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Objective: To investigate whether use of ST analysis of the fetal electrocardiogram (STan) as an adjunct to continuous cardiotocography (CTG) reduces the rate of emergency Cesarean section (EmCS) compared with CTG alone. Methods: This was a randomized controlled trial of patients with a singleton fetus in cephalic presentation at ≥ 36 weeks' gestation, requiring continuous electronic fetal monitoring during labor at a tertiary maternity hospital in Adelaide, Australia, between January 2018 and July 2021. Participants were randomized to undergo CTG + STan or CTG alone. The calculated sample size was 1818 participants. The primary outcome was EmCS. Secondary outcomes included metabolic acidosis, a composite adverse perinatal outcome, and other maternal and neonatal morbidity and safety outcomes. Results: The present study enrolled 970 women, of whom 967 were included in the primary analysis. EmCS occurred in 107/482 (22.2%) deliveries in the CTG + STan arm and in 107/485 (22.1%) in the CTG arm (adjusted relative risk, 1.02 (95% CI, 0.81–1.27); P = 0.89). There was no difference in the rate of adverse maternal or neonatal outcomes between arms. Conclusions: The addition of STan as an adjunct to continuous CTG did not reduce the EmCS rate. The smaller‐than‐anticipated sample size meant that this study was underpowered to detect absolute differences of ≤ 5% and, therefore, this negative finding could be due to a Type‐2 error. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Purpose: The aim was to investigate if intrapartum monitoring with cardiotocography (CTG) in combination with ST analysis (STAN) results in an improved perinatal outcome. Methods: We performed a two-center randomized trial. 1013 women with term fetuses in cephalic presentation entered the trial. If a CTG showed intermediate or pathological abnormalities, they were offered fetal blood sampling (FBS) and inclusion if the pH value was above 7.25. They were randomized to either CTG + FBS or CTG + STAN. The primary outcome was neonatal metabolic acidosis, defined as umbilical cord arterial blood pH below 7.05, and base excess equal to or below −10. The secondary outcomes included operative vaginal delivery for fetal distress. Results: The rate of metabolic acidosis was 0.8% in the CTG + FBS group and 1.5% in women in the CTG + STAN (P = 0.338). More women in the CTG + STAN group delivered by operative vaginal delivery (25.6% vs 33.5%, P = 0.006). Significantly fewer women in the CTG + STAN group had three to five (28.8% vs 11.0%, P = < 0.001) and six to ten fetal blood samples taken (3.4% vs 0.4%, P = < 0.001). Conclusion: CTG + STAN did not reduce the incidence of neonatal metabolic acidosis compared to CTG + FBS. CTG + STAN was, however, associated with an increased risk of operative vaginal delivery and a reduced use of FBS. If STAN is used for fetal surveillance, we recommend that it is combined with other methods, such as FBS, for confirmation of the need for operative delivery. Clinicaltrials.gov ID: NCT01699646. Date of registration: October 4, 2012 (retrospectively registered). https://clinicaltrials.gov/ct2/show/NCT01699646?id=NCT01699646&draw=2&rank=1 [ABSTRACT FROM AUTHOR]

Abstract Background Cardiotocography is almost ubiquitous in its use in intrapartum care. Although it has been demonstrated that there is some benefit from continuous intrapartum fetal monitoring using cardiotocography, there is also an increased risk of caesarean section which is accompanied by short-term and long-term risks to the mother and child. There is considerable potential to reduce unnecessary operative delivery with up to a 60% false positive diagnosis of fetal distress using cardiotocography alone. ST analysis of the fetal electrocardiogram is a promising adjunct to cardiotocography alone, and permits detection of metabolic acidosis of the fetus, potentially reducing false positive diagnosis of fetal distress. Methods This study will be a single-centre, parallel-group, randomised controlled trial, conducted over 3 years. The primary hypothesis will be that the proportion of women with an emergency caesarean section on ST analysis will not equal that for women on cardiotocography monitoring alone. Participants will be recruited at the Women’s and Children’s Hospital, a high-risk specialty facility with approximately 5000 deliveries per annum. A total of 1818 women will be randomised to the treatment or conventional arm with an allocation ratio of 1:1, stratified by parity. The primary outcome is emergency caesarean section (yes/no). Statistical analysis will follow standard methods for randomised trials and will be performed on an intention-to-treat basis. Secondary maternal and neonatal outcomes will also be analysed. Additional study outcomes include psychosocial outcomes, patient preferences and cost-effectiveness. Discussion Approximately 20% of Australian babies are delivered by emergency caesarean section. This will be the first Australian trial to examine ST analysis of the fetal electrocardiogram as an adjunct to cardiotocography as a potential method for reducing this proportion. The trial will be among the first to comprehensively examine ST analysis, taking into account the impact on psychosocial well-being as well as cost-effectiveness. This research will provide Australian evidence for clinical practice and guideline development as well as for policy-makers and consumers to make informed, evidence-based choices about care in labour. Trial registration ANZCTR, ACTRN1261800006268. Registered on 19 January 2018.

Introduction: Recent developments have produced new CTG classification systems and the question is to what extent these may affect the model of FHR + ST interpretation? The two new systems (FIGO2015 and SSOG2017) classify FHR + ST events differently from the current CTG classification system used in the STAN interpretation algorithm (STAN2007). Aim: Identify the predominant FHR patterns in connection with ST events in cases of cord artery metabolic acidosis missed by the different CTG classification systems. Indicate to what extent STAN clinical guidelines could be modified enhancing the sensitivity. Provide a pathophysiological rationale. Material and methods: Forty-four cases with umbilical cord artery metabolic acidosis were retrieved from a European multicenter database. Significant FHR + ST events were evaluated post hoc in consensus by an expert panel. Results: Eighteen cases were not identified as in need of intervention and regarded as negative in the sensitivity analysis. In 12 cases, ST changes occurred but the CTG was regarded as reassuring. Visual analysis of the FHR + ST tracings revealed specific FHR patterns: Conclusion: These findings indicate FHR + ST analysis may be undertaken regardless of CTG classification system provided there is a more physiologically oriented approach to FHR assessment in connection with an ST event. [ABSTRACT FROM AUTHOR]

In the context of networked education, the subjective behaviour in the field of education, the interaction between teachers and students, and the educational environment in which the subject is located have a comprehensive impact on the teaching mode of psychology in colleges and universities. The multimedia teaching environment is one of the typical environmental types. This paper investigates the current situation of college psychological teaching mode in the multimedia teaching environment from the quantitative perspective, analyzes the psychological teaching mode and classroom interactive speech behaviour in colleges and universities, and compiles the reliability and validity. The high multimedia teaching environment scale discusses the key factors affecting the teaching mode of psychology in colleges and universities from the perspective of statistics, and then puts forward some suggestions for optimizing the teaching mode of psychology in colleges and universities. [ABSTRACT FROM AUTHOR]

Introduction: The updated intrapartum cardiotocography (CTG) classification system by FIGO in 2015 (FIGO2015) and the FIGO2015-approached classification by the Swedish Society of Obstetricians and Gynecologist in 2017 (SSOG2017) are not harmonized with the fetal ECG ST analysis (STAN) algorithm from 2007 (STAN2007). The study aimed to reveal homogeneity and agreement between the systems in classifying CTG and ST events, and relate them to maternal and perinatal outcomes.Material and Methods: Among CTG traces with ST events, 100 traces originally classified as normal, 100 as suspicious and 100 as pathological were randomly selected from a STAN database and classified by two experts in consensus. Homogeneity and agreement statistics between the CTG classifications were performed. Maternal and perinatal outcomes were evaluated in cases with clinically hidden ST data (n = 151). A two-tailed p < 0.05 was regarded as significant.Results: For CTG classes, the heterogeneity was significant between the old and new systems, and agreements were moderate to strong (proportion of agreement, kappa index 0.70-0.86). Between the new classifications, heterogeneity was significant and agreements strong (0.90, 0.92). For significant ST events, heterogeneities were significant and agreements moderate to almost perfect (STAN2007 vs. FIGO2015 0.86, 0.72; STAN2007 vs. SSOG2017 0.92, 0.84; FIGO2015 vs. SSOG2017 0.94, 0.87). Significant ST events occurred more often combined with STAN2007 than with FIGO2015 classification, but not with SSOG2017; correct identification of adverse outcomes was not significantly different between the systems.Conclusion: There are discrepancies in the classification of CTG patterns and significant ST events between the old and new systems. The clinical relevance of the findings remains to be shown. [ABSTRACT FROM AUTHOR]

Objective: Each pregravidic, gestational or intrapartum complication may, per se, have a different impact on the operative delivery rate, regardless of which fetal monitoring system was adopted. We wanted to verify if CTG plus ST interval analysis (STAN) of fetal ECG might be able to reduce the number of operative delivery for fetal distress in high-risk pregnancies compared to low-risk women monitored with CTG alone.Materials and Methods: In this cohort study, we evaluated 100 high-risk pregnancies consecutively with STAN® S31 (Neoventa Medical, Gotenburg, Sweden) and 160 low-risk pregnancies consecutively with continuous CTG (Hewlett Packard, 50 IP, Palo Alto, CA).Results: We found that STAN monitoring, although associated with a higher total operativity rate, both vaginal (11% versus 3.12%, p = 0.015) and cesarean (17% versus 4.37%, p = 0.001), reduced the cesarean section rate performed for fetal distress (29.41% versus 85.71%, p = 0.023) compared with low-risk CTG monitoring group.Conclusion: CTG plus ST interval analysis of fetal ECG reduced the risk of operative cesarean delivery for fetal distress in high-risk gestations. [ABSTRACT FROM AUTHOR]

Intrapartum cardiotocography (CTG) has a high false-positive rate. This has contributed to the rapid increase in obstetric interventions without a strong improvement in perinatal outcomes. We explore the role of ST analysis (STAN®) as an adjunct to CTG in identifying fetal asphyxia during labor. We conclude that STAN® reduces the rate of fetal blood sampling and instrumental vaginal deliveries, and has the potential to reduce the number of Australian operative interventions without compromising neonatal outcome. [ABSTRACT FROM PUBLISHER]

New technical and technological possibilities, which have recently appeared, led to an increase in the interest in thefoetal electrocardiography. Thanks to the construction of special electrodes, the method of direct electrocardiography wasimplemented into general use in the intrapartum supervision of the condition of the foetus. The analysis of the directfoetal electrocardiograms may turn out to be a more precise diagnostic method with a greater prediction value than cardiotocography when it comes to the condition of the foetus and the newborn. Many works indicate an increase in theimportance of the supervision by combining both methods.The aim of this study was to analyse changes of the ST segment of the foetal electrocardiogram (FECG)monitored using STAN®S21 and their correlations with levels of aspartate aminotransferase and alanineaminotransferase. We also analysed AST, ALT correlation with the pH value. We had 54 patients divided into threegroups. Group one included 54 diabetic patients at the age of 30-34. Group two comprised 15 diabetic patients atthe age of 35-39 and group three included 6 patients more than 40 years of age. For intrapartum monitoring we used the STAN®S21 system. The results were as follows: in diabetic patients at theage of 30-43, changes of the ST segment of FECG correlated with the higher level of AST and ALT. The higher level ofAST correlated with the lower pH value. We did not notice any correlations of AST and ALT with ST segment changes.

Objective: Maternal obesity affects one in every five women giving birth worldwide. This condition is associated with adverse perinatal outcomes, as well as increased morbidity and mortality for mother and offspring.Methods: We carried out a prospective study at the University of Pecs Medical Center, Pecs, Hungary, between 1 January 2013 and 1 January 2014. We enrolled 60 obese (body mass index >30 kg/m(2)) low-risk pregnant women and 108 age-, ethnicity-, and parity-matched nonobese pregnant control subjects. The ST segment of the fetal electrocardiogram was assessed by STAN® monitoring. Neonatal outcomes and cord gas analysis of the umbilical vessels were evaluated after birth.Results: No infant with definitive metabolic acidosis was delivered in either group. We observed 32 and 106 ST events in the obese and control group, respectively, but this difference was not statistically significant. To date, none of the infants delivered as part of this study have demonstrated developmental insufficiency.Conclusions: Obesity might not influence the fetal electrocardiogram during labor as an independent risk factor for adverse pregnancy outcomes. Studies with larger cohort sizes are needed to confirm our findings. [ABSTRACT FROM AUTHOR]

Introduction: The objective of this study was to describe the QRS complex of the fetal electrocardiogram (fECG) in relation to fetal presentation, and explore the effect of abnormal QRS on automated ST-interval analysis (STAN).Material and Methods: A case-control study was carried out at a University Hospital in Norway, between the years of 2004-2008. High-risk singleton deliveries with a gestational age >35(+6) weeks, were monitored with cardiotocography and STAN. Cases included breech presentations (n = 433) and controls included cephalic presentations (n = 433). The main outcome measures were QRS-complex abnormalities and fECG abnormalities.Results: An abnormal QRS complex was found in 13.9% of the cases and 16.6% of the controls (p = 0.257). Split R (8.4%) and deep S (8.2%) were the most common abnormalities, and deep Q (4.4% vs. 0.7%, p ≤ 0.001) and split Q (1.8% vs. 0, p ≤ 0.005) were more common in breech than in cephalic presentations. QRS abnormalities impacted on the fECG in 114/866 (13.2%) of the total population. The most common finding was an ambiguous placement of R and S in cases of a split vector (n = 112, 12.9%). Deviance of the ECG baseline above null occurred less frequently (n = 33, 3.8%), and was more common in breech presentation (5.3 vs. 2.3%, p = 0.021). ST events due to an erroneous identification of the QRS vectors and/or a misplacement of the ECG baseline were found in 26 (3.0%) fetuses, with no significant difference in frequency between cases and controls.Conclusions: The appearance of the QRS complex of fECG is dependent upon the fetal presentation. QRS abnormalities impact automated fECG tracing and subsequent ST analysis. Clinicians should be aware of this finding in clinical practice. [ABSTRACT FROM AUTHOR]

Key content ST analysis ( STAN) involves a combination of fetal heart rate interpretation and analysis of the fetal electrocardiogram., STAN has been available for over 5 years in the UK and is used in some, but not all, maternity units., STAN aims to reduce the incidence of fetal acidaemia and hypoxia by identifying these earlier and with greater sensitivity than cardiotocography ( CTG) alone., Learning objectives To be familiar with the background theory and evidence for the use of STAN., To learn the principles for interpretation of the STAN trace., To review practical tips for STAN application and use of STAN monitors., Ethical issues STAN interpretation is currently not part of the RCOG curriculum for obstetrics and gynaecology trainees., Trainees may rotate to a unit that uses STAN routinely and be expected to participate in its use with minimal training. [ABSTRACT FROM AUTHOR]

We appraised the methodology, execution and quality of the five published meta-analyses that are based on the five randomized controlled trials which compared cardiotocography ( CTG)+ ST analysis to cardiotocography. The meta-analyses contained errors, either created de novo in handling of original data or from a failure to recognize essential differences among the randomized controlled trials, particularly in their inclusion criteria and outcome parameters. No meta-analysis contained complete and relevant data from all five randomized controlled trials. We believe that one randomized controlled trial excluded in two of the meta-analyses should have been included, whereas one randomized controlled trial that was included in all meta-analyses, should have been excluded. After correction of the uncovered errors and exclusion of the randomized controlled trial that we deemed inappropriate, our new meta-analysis showed that CTG+ ST monitoring significantly reduces the fetal scalp blood sampling usage (risk ratio 0.64; 95% confidence interval 0.47-0.88), total operative delivery rate (0.93; 0.88-0.99) and metabolic acidosis rate (0.61; 0.41-0.91). [ABSTRACT FROM AUTHOR]

Five randomized controlled trials have been published on intrapartum fetal heart rate monitoring with ST analysis of the fetal electrocardiogram, but the debate on its usefulness has not yet been ended. We consider ST analysis a useful and cost-effective addition to conventional fetal heart rate monitoring. We will provide support for this opinion by discussing the pathophysiology of ST changes in relation to fetal asphyxia, the results of the randomized controlled trials and numerous meta-analyses of these randomized controlled trials and trends in fetal outcome in hospitals in different countries following the introduction of the ST technology in the labor ward. [ABSTRACT FROM AUTHOR]

We reappraised the five randomized controlled trials that compared cardiotocography plus ECG ST interval analysis ( CTG+ ST) vs. cardiotocography. The numbers enrolled ranged from 5681 (Dutch randomized controlled trial) to 799 (French randomized controlled trial). The Swedish randomized controlled trial ( n = 5049) was the only trial adequately powered to show a difference in metabolic acidosis, and the Plymouth randomized controlled trial ( n = 2434) was only powered to show a difference in operative delivery for fetal distress. There were considerable differences in study design: the French randomized controlled trial used different inclusion criteria, and the Finnish randomized controlled trial ( n = 1483) used a different metabolic acidosis definition. In the CTG+ ST study arms, the larger Plymouth, Swedish and Dutch trials showed lower operative delivery and metabolic acidosis rates, whereas the smaller Finnish and French trials showed minor differences in operative delivery and higher metabolic acidosis rates. We conclude that the differences in outcomes are likely due to the considerable differences in study design and size. This will enhance heterogeneity effects in any subsequent meta-analysis. [ABSTRACT FROM AUTHOR]

A retrospective observational study on a sample of 13,413 deliveries analysed the effect of a withdrawal of the CTG additional diagnostic methods of fetal hypoxia (fetal pulse oximetry and ST analysis of the fetal ECG) on operative delivery rates and frequency of the umbilical arterial pH < 7.15. Following the withdrawal, obstetricians are more likely to perform caesarean sections for fetal hypoxia (OR 2.23, 95% CI 1.94-2.55, p < 0.0001 ) and labour dystocia (OR 1.45, 95% CI 1.18-1.77, p = 0.0003), which increases the overall caesarean rate (OR 1.49, 95% CI 1.38-1.61, p < 0.0001 ), although decreases the incidence of birth umbilical arterial pH < 7.15 (OR 0.43, 95% CI 0.22-0.85, p = 0.015). This also leads to the significant decline in overall frequency of instrumental vaginal deliveries (OR 0.58, 95% CI 0.48-0.71). In order to decrease the overall caesarean rate, obstetricians need to be supported by more accurate and possibly automated diagnostic tools for intrapartum fetal hypoxia. [ABSTRACT FROM AUTHOR]

Objective To evaluate the clinical use of ST analysis (STAN) for intrapartum monitoring of high-risk pregnancies. Design Prospective observational study. Setting University hospital, Norway, 2004-2008. Population Singleton pregnancies with a gestational age above 35+6 weeks. Methods Analysis of maternal and neonatal outcomes for all deliveries according to the method of intrapartum monitoring. Main outcome measures Prevalence of cord metabolic acidosis (pH < 7.05, extracellular fluid base deficit (extracellular fluid) >12 mmol/L). Results Of 23 203 deliveries, 6010 (25.9%) were monitored with STAN. Fetal blood sampling was performed in 146 (2.4%) of the 6010 cases. During the study period, the prevalence of cord metabolic acidosis and moderate cord acidosis (pH < 7.15) decreased in STAN-monitored deliveries from 1.4 to 0.3% ( p = 0.01) and from 16.4 to 11.7% ( p = 0.001), respectively. The prevalence of moderate and severe neonatal encephalopathy was 0.38%. In the birth population, the proportion of cesarean deliveries decreased from 10.1 to 8.8%. The risk of emergency cesarean section after STAN monitoring compared with those monitored with auscultation/cardiotocography was high (odds ratio 5.4, 95% confidence interval = 4.9-6.1) but remained stable during the study period. Conclusions ST analysis is a useful tool for identification of fetuses at risk of intrapartum hypoxia. Despite the restricted use of fetal blood sampling, we found a low proportion of cord metabolic acidosis and newborn morbidity. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To evaluate how deviations from STAN guidelines contribute to operative delivery for suspected fetal distress in a high-risk population. Study design: This retrospective cohort study was conducted in a tertiary referral center with about 3000 deliveries a year. During the study period, STAN usage rate was 15.2%. All consecutive patients monitored with STAN who had an operative delivery for suspected fetal distress were included in the index group. Patients who delivered spontaneously or had an operative delivery for any reason other than suspected fetal distress were included as controls. Case review was performed by three referent obstetricians for STAN technology blinded to neonatal outcomes. Main outcome was agreement between decision made and decision recommended by STAN clinical guidelines. Secondary outcomes were reasons explaining guideline deviation and ST event to birth interval in cases with a significant ST event. Results: Eighty-three patients were included in each group. Decision made was consistent with STAN clinical guidelines in 124 patients (74.7%): 50 patients (60.2%) in the index group and 74 patients (89.2%) in the control group (p <0.05). Among these patients, no fetal metabolic acidosis was reported. Decision made was not consistent with STAN labor management guidelines in 42 patients (24.3%): 33 patients (39.8%) in the index group and 9 (10.8%) in the control group (p <0.05). Including ST event to birth interval, interventions were outwith STAN clinical guidelines in 51.4% of patients with suspected fetal distress. CTG misclassification was involved in over 75% of cases. Conclusion: STAN guideline deviations contribute to an increased operative delivery rate in patients with suspected fetal distress and normal neonatal outcomes. Guideline deviations are more frequent in patients with suspected fetal distress than in controls. CTG misclassification was the leading cause of guideline deviation. STAN guideline deviations may contribute to alter STAN specificity. [Copyright &y& Elsevier]

Objectives: This paper describes a methodology for the monitoring of the fetal cardiac health status during pregnancy, through the effective and non-invasive monitoring of the abdominal ECG signals (abdECG) of the mother.Methods: For this purpose, a three-stage methodology has been developed. In the first stage, the fetal heart rate (fHR) is extracted from the abdECG signals, using nonlinear analysis. Also, the eliminated ECG (eECG) is calculated, which is the abdECG after the maternal QRSs elimination. In the second stage, a blind source separation technique is applied to the eECG signals and the fetal ECG (fECG) is obtained. Finally, monitoring of the fetus is implemented using features extracted from the fHR and fECG, such as the T/QRS ratio and the characterization of the fetal ST waveforms.Results: The methodology is evaluated using a dataset of simulated multichannel abdECG signals: 94.79% accuracy for fHR extraction, 92.49% accuracy in T/QRS ratio calculation and 79.87% in ST waveform classification.Conclusions: The novel non-invasive proposed methodology is advantageous since it offers automated identification of fHR and fECG and automated ST waveform analysis, exhibiting a high diagnostic accuracy. [ABSTRACT FROM AUTHOR]

Continuous intrapartum cardiotocography (CTG) augmented by fetal ECG ST segment analysis (STAN) has the potential to reduce the rates of neonatal metabolic acidosis and obstetric interventions. STAN was introduced at Ninewells Hospital, Dundee in October 2007. Data were collected prospectively from all women who received continuous intrapartum CTG and STAN between 1 October 2007 and 31 March 2008. A total of 253 women had continuous CTG and STAN. The median number of ST events was one (range = 1–32). Most (556/719, 77%) ST events were associated with a normal CTG; 46/144 (32%) patients with an ST event required immediate action. Three of the 253 (1.2%) women were delivered based on an ST event with a normal CTG; four (1.5%) had severe neonatal metabolic acidosis and all four cases had intrapartum ST events and were not managed according to STAN guidelines. ST events are common but the majority of ST events require no action. The high incidence of false-positive ST events might have contributed to the failure to act when a significant ST event occurred. [ABSTRACT FROM AUTHOR]

Objective The objective of this study was to quantify inter- and intra-observer agreement on classification of the intrapartum cardiotocogram (CTG) and decision to intervene following STAN guidelines. Design A prospective, observational study. Setting Obstetrics Department of a tertiary referral hospital. Population STAN recordings of 73 women after 36 weeks of gestation with a high-risk pregnancy, induced or oxytocin-augmented labour, meconium-stained amniotic fluid or epidural analgesia. Methods Six observers classified 73 STAN recordings and decided if and when they would suggest an intervention. Proportions of specific agreement (Ps) and kappa values ( K) were calculated. Main outcome measures Agreement upon classification of the intrapartum CTG and decision to perform an intervention. Results Agreement for classification of a normal and a (pre)terminal CTG was good (Ps range 0.50–0.84), but poor for the intermediary and abnormal CTG (Ps range 0.34–0.56). Agreement on the decision to intervene was higher, especially on the decision to perform ‘no intervention’ (Ps range 0.76–0.94). Overall inter-observer agreement on the decision to intervene was considered moderate in five of six observer combinations according to the kappa ( K range 0.42–0.73). Intra-observer agreement for CTG classification and decision to intervene was moderate ( K range 0.52–0.67 and 0.61–0.75). Conclusions Inter-observer agreement on classification of the intrapartum CTG is poor, but addition of information regarding fetal electrocardiogram, especially in case of intermediary or abnormal CTG traces, results in a more standardised decision to intervene. [ABSTRACT FROM AUTHOR]

Objective To assess the cost-effectiveness of the use of cardiotocography (CTG) complemented with fetal electrocardiography and ST analysis compared with the use of CTG alone in term deliveries when a decision has been made to use fetal monitoring with a scalp electrode. Design A cost-effectiveness analysis based on a probabilistic decision model incorporating relevant strategies and lifelong outcomes. Setting Maternity wards in Sweden. Population Women with term fetuses after a clinical decision had been made to apply a fetal scalp electrode for internal CTG. Methods A decision model was used to compare the costs and effects of two different treatment strategies. Baseline estimates were derived from the literature. Discounted costs and quality-adjusted life years (QALYs) were simulated over a lifetime horizon using a probabilistic model. Main outcome measures QALYs, incremental costs, and cost per QALY gained expressed as incremental cost-effectiveness ratio (ICER). Results The analysis found an incremental effect of 0.005 QALYs for ST analysis compared with CTG; the ST analysis strategy was also moreover associated with a €56 decrease in costs, thus dominating the CTG strategy. The probability that ST analysis is cost-effective in comparison with CTG is high, irrespective of the willingness-to-pay value for a QALY. Conclusions Compared with CTG alone, ST analysis is cost-effective when used in term high-risk deliveries in which there is a need for internal fetal monitoring. [ABSTRACT FROM AUTHOR]

Objective To assess the occurrence of ST-interval segment changes of the fetal electrocardiogram (ECG) and cardiotocographic (CTG) abnormalities preceding acidaemia at birth. Design Case–control study. Setting University hospital labour ward. Sample Newborns with severe cord artery metabolic acidaemia (pH < 7.00 and lactate ≥ 10 mmol/l; n= 24), moderate metabolic acidaemia (pH 7.00–7.09 and lactate ≥ 10; n= 48), acidaemia (pH 7.00–7.09; n= 52), pre-acidaemia (pH 7.10–7.19; n= 265), and controls (pH ≥ 7.20; n= 117). Methods Monitoring traces were assessed blinded to outcome. Main outcome measures CTG and ST changes. Results Any ST event occurred significantly more often among cases with severe (79%) and moderate (75%) metabolic acidaemia than among controls (50%). The difference was restricted to baseline T/QRS rises and to the second stage of labour, during which any event only occurred significantly more often among cases with severe metabolic acidaemia (62%) than among controls (38%). ST events coincided with abnormal CTG patterns in 67, 44, 40, and 28% of cases with severe and moderate metabolic acidaemia, acidaemia, and pre-acidaemia, respectively, and in 12% of controls. ST events with intermediary CTG were similarly frequent in the case groups (0–6%) as in the controls (4%). The ST guidelines stated intervention in 96, 62, 73, and 49% of case groups and 23% of controls. Conclusions Only two of three cases with severe and less than half of cases with moderate metabolic acidaemia were preceded by ST events coinciding with CTG abnormalities. It is therefore important to intervene for long-lasting, rapidly deteriorating or marked (preterminal) CTG abnormalities, also in the absence of ST events. [ABSTRACT FROM AUTHOR]

Objective. The objective of our study was to test the hypothesis that the availability and selective use of STAN® in conjunction with cardiotocography for intrapartum monitoring, lowers the incidence of operative deliveries for fetal distress. Design. Observational study. Setting. Delivery suite of the National University Hospital, Singapore. Methods. The data regarding intrapartum cesarean sections and instrumental vaginal deliveries for presumed fetal distress and the condition of the neonate at birth (Apgar scores at one and five minutes and admission to neonatal intensive care unit (NICU) were collected over two consecutive three-year periods. In the first triennium, only external cardiotocography was used for intrapartum fetal surveillance and in the second triennium STAN® monitoring was available for use in the delivery suite. Results. With the availability and selective use of STAN® monitoring, there was a significant decrease in the number of instrumental deliveries for fetal distress (from 66 out of 520 (0.9%) to 36 out of 474 (0.5%), p<0.025), the number of admissions to the NICU (from 418 (5.6%) to 311 (4.6%), p<0.01) and the number of neonates with Apgar score of seven or less at five minutes (from 192 (2.6%), p<0.001 to 113 (1.7%), p<0.001). There was no significant difference in the incidence of emergency cesarean sections for fetal distress during the two time periods. Conclusion. Intrapartum monitoring of term fetuses with cardiotocography combined with selective use of ST analysis leads to a significant reduction in the number of operative deliveries for suspected fetal distress with no adverse effect on neonatal outcome. [ABSTRACT FROM AUTHOR]

Objective To examine detailed intrapartum events in cases of neonatal metabolic acidosis despite monitoring using STAN® (cardiotocography [CTG] plus ST waveform analysis of fetal electrocardiogram [ECG]). Design Retrospective case review. Setting High-risk pregnancies monitored by STAN®. Methods Case note review was performed in newborns with metabolic acidosis where no significant ST changes in the fetal ECG occurred prior to birth. Main outcome measures Metabolic acidosis. Results Detailed review of three cases identified poor signal quality, difficulties in CTG interpretation, failure to comply with STAN® clinical guidelines and deterioration of the CTG without ECG alert as the leading causes of these adverse outcomes. Conclusions The cases illustrate some of the pitfalls associated with the clinical application of the STAN® technology which prevent severe metabolic acidosis being eradicated completely. It may be useful to expand the STAN® guidelines protocol towards the identification of exceptional clinical situations, such as in our cases, and towards appropriate additional interventions, as this may lead to a further reduction in adverse neonatal outcomes. [ABSTRACT FROM AUTHOR]

Objective: To determine the diagnostic value of fetal ST-segment analysis (STAN) in predicting neonatal acidosis.Methods: The STAN S21 was used to monitor singleton fetuses in labor with abnormal FHR. Physicians later reviewed tracings to identify any ST events dictating intervention. Outcome measures were umbilical artery pH< or =7.15 and pH< or =7.05 at birth. The sensitivity, specificity, PPV, and NPV of a significant ST event to predict both outcomes were calculated.Results: Analysis included 411 women. Sensitivity of a significant ST event for screening pH< or =7.15 (21.9%) was 38% (41/108), specificity 83% (252/303), PPV 45% (41/92) and NPV 79% (252/319), and for pH< or =7.05, it was (3.4%), 62.5% (10/16), 79% (313/395), 11% (10/92), and 98% (313/319), respectively.Conclusion: In a population with abnormal FHR in labor, STAN sensitivity is moderate (almost 40%) for predicting pH< or =7.15 and better (almost 60%) for more severe acidosis (pH< or =7.05). [ABSTRACT FROM AUTHOR]

Objective To examine whether intrapartum monitoring by means of automatic ST analysis (STAN) of fetal electrocardiography could reduce the rate of neonatal acidemia and the rate of operative intervention during labour, compared with monitoring by means of cardiotocography (CTG). Design Randomised controlled trial. Setting Labour ward in tertiary-level university hospital. Sample A total of 1483 women in active labour with singleton term fetus in cephalic presentation. Methods Women were randomly assigned to be monitored either by STAN or by CTG. Fetal blood sampling (FBS) was optional in both groups. Main outcome measures Neonatal acidemia (umbilical artery pH <7.10), neonatal metabolic acidosis (umbilical artery pH <7.05 and base excess <-12 mmol/l) and operative interventions: caesarean section rate, vacuum outlet (VO) rate and FBS rate. Results There were no statistically significant differences between the STAN group and CTG group in the incidence of neonatal acidemia (5.8 versus 4.7%) or metabolic acidosis (1.7 versus 0.7%). The caesarean section rate (6.4 versus 4.7%) and the VO rate (9.5 versus 10.7%) were also similar in the STAN and CTG groups. The incidence of FBS was lower (P < 0.001) in the STAN group (7.0%) than in the CTG group (15.6%). Conclusions Intrapartum fetal monitoring by means of automatic STAN did not improve the neonatal outcome or decrease the caesarean section rate. However, the need for FBS during labour was lower in the STAN group. [ABSTRACT FROM AUTHOR]

Background: Fetal pulse oximetry measures arterial oxygen saturation during delivery. The fetal electrocardiogram STAN S21 analyzes the repolarisation segment of ECG (ST) waveform, which is altered by the intramyocardial potassium release resulting from metabolic acidemia. This study aimed to evaluate the feasibility of a simultaneous application of pulse oximetry and fetal electrocardiography and to estimate any agreement between both methods indicating fetal compromise.Methods: In an observational trial 35 fetuses were simultaneously monitored by pulse oximetry (OBS-500) and electrocardiography. The evaluation focused on signal output and on the coincidence of desaturation in fetal pulse oximetry and on ST events. Desaturation was defined as a drop of at least 20% of oxygen saturation from base line level occurring within 1 min (steep desaturation) or duration of time (s) with oxygen saturation below the threshold of 30%. Statistical analysis was performed with the Mann-Whitney U-test for continuous variables.Results: Signal output of the simultaneous application of both sensors was not significantly reduced in the electrocardiogram and in pulse oximetry (8% vs. 12% reduction). In 15 of the 35 fetuses, ST events indicating fetal hypoxia occurred. In these cases, pulse oximetry showed significantly more episodes of desaturation in comparison with fetuses without ST events. Median saturation during the ST events was significantly lower than in the recordings without ST events (60% vs. 74%, p < 0.05). In the umbilical artery these neonates showed significantly lower pH (7.19 vs. 7.33, p < 0.001), significantly higher lactate (5.1 vs. 3.4 mmol/l, p < 0.05) and significantly lower base deficit (-9.4mmol/l vs. -4.0 mmol/l, p < 0.001) levels.Conclusions: The combination of fetal pulse oximetry and fetal electrocardiography appears feasible and indicates signs of intermittent hypoxia. These findings may encourage the development of technology that combines these different methods of monitoring. [ABSTRACT FROM AUTHOR]

Long-term ambulatory electrocardiographic monitoring [AEM] of the ST segment is clinically the most practical test for the documentation and quantification of myocardial ischaemia. However, there is still some controversy about the validity of ST measurements in Holter monitoring. Therefore, in the present study, in a series of 26 patients with angiographically proven (> 70%) coronary heart disease and a positive exercise electrocardiogram, the number, duration and the severity of symptomatic and asymptomatic ischaemic episodes were measured by (1) the ST change at the J point, (2) the ST change 0.07–0.10 s after the J point (immediately before the T wave), (3) the change of the slope of the ST segment, and (4) the area under the ST segment, with a Reynolds Pathfinder III and compared with visual analysis. At the J point (1) there were a total of 264 episodes with a duration of 3947 min and a maximum of 0.35 mV, beforethe T wave (2) 276 episodes with a duration of 3440 min and a maximal change of 0.40 mV; looking at the slope of the ST segment (3) the figures were 118, 1041 min and regarding the area under the ST segment they were 198, 2385 min. In conclusion, ST deviations are safely detected by automated analysis of the ST segment. Compared with visual analysis (220 episodes), deviation ofthe ST1 (J point) and ST2 point (80 ms thereafter) overestimate the incidence of true ischaemic ST depression by about 20%. The presence of a negative slope and an area of ST deviation of more than 10 μVs underestimates the presence of ischaemic episodes by about 50% and 10%, respectively. The presence of ST1 deflection >0.1 mV plus ST2 deflection of <0.1 mV predicts the true ischaemic ST depression most accurately (compared with visual analysis). [ABSTRACT FROM PUBLISHER]