conversely, on Day 60, maternal BW (r = 0.61; P < 0.01) had an effect on uterine RI while litter size did not (P > 0.1). Fetal heart rate increased from Day 30-50 and decreased to the time of parturition (P < 0.01) without differences among groups at any time point (P > 0.1). Uterine and umbilical blood flow differentially increased throughout mid- and late-pregnancy in breeds with large and small BW. These differences were affected by litter size on Days 40 and 50, and by maternal BW on Day 60. Conversely, during this same period, FHR did not vary among BW groups. Physiological variations should be considered when gestational ultrasonic examination is interpreted in different BW bitches.


Assuntos
Peso Corporal , Cães/embriologia , Cães/fisiologia , Frequência Cardíaca Fetal/fisiologia , Prenhez , Animais , Velocidade do Fluxo Sanguíneo/veterinária , Feminino , Gravidez , Ultrassonografia Pré-Natal/veterinária , Artérias Umbilicais/fisiologia , Artéria Uterina/fisiologia , Útero/irrigação sanguínea , Resistência Vascular
19.
Arch Gynecol Obstet ; 301(1): 137-142, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31883047

RESUMO

PURPOSE: Phase-rectified signal averaging method (PRSA) represents an analysis method which applied on fetal cardiotocography (CTG) allows the quantification of the speed of fetal heart rate changes. By calculating the average deceleration capacity (ADC) an assessment of the fetal autonomic nervous system (ANS) is possible. The objective of this study was to test its ability to predict perinatal acidosis. METHODS: A case-control study was performed at a University Hospital in Munich. All intrapartum CTG heart rate tracings saved during a 7-year period were considered for analysis. All neonates born with an umbilical arterial blood pH ≤ 7.10 were considered as cases. Controls were defined as healthy fetuses born with a pH ≥ 7.25. The main matching criteria were gestational age at delivery, parity, birth mode, and birth weight percentile. Exclusion criteria were a planned caesarean section, fetal malformations, and multiple pregnancies. ADC and STV were then calculated during the last 60, the last 45, and the last 30 min intervals prior to delivery. RESULTS: Of all stored birth CTG recordings, 227 cases met the inclusion criteria and were studied. ADC was significantly higher in fetuses born with acidemia (4.85 bpm ± 3.0) compared to controls (3.36 bpm ± 2.2). The area under ROC curve was 0.659 (95% CI 0.608-0.710) for ADC and 0.566 (0.512-0.620) for STV (p = 0.013). CONCLUSIONS: This study confirms that the assessment of ADC using PRSA represents a good additional tool for the prediction of acute fetal acidosis during delivery.


Assuntos
Acidose/sangue , Cardiotocografia/métodos , Sangue Fetal/química , Doenças Fetais/diagnóstico , Estudos de Casos e Controles , Feminino , Sangue Fetal/citologia , Doenças Fetais/sangue , Frequência Cardíaca Fetal/fisiologia , Humanos , Masculino , Gravidez
20.
Med Biol Eng Comput ; 58(2): 419-432, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31858419

RESUMO

Early detection of potential hazards in the fetal physiological state during pregnancy and childbirth is very important. Noninvasive fetal electrocardiogram (FECG) can be extracted from the maternal abdominal signal. However, due to the interference of maternal electrocardiogram and other noises, the task of extraction is challenging. This paper introduces a novel single-lead noninvasive fetal electrocardiogram extraction method based on the technique of clustering and PCA. The method is divided into four steps: (1) pre-preprocessing; (2) fetal QRS complexes and maternal QRS complexes detection based on k-means clustering algorithm with the feature of max-min pairs; (3) FQRS correction step is to improve the performance of step two; (4) template subtraction based on PCA is introduced to extract FECG waveform. To verify the performance of the proposed algorithm, two clinical open-access databases are used to check the performance of FQRS detection. As a result, the method proposed shows the average PPV of 95.35%, Se of 96.23%, and F1-measure of 95.78%. Furthermore, the robustness test is carried out on an artificial database which proves that the algorithm has certain robustness in various noise environments. Therefore, this method is feasible and reliable to detect fetal heart rate and extract FECG. Graphical abstract Early detection of potential hazards in the fetal physiological state during pregnancy and childbirth is very important. Noninvasive fetal electrocardiogram (FECG) can be extracted from maternal abdominal signal. However, due to the interference of maternal electrocardiogram and other noises, the task of extraction is challenging. This paper introduces a novel single-lead noninvasive fetal electrocardiogram extraction method based on the technique of clustering and PCA. The method is divided into four steps: (1) pre-preprocessing; (2) fetal QRS complexes and maternal QRS complexes detection based on k-means clustering algorithm with the feature of max-min pairs; (3) FQRS correction step is to improve the performance of step two; (4) template subtraction based on PCA is introduced to extract FECG waveform. To verify the performance of algorithm, two clinical open-access databases are used to check the performance of FQRS detection. As a result, the method proposed shows the average PPV of 95.35%, Se of 96.23%, and F1-measure of 95.78%. Furthermore, the robustness test is carried out on an artificial database which proves that the algorithm has certain robustness in various noise environments. Therefore, this method is feasible and reliable to detect fetal heart rate and extract FECG.


Assuntos
Eletrocardiografia/métodos , Monitorização Fetal/métodos , Frequência Cardíaca Fetal/fisiologia , Processamento de Sinais Assistido por Computador , Algoritmos , Análise por Conglomerados , Feminino , Humanos , Gravidez , Análise de Componente Principal
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