Intrapartum Fetal Heart Rate: A Possible Predictor of Neonatal Acidemia and APGAR Score

Labor management and neonatal outcomes in cardiotocography categories II and III (Review)

The safe care of both mothers and fetuses during labor is a primary goal of all health professionals. The assessment of fetal oxygenation and well-being is a key aspect of perinatal care provided. Fetal heart rate (FHR) auscultation became part of daily obstetric practice in a number of countries during the 20th century and remains a key method of fetal monitoring, particularly in low-risk pregnancies. Cardiotocography (CTG) is the continuous monitoring and recording of the FHR and uterine myometrial activity, making it possible to assess the fetal condition. It therefore plays a critical role in the detection of fetal hypoxia during labor, a condition directly related to short- and long-term complications in the newborn. Herein, particular reference is made to the management of CTG category II and III standards, as well as to the handling of childbirth. In addition, specific FHR patterns are associated with immediate neonatal outcomes based on updated studies conducted worldwide. Finally, the prognostic significance of CTG and its potential as a prospective avenue for further investigation are also highlighted herein. Given that the misinterpretation of CTG findings is the most common cause of medical-legal responsibility, this knowledge field requires more emphasis and attention. The aim of the present review was to further deepen the knowledge on issues that mainly concern the safety and monitoring of pregnant women and fetuses during childbirth.

Approaches to Preventing Intrapartum Fetal Injury

Electronic fetal monitoring (EFM) was introduced into obstetric practice in 1970 as a test to identify early deterioration of fetal acid-base balance in the expectation that prompt intervention ("rescue") would reduce neonatal morbidity and mortality. Clinical trials using a variety of visual or computer-based classifications and algorithms for intervention have failed repeatedly to demonstrate improved immediate or long-term outcomes with this technique, which has, however, contributed to an increased rate of operative deliveries (deemed "unnecessary"). In this review, we discuss the limitations of current classifications of FHR patterns and management guidelines based on them. We argue that these clinical and computer-based formulations pay too much attention to the detection of systemic fetal acidosis/hypoxia and too little attention not only to the pathophysiology of FHR patterns but to the provenance of fetal neurological injury and to the relationship of intrapartum injury to the condition of the newborn. Although they do not reliably predict fetal acidosis, FHR patterns, properly interpreted in the context of the clinical circumstances, do reliably identify fetal neurological integrity (behavior) and are a biomarker of fetal neurological injury (separate from asphyxia). They provide insight into the mechanisms and trajectory (evolution) of any hypoxic or ischemic threat to the fetus and have particular promise in signaling preventive measures (1) to enhance the outcome, (2) to reduce the frequency of "abnormal" FHR patterns that require urgent intervention, and (3) to inform the decision to provide neuroprotection to the newborn.

Analysis of antepartum cardiotocography based on S/k proportions and probability in 20 minutes

Abstract Objectives: although mortality and perinatal asphyxia in newborns have been considerably reduced, there are still deficiencies in screening and diagnosis methods for intrapartum fetal well being that aim to detect its early alterations. Therefore, the purpose of this research was to apply a methodology based on probability and entropy and confirm its capacity to detect normal and abnormal fetal cardiac dynamics from 20-minute cardiotocographic tracings. Methods: 80 cardiotocographic tracings of pregnant women in the last trimester were collected, of which the minimum and maximum fetal heart rate were evaluated every 10 seconds, as well as its repetitions along with their probability and the diagnostic S/k ratio. Finally, the statistical analysis was carried out to establish the diagnostic capacity of the method concerning the clinical evaluation and interpretation of the cardiotocographic tracing, taken as the Gold Standard. Results: it was confirmed that S/k ratio values differentiated normal from abnormal fetal cardiac dynamics with sensitivity and specificity values of 100% and a Kappa coefficient of 1. Conclusion: the applicability of a diagnostic mathematical method of cardiotocography was confirmed, which suggests its implementation in the clinical context to detect alterations in fetal well-being in 20 minutes.

Distributed Big Data Analytics Method for the Early Prediction of the Neonatal 5-Minute Apgar Score before or during Birth and Ranking the Risk Factors from a National Dataset

One-minute and five-minute Apgar scores are good measures to assess the health status of newborns. A five-minute Apgar score can predict the risk of some disorders such as asphyxia, encephalopathy, cerebral palsy and ADHD. The early prediction of Apgar score before or during birth and ranking the risk factors can be helpful to manage and reduce the probability of birth producing low Apgar scores. Therefore, the main aim of this study is the early prediction of the neonate 5-min Apgar score before or during birth and ranking the risk factors for a big national dataset using big data analytics methods. In this study, a big dataset including 60 features describing birth cases registered in Iranian maternal and neonatal (IMAN) registry from 1 April 2016 to 1 January 2017 is collected. A distributed big data analytics method for the early prediction of neonate Apgar score and a distributed big data feature ranking method for ranking the predictors of neonate Apgar score are proposed in this study. The main aim of this study is to provide the ability to predict birth cases with low Apgar scores by analyzing the features that describe prenatal properties before or during birth. The top 14 features were identified in this study and used for training the classifiers. Our proposed stack ensemble outperforms the compared classifiers with an accuracy of 99.37 ± 1.06, precision of 99.37 ± 1.06, recall of 99.50 ± 0.61 and F-score of 99.41 ± 0.70 (for confidence interval of 95%) to predict low, moderate and high 5-min Apgar scores. Among the top predictors, fetal height around the baby’s head and fetal weight denote fetal growth status. Fetal growth restrictions can lead to low or moderate 5-min Apgar score. Moreover, hospital type and medical science university are healthcare system-related factors that can be managed via improving the quality of healthcare services all over the country.

Factors associated with intrapartum ZigZag pattern of fetal heart rate: A retrospective one-year cohort study of 5150 singleton childbirths

OBJECTIVES

Recent studies suggest that intrapartum ZigZag pattern of fetal heart rate (FHR) is significantly associated with cord blood acidaemia and neonatal complications. For the clinical significance of this pattern, it is mandatory that ZigZag episodes in cardiotocographic (CTG) recording are correctly identified. The aim of the present study was to examine maternal, fetal and delivery-related factors that could explain the occurrence of ZigZag pattern of FHR during the last 2 h of labour in a large obstetric cohort.

STUDY DESIGN

CTG recordings from 5150 singleton childbirths at ≥33 weeks of gestation during one year were evaluated retrospectively and blinded to pregnancy and neonatal outcomes in a university hospital in Helsinki, Finland. All women in the cohort were in the active phase of labour with regular uterine contractions. ZigZag FHR pattern was defined as FHR baseline amplitude changes of >25 bpm with a duration of 2-30 min. The following maternal, fetal and labour/delivery-related variables were determined: maternal age, obesity (prepregnancy BMI ≥ 30.0 kg/m²), parity, preeclampsia, maternal fever ≥38.0 °C, smoking, gestational age at delivery, fetal sex, birth weight z-score, mode of delivery, and type of onset of labour.

RESULTS

ZigZag pattern occurred in 582/5150 (11.3 %) cases, and only in childbirths after 37 weeks of gestation. Fetal male gender (OR 3.29; 95 % CI 2.70-4.02), nulliparous pregnancy (OR 2.60; 95 % CI 2.15-3.15) and post-term gestational age (≥42 weeks) (OR 1.92; 95 % CI 1.47-2.48) were independently associated with the occurrence of ZigZag pattern. Among the three significant risk factors, clustering of two or three factors was associated with an increase of the ZigZag pattern occurrence risk to 5.0-16.4-fold (95 % CI 3.16-31.60).

CONCLUSIONS

ZigZag pattern occurred in term pregnancies after 37 weeks of gestation only. Fetal male gender, nulliparity and post-term pregnancy are significantly associated with ZigZag FHR pattern during the last two hours of labour. Identification of maternal, fetal and delivery-related variables are imperative in order to interpret correctly the findings of CTG and to prevent adverse neonatal outcome.