Fetal Heart Rate Decelerations Research Articles

Fetal heart rate tracings associated with eclamptic seizures

Although there is a well-known association between fetal bradycardia and maternal eclampsia, the characteristics of fetal heart rate tracings after an eclamptic seizure have not previously been thoroughly described. Fetal heart rate changes are thought to be related to maternal lactic acidemia caused by vasospasm and uterine hyperactivity leading to placental hypoperfusion and fetal hypoxia. The decision to intervene in the case of an abnormal fetal heart rate tracing after an eclamptic seizure is often difficult; however, maternal resuscitation should be the primary focus. This study aimed to quantify and characterize fetal heart rate changes associated with a maternal eclamptic seizure. Moreover, we sought to document subsequent obstetrical management following these seizures complicated by fetal heart rate decelerations. This was a retrospective study of fetal heart rate tracings associated with eclampsia during a 13-year period at a single institution. Eclampsia was diagnosed following the 2013 Executive Summary of the American College of Obstetricians and Gynecologists criteria. Tracings were independently reviewed and classified by 3 physicians using the National Institute of Child Health and Human Development Criteria. Hospital records were reviewed to ascertain obstetrical management after the eclamptic seizure. A total of 107 women were diagnosed with eclampsia from January 2009 to December 2021. Of these women, 31 experienced 34 intrapartum seizures during which time electronic fetal heart rate monitoring was ongoing. During the 34 seizures, fetal heart rate decelerations were documented in 79% of cases. The mean duration of bradycardia was 5.80±2.98 minutes with a range of 2 to 15 minutes. Fetal heart decelerations occurred, on average, 2.7±1.6 minutes after the onset of the eclamptic seizure. In half of the fetuses with fetal heart rate changes, fetal tachycardia followed, and in 48% of cases, there was minimal variability noted. As a result of the fetal heart rate tracings and clinical findings, 4 women underwent an emergent cesarean delivery, including 2 that were diagnosed with placental abruption. In this cohort, there were 4 cases of abruption. The mean duration from the seizure to delivery was 299±353 minutes. The mean neonatal cord pH was 7.20±0.11 with a mean base excess of-8.6±4.4 mmol/L. There was no perinatal death. After an eclamptic seizure, 79% of fetuses demonstrated prolonged decelerations, and half of the fetuses developed fetal tachycardia after recovery from the episode of bradycardia. Despite these periods of fetal heart rate decelerations associated with eclampsia, prioritization of maternal support and stabilization resulted in a favorable perinatal outcome without immediate operative intervention in more than two-thirds of cases.

Maternal sleep behaviours preceding fetal heart rate events on cardiotocography.

In Australia, a significant proportion of stillbirths remain unexplained. Recent research has highlighted nocturnal maternal behaviours as potentially modifiable contributors. This study determined whether sleep-related behaviours including sleep position and sleep-disordered breathing adversely affect fetuses overnight, in both uncomplicated pregnancies and those at increased risk due to hypertensive disorders or fetal growth restriction (FGR). All participants underwent polysomnography with time-synchronized fetal heart rate (FHR) monitoring (cardiotocography - CTG) in late pregnancy. CTGs were analysed for abnormal FHR events, including decelerations and reduced variability, by two blinded observers and exported into the sleep study to temporally align FHR events with sleep behaviours. For each FHR event, 10 control epochs with normal FHR were randomly selected for the same participant. Conditional logistic regression assessed the relationships between FHR events and sleep behaviours. From 116 participants, 52 had a total of 129 FHR events overnight; namely prolonged decelerations and prolonged periods of reduced variability. Significantly more FHR events were observed in women with FGR and/or a hypertensive disorder compared with uncomplicated pregnancies (P=0.006). FHR events were twice as likely to be preceded by a change in body position within the previous 5min, compared with control epochs (P=0.007), particularly in hypertensive pregnancies both with and without FGR. Overall, FHR events were not temporally related to supine body position, respiratory events or snoring. Our results indicate that most fetuses tolerate sleep-related stressors, but further research is needed to identify the interplay of maternal and fetal conditions putting the fetus at risk overnight. KEY POINTS: Maternal sleep behaviours including supine position and sleep-disordered breathing are potential contributors to stillbirth but much of this work is based on self-reported data. Using time-synchronized polysomnography and cardiotocography, we found that nocturnal fetal heart rate decelerations were more likely to be preceded by a change in body position compared with epochs containing normal fetal heart rate, particularly in hypertensive pregnancies with or without fetal growth restriction. There was no temporal relationship between maternal sleeping position, snoring or apnoeic events and an abnormal fetal heart rate overnight. We conclude that most fetuses can tolerate sleep-related stressors with no evidence of fetal heart rate changes indicating compromised wellbeing. Further work needs to identify how sleep behaviours contribute to stillbirth risk and how these intersect with underlying maternal and fetal conditions.

Physiological control of fetal heart rate variability during labour: implications and controversies.

The interpretation of fetal heart rate (FHR) patterns is the only available method to continuously monitor fetal well-being during labour. One of the most important yet contentious aspects of the FHR pattern is changes in FHR variability (FHRV). Some clinical studies suggest that loss of FHRV during labour is a sign of fetal compromise so this is reflected in practice guidelines. Surprisingly, there is little systematic evidence to support this observation. In this review we methodically dissect the potential pathways controlling FHRV during labour-like hypoxaemia. Before labour, FHRV is controlled by the combined activity of the parasympathetic and sympathetic nervous systems, in part regulated by a complex interplay between fetal sleep state and behaviour. By contrast, preclinical studies using multiple autonomic blockades have now shown that sympathetic neural control of FHRV was potently suppressed between periods of labour-like hypoxaemia, and thus, that the parasympathetic system is the sole neural regulator of FHRV once FHR decelerations are present during labour. We further discuss the pattern of changes in FHRV during progressive fetal compromise and highlight potential biochemical, behavioural and clinical factors that may regulate parasympathetic-mediated FHRV during labour. Further studies are needed to investigate the regulators of parasympathetic activity to better understand the dynamic changes in FHRV and their true utility during labour.

Preterm prelabor rupture of membranes prior to 33 0/7 weeks: when should rescue corticosteroids be given?

Objective To determine an optimal timing strategy for rescue corticosteroids in gravidas with preterm prelabor rupture of membranes (PPROM) prior to 33 0/7 weeks. Methods This was a retrospective cohort analysis of 109 gravidas with a singleton gestation and PPROM between 23 0/7 and 32 6/7 weeks who delivered at a single inner city tertiary care center. The time of the actual first dose of corticosteroids was chosen as Time 0. The date and time of labor onset, chorioamnionitis, heavy bleeding, cord prolapse, or fetal heart rate decelerations warranting delivery were recorded, as well as the date and time of delivery. We then compared hypothetical timing strategies for administration of the rescue course of corticosteroids at either 1, 2, or 3 weeks after the first course if still undelivered, compared to a strategy of withholding the rescue course until the recognition of spontaneous labor or the need for delivery. For each strategy, we calculated the percentage of gravidas who would have delivered within the optimal window after rescue course corticosteroids, defined as delivery at 24 h to 7 days from the first rescue dose. Results The median time from PPROM to delivery among the 109 gravidas was 8.9 days (interquartile range 4.4–17.9 days). Forty-eight (44%) gravidas delivered within the first week after initial corticosteroid administration, leaving 61 (56%) eligible for a rescue dose. In our hypothetical models, the strategy of giving rescue corticosteroids at either 1, 2, or 3 weeks from the first course would have resulted in 34.4%, 23.0%, and 19.7% of infants being born at 24 h to 7 days after the first rescue dose, respectively. These differences among the three groups or between any two groups were not statistically significant. However, all fixed interval strategies were statistically superior to the strategy of waiting for spontaneous labor or the need for delivery, in which only 4.9% would have delivered within the optimal window. Conclusion In gravidas with PPROM prior to 33 0/7 weeks, giving rescue corticosteroids at a fixed interval of either 1, 2, or 3 weeks after the first course would result in a greater percentage of infants being born within the optimal 24 h to 7 day window compared to administering the rescue course at the onset of labor, infection, bleeding, or abnormal fetal heart rate tracing.

Single sporadic deceleration during reactive nonstress test – clinical significance and risk for cesarean delivery

The nonstress test (NST) is a widely applied technique for antepartum fetal assessment despite a high false-positive rate. The evidence regarding the clinical significance of a single sporadic variable deceleration (SSD) in fetal heart rate (FHR) during reactive NST is scarce, and therefore, the optimal management of SSD in a term pregnancy without other signs of fetal compromise has not been established. Thus, we aim to evaluate whether SSD during a reactive NST at term is associated with a higher risk for FHR decelerations during labor and need for intervention.

Differences in the Asymmetry of Beat-to-Beat Fetal Heart Rate Accelerations and Decelerations at Preterm and Term Active Labor.

The fetal autonomic nervous system responds to uterine contractions during active labor as identified by changes in the accelerations and decelerations of fetal heart rate (FHR). Thus, this exploratory study aimed to characterize the asymmetry differences of beat-to-beat FHR accelerations and decelerations in preterm and term fetuses during active labor. In an observational study, we analyzed 10 min of fetal R-R series collected from women during active preterm labor (32–36 weeks of pregnancy, n = 17) and active term labor (38–40 weeks of pregnancy, n = 27). These data were used to calculate the Deceleration Reserve (DR), which is a novel parameter that quantifies the asymmetry of the average acceleration and deceleration capacity of the heart. In addition, relevant multiscale asymmetric indices of FHR were also computed. Lower values of DR, calculated with the input parameters of T = 50 and s = 10, were associated with labor occurring at the preterm condition (p = 0.0131). Multiscale asymmetry indices also confirmed significant (p < 0.05) differences in the asymmetry of FHR. Fetuses during moderate premature labor may experience more decaying R-R trends and a lower magnitude of decelerations compared to term fetuses. These differences of FHR dynamics might be related to the immaturity of the fetal cardiac autonomic nervous system as identified by this system response to the intense uterine activity at active labor.

Relationship Between Deceleration Morphology and Phase Rectified Signal Averaging-Based Parameters During Labor.

During labor, uterine contractions trigger the response of the autonomic nervous system (ANS) of the fetus, producing sawtooth-like decelerations in the fetal heart rate (FHR) series. Under chronic hypoxia, ANS is known to regulate FHR differently with respect to healthy fetuses. In this study, we hypothesized that such different ANS regulation might also lead to a change in the FHR deceleration morphology. The hypothesis was tested in an animal model comprising nine normoxic and five chronically hypoxic fetuses that underwent a protocol of umbilical cord occlusions (UCOs). Deceleration morphologies in the fetal inter-beat time interval (FRR) series were modeled using a trapezoid with four parameters, i.e., baseline b, deceleration depth a, UCO response time τu and recovery time τr. Comparing normoxic and hypoxic sheep, we found a clear difference for τu (24.8±9.4 vs. 39.8±9.7 s; p < 0.05), a (268.1±109.5 vs. 373.0±46.0 ms; p < 0.1) and Δτ = τu − τr (13.2±6.9 vs. 23.9±7.5 s; p < 0.05). Therefore, the animal model supported the hypothesis that hypoxic fetuses have a longer response time τu and larger asymmetry Δτ as a response to UCOs. Assessing these morphological parameters during labor is challenging due to non-stationarity, phase desynchronization and noise. For this reason, in the second part of the study, we quantified whether acceleration capacity (AC), deceleration capacity (DC), and deceleration reserve (DR), computed through Phase-Rectified Signal Averaging (PRSA, known to be robust to noise), were correlated with the morphological parameters. DC, AC and DR were correlated with τu, τr and Δτ for a wide range of the PRSA parameter T (Pearson's correlation ρ > 0.8, p < 0.05). In conclusion, deceleration morphologies have been found to differ between normoxic and hypoxic sheep fetuses during UCOs. The same difference can be assessed through PRSA based parameters, further motivating future investigations on the translational potential of this methodology on human data.

Roles of parasympathetic outflow and sympathetic outflow in the cardiovascular response to brief umbilical cord occlusion in fetal sheep.

Fetal heart rate (FHR) deceleration is the most common change seen during labor. The role of the autonomic nervous system in regulating the fetal cardiovascular response during multiple uterine contractions has been well-established. However, the mechanism underlying the hemodynamic response remains unclear and the specific reflex that mediates the cardiovascular modifications is still controversial. This study aimed to determine the role of the sympathetic and parasympathetic systems on fetal hemodynamics in complete cord occlusion. Chronically instrumented fetal sheep were randomized to receive an intravenous injection of atropine 2.5 mg (n = 8), propranolol 5 mg (n = 7), atropine and propranolol (n = 7), or a control protocol (n = 9), followed by three episodes of 1-minute umbilical cord occlusion repeated every 5 minutes. Cord compression induces a rapid decrease in the FHR and a rapid increase in MAP. The decrease in FHR is caused by an increase in parasympathetic activity, (atropine and atropine-propranolol abolish the FHR response to the occlusion). The change in FHR during occlusion was not modified by propranolol injection, showing no effect of sympathetic tone. The increase in MAP during occlusion was similar in the four protocols. After releasing occlusion, the FHR was still lower than that at baseline due to a sustained parasympathetic tone. Suppression of the parasympathetic output to the cardiovascular system unmasks an increase in the FHR above baseline values. The lower FHR with the propranolol protocol further supports an increase in myocardial β-adrenoceptor stimulation after cord release. The increase in MAP after cord release was similar in the four protocols, except after the early stage of interocclusion period in atropine protocol. Four minutes after cord release, the FHR returned to baseline irrespective of the drugs that were infused, thereby showing recovery of ANS control. Blood gases (pH, PaCO2, PaO2) and plasma lactate concentrations was similar between the four protocols at the end of three applications of UCO. Complete cord compression-induced deceleration is likely due to acute activation of parasympathetic output. β-adrenoceptor activity is involved in the increase in FHR after cord release. Understanding the reflexes involved in FHR deceleration may help us understand the mechanisms underlying fetal autonomic adaptation during cord occlusion.

Intrapartal cardiotocographic patterns and hypoxia-related perinatal outcomes in pregnancies complicated by gestational diabetes mellitus

AimsIn previous reports, cardiotocographic (CTG) fetal heart rate (FHR) monitoring has shown only limited benefits in decreasing adverse perinatal outcomes in pregnancies complicated by gestational diabetes mellitus (GDM). The aim of the present study was to evaluate whether an association exists between the recently reported ZigZag pattern (FHR baseline amplitude changes of > 25 bpm with a duration of 2–30 min) and asphyxia-related neonatal outcomes in GDM pregnancies.MethodsIntrapartal CTGs were recorded in a one-year cohort of 5150 singleton childbirths. The following CTG changes were evaluated: ZigZag pattern, saltatory pattern, late decelerations, episodes of tachycardia and bradycardia, reduced variability, and uterine tachysystole. The cohort was divided into three groups: women with GDM, women with normal oral glucose tolerance test (OGTT), and women with no OGTT performed. Umbilical artery (UA) blood gases, Apgar scores, neonatal respiratory distress, and neonatal encephalopathy were used as outcome variables.ResultsGDM was diagnosed in 624 (12.1%), OGTT was normal in 4115 (79.9%), and OGTT was not performed in 411 (8.0%) women. Hypoxia-related ZigZag patterns (OR 1.94, 95% CI 1.64–2.34) and late decelerations (OR 1.65, 95% CI 1.27–2.13) of FHR, as well as a greater risk of fetal asphyxia (UA pH < 7.10 and/or UA BE < -12.0 meq/L and/or Apgar scores < 7 at 5-min) (OR 6.64, 95% CI 1.84–12.03) were observed in those with GDM compared with those without GDM.ConclusionsGDM is associated with intrapartal ZigZag pattern and late decelerations, cord blood acidemia and low 5-min Apgar scores at birth indicating increased occurrence of fetal hypoxia in GDM pregnancies.

Fetal Cardiovascular Decompensation During Labor Predicted From the Individual Heart Rate Tracing: A Machine Learning Approach in Near-Term Fetal Sheep Model.

Background: When exposed to repetitive umbilical cord occlusions (UCO) with worsening acidemia, fetuses eventually develop cardiovascular decompensation manifesting as pathological hypotensive arterial blood pressure (ABP) responses to fetal heart rate (FHR) decelerations. Failure to maintain cardiac output during labor is a key event leading up to brain injury. We reported that the timing of the event when a fetus begins to exhibit this cardiovascular phenotype is highly individual and was impossible to predict.Objective: We hypothesized that this phenotype would be reflected in the individual behavior of heart rate variability (HRV) as measured by root mean square of successive differences of R-R intervals (RMSSD), a measure of vagal modulation of HRV, which is known to increase with worsening acidemia. This is clinically relevant because HRV can be computed in real-time intrapartum. Consequently, we aimed to predict the individual timing of the event when a hypotensive ABP pattern would emerge in a fetus from a series of continuous RMSSD data.Study Design: Fourteen near-term fetal sheep were chronically instrumented with vascular catheters to record fetal arterial blood pressure, umbilical cord occluder to mimic uterine contractions occurring during human labor and ECG electrodes to compute the ECG-derived HRV measure RMSSD. All animals were studied over a ~6 h period. After a 1–2 h baseline control period, the animals underwent mild, moderate, and severe series of repetitive UCO. We applied the recently developed machine learning algorithm to detect physiologically meaningful changes in RMSSD dynamics with worsening acidemia and hypotensive responses to FHR decelerations. To mimic clinical scenarios using an ultrasound-based 4 Hz FHR sampling rate, we recomputed RMSSD from FHR sampled at 4 Hz and compared the performance of our algorithm under both conditions (1,000 Hz vs. 4 Hz).Results: The RMSSD values were highly non-stationary, with four different regimes and three regime changes, corresponding to a baseline period followed by mild, moderate, and severe UCO series. Each time series was characterized by seemingly randomly occurring (in terms of timing of the individual onset) increase in RMSSD values at different time points during the moderate UCO series and at the start of the severe UCO series. This event manifested as an increasing trend in RMSSD values, which counter-intuitively emerged as a period of relative stationarity for the time series. Our algorithm identified these change points as the individual time points of cardiovascular decompensation with 92% sensitivity, 86% accuracy and 92% precision which corresponded to 14 ± 21 min before the visual identification. In the 4 Hz RMSSD time series, the algorithm detected the event with 3 times earlier detection times than at 1,000 Hz, i.e., producing false positive alarms with 50% sensitivity, 21% accuracy, and 27% precision. We identified the overestimation of baseline FHR variability by RMSSD at a 4 Hz sampling rate to be the cause of this phenomenon.Conclusions: The key finding is demonstration of FHR monitoring to detect fetal cardiovascular decompensation during labor. This validates the hypothesis that our HRV-based algorithm identifies individual time points of ABP responses to UCO with worsening acidemia by extracting change point information from the physiologically related fluctuations in the RMSSD signal. This performance depends on the acquisition accuracy of beat to beat fluctuations achieved in trans-abdominal ECG devices and fails at the sampling rate used clinically in ultrasound-based systems. This has implications for implementing such an approach in clinical practice.

Fetal Heart Rate Decelerations in Women with Sleep-Disordered Breathing.

Emerging literature has shown that women with sleep-disordered breathing (SDB) have increased risk for gestational hypertension/preeclampsia and gestational diabetes. Case reports suggest an association between maternal apnea and fetal heart rate deceleration but data are lacking on how maternal sleep impacts fetal health. Since decelerations may be associated with adverse outcomes, we sought to determine whether fetal heart rate decelerations were associated with SDB. A cohort study of third trimester pregnant women with a singleton fetus was conducted. Participants underwent a home sleep test with continuous portable electronic fetal monitoring. SDB was defined as a respiratory disturbance index (RDI)≥10 events/hour. The temporality between a respiratory event and fetal heart rate decelerations was determined to be present if a deceleration occurred < 30 s after a respiratory event. Forty women were included with mean (±SD) age, BMI, and gestational age of 32.0±5.5 years, 37.1±8.0 kg/m2, and 34.6±2.4 weeks respectively. Overall, n=23 (57.5%) women had SDB. Thirty-seven late decelerations were observed in 18 women; of these, 84% were temporally associated with a respiratory event. Nine of the 18 women (50%) had SDB. Ten prolonged decelerations were observed in 6 women of which nine (90%) were temporally associated with a respiratory event. Five of the six women (83%) had an RDI≥10. These initial data suggest that, in this population, the majority of both late and prolonged fetal heart rate decelerations occur with a maternal respiratory event. Since respiratory events are characteristic of maternal SDB, this raises the possibility that SDB may influence fetal well-being.

Cardiotocograph (CTG) changes and maternal and neonatal outcomes in chorioamnionitis and/or funisitis confirmed on histopathology

ObjectiveTo assess the cardiotocographic changes and maternal and neonatal outcomes in cases of chorioamnionitis and or funisitis confirmed on histopathology. Study DesignA retrospective analysis of histopathology reports confirming chorioamnionitis and/or funisitis was carried out from 2014 to 2020 in a single centre. The preterm births (<37 weeks) were excluded. The maternal records were reviewed to determine the maternal and neonatal outcomes such as the mode of delivery, intrapartum and postpartum complications, umbilical cord arterial pH, and admission to the special care baby unit (SCBU). The CTG features were analysed on admission and during the intrapartum period. The study was approved by the Audit and Clinical Effectiveness department within the centre. ResultsOut of the 57 cases of histologically confirmed chorioamnionitis and/or funisitis, 42 women (73.7 %) had intrapartum pyrexia and none of the mothers had an increased temperature at the point of fetal tachycardia (persistent increase in baseline fetal heart rate (FHR) by >10 % compared to the original baseline FHR). 43 (75.4 %) CTGs showed evidence of uterine tachysystole or hyperstimulation. 15 (26.3 %) cases had meconium stained amniotic fluid (MSAF). 54 (94.7 %) women had a caesarean section, and their babies were admitted to special care baby unit after delivery. 54 (94.7 %) babies had an umbilical artery of more than 7.1. 47 (87 %) of the women were readmitted with wound infection.All CTG traces showed a > 10 % increase in the baseline FHR and variable decelerations with overshoot were noted in cases where funisitis was confirmed in 25 cases (92.6 %). Loss of cycling was noted in 54 CTGs (94.7 %) and a sinusoidal pattern was identified in 27 (47.3 %). ConclusionRising (>10 %) baseline during labour along with loss of cycling with or without features of tachysystole or hyperstimulation should be considered in labour as features of ongoing chorioamnionitis. Chorioamnionitis confirmed on histopathology is associated with an increase in caesarean section rate due to fetal heart rate changes, increased risk of wound infection in mothers, and increased admission of the babies to SCBU.

A Case of Emergency Cesarean Section with Pseudopregnancy

Background: Pseudopregnancy is a physical state whereby all the signs and symptoms of pregnancy are exhibited with the exception of the presence of a fetus. The detection of a pseudopregnancy is significant; however, as it may be associated with all pregnancy symptoms, it is important to differentiate between the two. Case report: We report a case of pseudopregnancy leading to an emergency cesarean section. A 28-year-old woman claiming a 7-month pregnancy was referred to a rural health center by her in-laws complaining of vaginal bleeding. The woman was referred to an urban hospital by emergency medical services with a diagnosis of placenta previa. In the hospital, she underwent an emergency cesarean section due to a severe deceleration of fetal heart rate (FHR), prior to assessing by an ultrasound. No fetus or signs of uterine or abdominal pregnancy was observed. Wrong auscultation of the maternal heart rate instead of FHR seemed to be the main error. Conclusion: It is required to pay more attention to the methods of differentiation of FHR from maternal heart rate. This report highlighted the significance of early detection of pseudopregnancy.

Continuous Fetal Monitoring During Electroconvulsive Therapy: A Prospective Observation Study.

ObjectiveThe use of electroconvulsive therapy in pregnancy has been limited by concerns about its effects on fetal well-being, despite limited evidence that suggests it is safe and effective. No studies have utilized continuous fetal heart rate monitoring during electroconvulsive therapy sessions. We aimed to describe the fetal heart rate patterns of patients undergoing electroconvulsive therapy.DesignThis study is a prospective case series of pregnant patients undergoing electroconvulsive therapy with continuous fetal heart rate monitoring.SettingUniversity-based hospital.PopulationPregnant patients with a psychiatric indication for electroconvulsive therapy.MethodsPatients underwent fetal heart rate monitoring immediately prior, during and immediately after ECT therapy.Main Outcome MeasuresCharacterization of the fetal heart rate tracing.ResultsFive subjects underwent 44 electroconvulsive therapy sessions. Continuous fetal monitoring was performed on 34 of the sessions. Transient fetal heart rate decelerations occurred in 4 sessions, all self-resolved and none required intervention.ConclusionThis case series is the first to report the results of continuous FHR monitoring during electroconvulsive therapy. The most common finding was a transient, self-resolving bradycardia that was not associated with adverse perinatal outcomes. This supports the opinion that electroconvulsive therapy is a safe treatment option in pregnancy in women with severe mental disease.

Lower, Variable Intrathecal Opioid Doses, and the Incidence of Prolonged Fetal Heart Rate Decelerations After Combined Spinal Epidural Analgesia for Labor: A Quality Improvement Analysis.

BackgroundCombined spinal-epidurals with low-dose intrathecal opioids and local anesthetics are commonly used to initiate labor analgesia due to the fast onset of analgesia and good patient satisfaction. Intrathecal fentanyl has been associated with fetal bradycardia, and the rate may be higher at doses of 25 mcg and above. As such, our institution limits intrathecal fentanyl doses to less than 15 mcg for labor. Prompted by a few incidents of prolonged fetal bradycardia at even these low doses, we sought to audit the side effects associated with varying low doses of intrathecal fentanyl.MethodsAfter IRB approval, a retrospective review was performed on 555 labor records from May–December, 2016. All the patients received combined spinal epidurals for labor analgesia. Intrathecal medication consisted of 1 mL of 0.25% bupivacaine, and varying fentanyl doses: 2.5, 5, 10, and 15 mcg. The incidences of prolonged fetal heart rate decelerations, emergent cesarean delivery, magnitude of pain reduction, pruritus requiring treatment, and hypotension were compared.ResultsDemographic variables were equivalent between the groups. There were no differences in the rates of prolonged fetal decelerations (in order of increasing fentanyl dose: 4.4%, 2.3%, 7.6%, 3.0%, p-value = 0.11), emergent cesarean delivery, magnitude of pain reduction, pruritus, or maternal hypotension.ConclusionsIn conclusion, the rates of prolonged fetal heart rate decelerations after combined spinal epidural with intrathecal bupivacaine and fentanyl does not differ for fentanyl doses of 15 mcg and below.

Diagnosis of uterine torsion during cesarean section

Partial rotation of the uterus up to 45 degrees is a common physiological finding during pregnancy whereas uterine torsion is pathologic and defined as rotation greater than 45 degrees. Torsion of up to 720 degrees has been reported; with most cases occurring between 90 degrees and 180 degrees. While uterine torsion in pregnancy requires emergent intervention, the incidence is unknown. Most cases of uterine torsion are diagnosed intra-operatively at emergent cesarean section following non-specific clinical presentation, such as fetal heart rate decelerations or bradycardia, severe abdominal pain, hypotension, or vaginal bleeding. In this case series, we report on two cases of one woman with gravid uterine levorotation of 180 degrees and another with gravid uterine dextrorotation of 180 degrees.

A randomized controlled trial studying the effect of maternal hyperoxygenation on fetal heart rate in suspected fetal distress

Objective: To investigate the effect of maternal hyperoxygenation on fetal heart rate (FHR) when applied for suspected fetal distress during the second stage of term labor. Approach: A single-center randomized controlled trial was conducted in a tertiary care hospital in The Netherlands. Participants were included during the second stage of labor in case of an intermediary or abnormal FHR pattern. Patients were randomized to receive either 100% oxygen at 10 l/min until delivery, or conventional care without additional oxygen. The primary outcome was the change in FHR pattern before and after the onset of the study, measured as the change in depth and duration of FHR decelerations. Secondary outcome measures were features based on phase-rectified signal averaging (PRSA), baseline assignability, and deceleration characteristics of the FHR pattern. Main results: Between March 2016 and April 2018, 117 women were included. The FHR pattern could be analyzed for 71 participants, the other 46 women delivered before the end of the post time-frame. A 2.3% reduction in depth and duration of FHR decelerations was found after maternal hyperoxygenation, compared to a 10% increase in the control group (p = 0.24). Maternal hyperoxygenation had a significantly positive effect on PRSA metrics, with a decrease in PRSA-acceleration capacity (p = 0.03) and PRSA-deceleration capacity (p = 0.02) in the intervention group compared to the control group. Significance: The difference in depth and duration of decelerations after the start of the study was not significantly different between both study groups. A statistically significant positive effect on PRSA-deceleration capacity and PRSA-acceleration capacity was found after maternal hyperoxygenation, which might be associated with a positive effect on neonatal outcome.

Asymptomatic complete heart block in labor: A case report of none response to atropine therapy

Introduction: A complete heart block is a cardiac electrical conduction disorder with a very rare occurrence in pregnancy, which may be asymptomatic. There are no specific guidelines for the management of asymptomatic complete heart block in labor, vaginal delivery, and cesarean with only a few reports of cesarean management of patients with complete heart block. Case report: A 30-year-old woman, Gravida 4, abortion 3, gestational age of 41 weeks without any specific problems, was referred to our maternity hospital. The pulse rate and blood pressure were 68 and 60/110, respectively. Labor was induced with oxytocin and, after three hours, was discontinued due to late decelerations of fetal heart rate. Electrocardiography confirmed a maternal pulse rate of 42. Cardiac consultation led to the diagnosis of a complete heart block. Due to the frequent late decelerations of fetal heart rate and no response to atropine therapy, the patient was a candidate for a cesarean. Before cesarean, the pacemaker was installed. Cesarean was performed with general anesthesia, and the infant was delivered in good condition. In Postpartum, the pacemaker was removed (PR=55, BP=125/80), and the mother was discharged the next day. Due to the lack of specific guidelines, fetal indication for an emergency cesarean, mother poor obstetrics history, and none response to atropine therapy, we chose to incorporate pacemakers and remove it after cesarean safely. Conclusion: Vital signs assessment during pregnancy and childbirth is recommended to detect cases of complete heart block and provide optimal care.

Umbilical and Middle Cerebral Artery Doppler Measurements in Fetuses With Congenital Heart Block

In fetal congenital complete heart block, the slow fetal heart rate prolongs the diastolic phase of the cardiac cycle, which may affect Doppler measurements that are typically used to quantify placental function. We here describe the umbilical artery (UA) and middle cerebral artery (MCA) Dopplers in a cohort of fetuses with heart block, hypothesizing that values will be increased but nevertheless remain associated with placental function and fetal outcome. We retrospectively reviewed Doppler measurements of the UA and MCA pulsatility index (PI) and resistance index in fetuses with complete heart block. The cerebroplacental ratio (CPR) was calculated as a marker of central redistribution. Measurements were transformed to Z scores and compared between fetuses born with a normal weight (appropriate for gestational age [AGA]) to those with fetal growth restriction (FGR) and correlated with a composite adverse outcome consisting of FGR, fetal death, or preterm birth prior to 34weeks' gestation. Fifty-four fetuses were included. There were 36 (67%) live births, 8 (22%) stillbirths, and 10 (19%) pregnancy terminations. Of those born alive, 14 (39%) had FGR. The UA PI decreased with gestational age and was higher in FGR compared with AGA fetuses (P<.001). Twenty-three percent of AGA fetuses developed absent end-diastolic flow in the UA. The MCA PI did not change with gestation and did not differ between AGA and FGR fetuses. The CPR was lower in FGR than in AGA fetuses (-2.43±0.85 vs -1.44±1.04, P=.006). The UA PI and resistance index were strongly correlated with the composite adverse outcome (P<.001). The UA and MCA PI are significantly elevated in fetuses with complete heart block. The UA Doppler indices and CPR nevertheless still reflect placental function. Longitudinal measurements may be useful in monitoring well-being in fetuses with heart block.

Cerebral Palsy is 25 or More of Hypoxia Index and No Cerebral Palsy is 24 or Less of Index in Fetal Monitoring

Fetal outcome was ominous if fetal heart rate (FHR) was late deceleration (LD) in the past, while 3 connected typical LDs were normal, and repeated LDs for 50 min were heavy fetal brain damage. Also, LD is defined as LD when it is repeated for 15 minutes. As the fetus is damaged by repeated hypoxic decelerations followed by cerebral palsy, but not by its late appearing in LD, novel fetal hypoxia index (HI) is the sum of all deceleration durations (min) divided by the lowest FHR (bpm) and multiplied by 100 in fetal monitoring. The hypoxia index was 25 or more in all of 6 cerebral palsy cases, while it was 24 or less in all 16 cases of no cerebral palsy. As error probability is almost zero in the chi2 test of hypoxia index, no cerebral palsy is decided when the hypoxia index is 24 or less, while it is cerebral palsy, if hypoxia index is 25 or more. The hypoxia index is adopted to all FHR decelerations and bradycardia, as hypoxia index does not evaluate the late appearing of deceleration, instead of past subjective deceleration pattern diagnosis in fetal monitoring.