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OBJECTIVE: To compare interpretability of two intrapartum abdominal fetal heart rate monitoring strategies. We hypothesized that an external fetal electrocardiography monitoring system, a newer technology using wireless abdominal pads, would generate more interpretable fetal heart rate data compared to standard external Doppler fetal heart rate monitoring (standard external monitoring). STUDY DESIGN: We conducted a randomized controlled trial at four Utah hospitals. Patients were enrolled at labor admission and randomized in blocks based on body mass index to fetal electrocardiography or standard external monitoring. Two reviewers, blinded to study allocation, reviewed each fetal heart rate tracing. The primary outcome was the percentage of interpretable minutes of fetal heart rate tracing. An interpretable minute was defined as >25% fetal heart rate data present and no more than 25% continuous missing fetal heart rate data or artifact present. Secondary outcomes included the percentage of interpretable minutes of fetal heart rate tracing obtained while on study device only, the number of device adjustments required intrapartum, clinical outcomes, and patient/provider device satisfaction. We determined that 100 patients per arm (200 total) would be needed to detect a 5% difference in interpretability with 95% power. RESULTS: 218 women were randomized, 108 to fetal electrocardiography and 110 to standard external monitoring. Device set up failure occurred more often in the fetal electrocardiography group (7.5% (8/107) versus 0% (0/109) for standard external monitoring). There were no differences in the percent of interpretable tracing between the two groups. However, fetal electrocardiography produced more interpretable fetal heart rate tracing in subjects with body mass index ≥30. When considering the percentage of interpretable minutes of fetal heart rate tracing while on study device only, fetal electrocardiography outperformed standard external monitoring for all subjects, regardless of maternal body mass index. Maternal demographics and clinical outcomes were similar between arms. In the fetal electrocardiography group, more device changes occurred compared to standard external monitoring (51% vs. 39%), but there were fewer nursing device adjustments (2.9 vs. 6.2 mean adjustments intrapartum, p

Intrapartum fetal heart rate monitoring was introduced with the goal to reduce fetal hypoxia and deaths. However, continuous fetal heart rate monitoring has been shown to have a high sensitivity but also a high false-positive rate. To improve specificity, adjunctive technologies have been developed to identify fetuses at risk for intrapartum asphyxia. Intensive research on the value of ST-segment analysis of the fetal electrocardiogram as an adjunct to standard electronic fetal monitoring in lowering the rates of fetal metabolic acidosis and operative deliveries has been ongoing. The conflicting results in randomized and observational studies may partly be due to differences in study design.This study aims to determine the significance of the learning process for the introduction of ST analysis into clinical practice and its impact on initial and subsequent obstetric outcomes.This was a prospective observational study with the primary objective to evaluate the importance of the learning period on the rates of metabolic acidosis and operative deliveries after the implementation of ST analysis. The study was conducted at the Turku University Hospital, Turku, Finland, with 3400-4200 annual deliveries. The whole study population consisted of all 42,146 deliveries during the study period 2001 through 2011. The ST analysis usage rate was 18%. The data were collected prospectively from labors monitored with ST analysis as an adjunct to conventional intrapartum fetal heart rate monitoring. Primary endpoints were the rates of metabolic acidosis (cord artery pH7.05 and an extracellular fluid compartment base deficit12.0 mmol/L), fetal scalp blood sampling, and operative deliveries. Comparisons of these outcomes were made between the initiation period (the first 2 years) and the subsequent usage period (the next 9 years).In the whole study population the prevalence of cord pH7.05 decreased from 1.5-0.81% (relative risk, 0.54; 95% confidence interval, 0.43-0.67), the rate of cesarean deliveries from 17.2-14.1% (relative risk, 0.82; 95% confidence interval, 0.89-0.97), and the rate of fetal scalp blood sampling from 1.75-0.82% (relative risk, 0.47; 95% confidence interval, 0.38-0.58) when the 2 study periods were compared. In the ST analysis group, the frequency of cord metabolic acidosis rate was reduced from 1.0-0.25% (relative risk, 0.33; 95% confidence interval, 0.15-0.72).We provide evidence that the results improve over time and there is a learning curve in the introduction of the ST analysis method. This was demonstrated by the lower rates of metabolic acidosis and operative deliveries after the initial implementation period.

The Perinatal Quality Foundation has created an examination containing both knowledge-based and judgment questions relating to the interpretation of electronic fetal heart rate monitoring for credentialing all medical and nursing personnel working on a labor and delivery floor. A description of the examination and the rationale for its use throughout the United States is presented.

In 1999, a highly publicized report from the Institute of Medicine identified major deficiencies in the United States health care system, which fueled the rapid growth of the modern patient safety movement. One of the greatest risks to patient safety in obstetrics is poor communication of electronic fetal heart rate monitoring findings. Standardization and elimination of unnecessary complexity are 2 of the cornerstones of improved patient safety. This article describes a standardized, simplified approach to the definition, interpretation, and management of electronic fetal heart rate monitoring that is evidence-based and reflects consensus in the literature.

Background Despite intensive efforts directed at initial training in fetal heart rate interpretation, continuing medical education, board certification/recertification, team training, and the development of specific protocols for the management of abnormal fetal heart rate patterns, the goals of consistently preventing hypoxia-induced fetal metabolic acidemia and neurologic injury remain elusive. Objective The purpose of this study was to validate a recently published algorithm for the management of category II fetal heart rate tracings, to examine reasons for the birth of infants with significant metabolic acidemia despite the use of electronic fetal heart rate monitoring, and to examine critically the limits of electronic fetal heart rate monitoring in the prevention of neonatal metabolic acidemia. Study Design The potential performance of electronic fetal heart rate monitoring under ideal circumstances was evaluated in an outcomes-blinded examination fetal heart rate tracing of infants with metabolic acidemia at birth (base deficit, >12) and matched control infants (base deficit, Results During the study period, 120 infants were identified with an arterial cord blood base deficit of >12 mM/L. Matched control infants were not demographically different from subjects. In actual practice, operative intervention on the basis of an abnormal fetal heart rate tracings occurred in 36 of 120 fetuses (30.0%) with metabolic acidemia. Based on expert, algorithm-assisted reviews, 55 of 120 patients with acidemia (45.8%) were judged to need operative intervention for abnormal fetal heart rate tracings. This difference was significant ( P =.016). In infants who were born with a base deficit of >12 mM/L in which blinded, algorithm-assisted expert review indicated the need for operative delivery, the decision for delivery would have been made an average of 131 minutes before the actual delivery. The rate of expert intervention for fetal heart rate concerns in the nonacidemic control group (22/120; 18.3%) was similar to the actual intervention rate (23/120; 19.2%; P =1.0) Expert review did not mandate earlier delivery in 65 of 120 patients with metabolic acidemia. The primary features of these 65 cases included the occurrence of sentinel events with prolonged deceleration just before delivery, the rapid deterioration of nonemergent category II fetal heart rate tracings before realistic time frames for recognition and intervention, and the failure of recognized fetal heart rate patterns such as variability to identify metabolic acidemia. Conclusions Expert, algorithm-assisted fetal heart rate interpretation has the potential to improve standard clinical performance by facilitating significantly earlier recognition of some tracings that are associated with metabolic acidemia without increasing the rate of operative intervention. However, this improvement is modest. Of infants who are born with metabolic acidemia, only approximately one-half potentially could be identified and have delivery expedited even under ideal circumstances, which are probably not realistic in current US practice. This represents the limits of electronic fetal heart rate monitoring performance. Additional technologies will be necessary if the goal of the prevention of neonatal metabolic acidemia is to be realized.

Objectives: The aim of this study was to compare the visual analyses of fetal heart rate tracings by observers according to recent National Institute of Child Health and Human Development interpretative guidelines both with each other and with those of a computerized fetal heart rate analysis and alerting system. Study Design: One-hour sections of intrapartum fetal heart rate records were analyzed by a computerized monitoring system (Hewlett-Packard TraceVue; HP GmbH, Boblingen, Germany) and by 4 observers (a registered obstetric nurse, a certified nurse-midwife, an obstetrics resident physician, and a physician maternal-fetal medicine faculty member) instructed to use the new National Institute of Child Health and Human Development guidelines. We compared specific alerts, baseline rates, frequencies of accelerations and decelerations, and signal quality assessments generated by the TraceVue system and the observers. Power analysis indicated that 50 tracings were required to detect interobserver and observer-computer agreement levels of 80% ± 10%. Statistical comparisons used κ coefficient, χ 2 test, and analysis of variance with repeated measures as appropriate. Results: Levels of agreement between observer pairs and the computer did not vary significantly across successive 10-minute intervals. Overall levels of interobserver agreement for baseline rate, tracing quality assessment, frequencies of accelerations and decelerations, and alerts ranged from 45% to 99% and were highest for baseline rate and signal loss and lowest for acceleration and deceleration counts. Interobserver agreement for alerts was relatively high (range, 72%-84%), with virtually no difference between any of the observers and the computer (range, 76.9%-79.2%; κ = 0.25). Conclusion: Use of the National Institute of Child Health and Human Development guidelines for visual fetal heart rate interpretation did not increase agreements on most fetal heart rate features beyond those expected by chance or noted in previous reports. These guidelines did appear to blunt some interpretive differences, possibly as a result of observer background. Although levels of agreement on fetal heart rate features differed, agreements on clinical alerts were similar among all observers and a computerized fetal heart rate monitoring system. Computer analysis of fetal heart rate tracings could eliminate interobserver variation that results from visual analysis and could produce more consistent clinical responses to normal and abnormal fetal heart rate patterns. (Am J Obstet Gynecol 2000;183:361-6.)

This study identifies cases of unexpected intrapartum fetal deaths over 20 years in a Canadian tertiary hospital. Of 121,659 births, 82 were intrapartum deaths. Eleven fetuses were considered viable and nonanomalous. Six deaths were deemed ideally preventable. Application of electronic fetal heart rate monitoring and rapid operative delivery may reduce the already low rate of intrapartum fetal deaths.

There is currently no standard national approach to the management of category II fetal heart rate (FHR) patterns, yet such patterns occur in the majority of fetuses in labor. Under such circumstances, it would be difficult to demonstrate the clinical efficacy of FHR monitoring even if this technique had immense intrinsic value, since there has never been a standard hypothesis to test dealing with interpretation and management of these abnormal patterns. We present an algorithm for the management of category II FHR patterns that reflects a synthesis of available evidence and current scientific thought. Use of this algorithm represents one way for the clinician to comply with the standard of care, and may enhance our overall ability to define the benefits of intrapartum FHR monitoring.

Electronic fetal heart rate monitoring was developed to identify fetuses at risk of acidemia for intervention before adverse outcomes. Our objective was to compare the 3-tier system with a 5-tier system in evaluation of fetal acidemia.Retrospective case-control study of patients with a fetal arterial pH7 matched to the next birth that resulted in a pH7.2. Tracings were categorized into 3- and 5-tier systems by a single reviewer. Sensitivities and specificities were calculated for each.Twenty-four cases and 24 controls were identified. The sensitivity for an orange or red tracing was higher than for category III, with more of these in the pH7 group compared with controls (P ≤ .001). There were significantly more green, blue, and yellow tracings in the normal pH group compared with the pH7 group (P = .033, P = .008, P = .023), respectively.The 5-tier system had a better sensitivity than the 3-tier system.

OBJECTIVE: We attempted to determine changes occurring with time in fetal heart rate and its variation in fetuses with intrauterine growth retardation in whom late antepartum fetal heart rate decelerations eventually develop. STUDY DESIGN: Thirteen fetuses with intrauterine growth retardation were studied over a median period of 25 days. One-hour fetal heart rate records were made two to five times per week and were analyzed numerically. Fetal movements were recorded by the women. RESULTS: On average long-term fetal heart rate variation decreased gradually with time and fell below the norm (30 milliseconds) at about the same time decelerations appeared. Mean heart rate showed a slight but statistically significant increase after the occurrence of declerations. There were large interfetal differences in all parameters studied. CONCLUSION: In fetuses with intrauterine growth retardation a decrease in long-term fetal heart rate variation is a rather late sign of impairment that coincides with the occurrence of late decelerations. In the surveillance of the fetus with intrauterine growth retardation it might be most appropriate to use each fetus as its own control.

Fetal heart rate and fetal movements were recorded in 16 uncomplicated near-term pregnancies. The recordings were used to evaluate a system for automated fetal heart rate analysis (Sonicaid System 8000). Fetal rest-activity patterns were considered in the analysis. The mean duration of C2F periods “active sleep," 33 minutes) was significantly greater than that of C1F periods ("quiet sleep," 19 minutes) ( p p Key words

OBJECTIVE: We evaluated the intrapartum fetal heart rate (FHR) patterns in fetuses with congenital heart disease (CHD). STUDY DESIGN: One hundred sixteen cases of fetal CHD were identified at our institute between 2000-2007; 464 fetuses without CHD were used as controls. The incidences of abnormal FHR patterns and umbilical blood gases were compared. RESULTS: More fetuses with CHD showed variant FHR than did control fetuses (46.6% vs 17.7%; P < .01). Cesarean section deliveries that were based on fetal indications were performed more frequently in fetuses with CHD than in control fetuses (12.9% vs 3.2%; P < .01). Isomerism and tetralogy of Fallot were observed frequently with variant FHR. When chromosomal abnormalities and intrauterine growth restriction were excluded, the fetuses with CHD showed more variant FHR than did the control fetuses. CONCLUSION: Fetuses with CHD are more likely to show abnormal FHR patterns than are control fetuses. We suggest that cardiac abnormalities are associated with abnormalities in FHR patterns.

The search for an adequate back-up test for intrapartum fetal heart rate (FHR) monitoring has spanned the entire history of this technology. Although randomized controlled trials (RCTs) of electronic FHR monitoring (EFM) have been disappointing, the expectations may have been unrealistic. The hope that this technology would lower the rate of cerebral palsy from intrapartum asphyxia has not materialized. There is, however, reasonable good evidence that EFM does decreasetherateofperinatalmortality,particularlyearlyinfant death because of hypoxia. Two analyses, 1 a large population analysis 1 and 1 metaanalysis of 9 RCTs 2 and at least 1 RCT 3 have confirmed this reduction in death rates. Clearly, before EFM, intrapartum deaths were relatively common, occurring inapproximately2-3per1000laboringpatients,andnowsuch deaths are rare. Nevertheless, the price we pay for this technology is high. It is a very difficult and hard task to master technology. All studies that have evaluated EFM have shown an increase in cesarean delivery rates in the electronically monitored patients. EFM has created a malpractice nightmare for obstetriciansbecauseoftheunrealisticexpectationthatwecan prevent all cases of neonatal encephalopathy with early operative intervention in hypoxic babies. Perhaps if we examine whatthetechnologycanandcannotdo,theseresultswithEFM

Sixteen vibratory acoustic stimulations were performed in seven normal twin gestations with continuous simultaneous recordings of each fetal heart rate response. All stimulations led to immediate synchronous fetal heart rate accelerations in both fetuses. This is in contrast to coinciding, yet nonsynchronous, spontaneous fetal heart rate accelerations that occur naturally. This observation suggests that different mechanisms are responsible for spontaneous and evoked fetal movements in twin gestations.

Oxygen saturation monitoring (pulse oximetry) has markedly improved medical care in many fields, including anesthesiology, critical care, and newborn intensive care. In obstetrics, fetal heart rate monitoring remains the standard for intrapartum assessment of fetal well-being. Fetal heart rate monitoring is sensitive but nonspecific for detecting fetal compromise. Additional clinical information is needed to discern those fetuses not at risk for development of intrapartum acidosis to avoid unnecessary intervention. Fetal oxygen saturation monitoring is a new technique currently under development. This article reviews the evolution of intrapartum fetal oxygen saturation monitoring and proposes directions for future investigation.

To examine the association between electronic fetal heart rate monitoring and neonatal and infant mortality, as well as neonatal morbidity.We used the United States 2004 linked birth and infant death data. Multivariable log-binomial regression models were fitted to estimate risk ratio for association between electronic fetal heart rate monitoring and mortality, while adjusting for potential confounders.In 2004, 89% of singleton pregnancies had electronic fetal heart rate monitoring. Electronic fetal heart rate monitoring was associated with significantly lower infant mortality (adjusted relative risk, 0.75); this was mainly driven by the lower risk of early neonatal mortality (adjusted relative risk, 0.50). In low-risk pregnancies, electronic fetal heart rate monitoring was associated with decreased risk for Apgar scores4 at 5 minutes (relative risk, 0.54); in high-risk pregnancies, with decreased risk of neonatal seizures (relative risk, 0.65).In the United States, the use of electronic fetal heart rate monitoring was associated with a substantial decrease in early neonatal mortality and morbidity that lowered infant mortality.