Intrapartum fetal monitoring has been criticized for the lack of evidence of improvement in fetal outcome despite causing increased operative intervention. Paradoxically, cardiotocography （CTG） has been a major driv...Intrapartum fetal monitoring has been criticized for the lack of evidence of improvement in fetal outcome despite causing increased operative intervention. Paradoxically, cardiotocography （CTG） has been a major driver for litigation for neonatal neurological injury. This analytical review tries to explore why extensive clinical studies and trials over 50 years have failed to demonstrate or bring about signifcant improvement in intrapartum fetal monitoring. There seems a need for significant reform. International congruence on most aspects of CTG interpretation [defnitions of fetal heart rate （FHR） parameters, CTG recording speed, 3-tier systems, etc .] is highly desirable to facilitate future meaningful clinical studies, evaluation and progress in this field. The FHR changes are non-specific and poor surrogate for fetal well-being. As a compromise for maintaining low false-negative results for fetal acidemia, a high false-positive value may have to be accepted. The need for redefning the place of adjuvant tests of fetal well-being like fetal blood sampling or fetal electrocardiography （ECG） is discussed. The FHR decelerations are often deterministic （center-stage） in CTG interpretation and 3-tier categorization. It is discussed if their scientifc and physiological classifcation （avoiding framing and confirmation biases） may be best based on time relationship to uterine contractions alone. This may provide a more sound foundation which could improve the reliability and further evolution of 3-tier systems. Results of several trials of fetal ECG （STAN） have been inconclusive and a need for a fresh approach or strategy is considered. It is hoped that the long anticipated Computer-aided analysis of CTG will be more objective and reliable （overcome human factors） and will offer valuable support or may eventually replace visual CTG interpretation. In any case, the recording and archiving all CTGs digitally and testing cord blood gases routinely in every delivery would be highly desirable for future research. This would facilitate well designed retrospective studies which can be very informative especially when prospective randomised controlled trials are often diffcult and resource-intensive.展开更多
Cardiotocography measures the human fetal heart rate and uterine activity using ultrasound.While it has been a mainstay in antepartum care since the 1960s,cardiotocograms consist of complex signals that have proven di...Cardiotocography measures the human fetal heart rate and uterine activity using ultrasound.While it has been a mainstay in antepartum care since the 1960s,cardiotocograms consist of complex signals that have proven difficult for clinicians to interpret accurately and as such clinical inference is often difficult and unreliable.Previous attempts at codifying approaches to analyzing the features within these signals have failed to demonstrate reliability or gain sufficient traction.Since the early 1990s,the Dawes-Redman system of automated computer analysis of cardiotocography signals has enabled robust analysis of cardiotocographic signal features,employing empirically-derived criteria for assessing fetal wellbeing in the antepartum.Over the past 30 years,the Dawes-Redman system has been iteratively updated,now incorporating analyses from over 100,000 pregnancies.In this review,we examine the history of cardiotocography,signal processing methodologies and feature identification,the development of the Dawes-Redman system,and its clinical applications.展开更多
文摘Intrapartum fetal monitoring has been criticized for the lack of evidence of improvement in fetal outcome despite causing increased operative intervention. Paradoxically, cardiotocography （CTG） has been a major driver for litigation for neonatal neurological injury. This analytical review tries to explore why extensive clinical studies and trials over 50 years have failed to demonstrate or bring about signifcant improvement in intrapartum fetal monitoring. There seems a need for significant reform. International congruence on most aspects of CTG interpretation [defnitions of fetal heart rate （FHR） parameters, CTG recording speed, 3-tier systems, etc .] is highly desirable to facilitate future meaningful clinical studies, evaluation and progress in this field. The FHR changes are non-specific and poor surrogate for fetal well-being. As a compromise for maintaining low false-negative results for fetal acidemia, a high false-positive value may have to be accepted. The need for redefning the place of adjuvant tests of fetal well-being like fetal blood sampling or fetal electrocardiography （ECG） is discussed. The FHR decelerations are often deterministic （center-stage） in CTG interpretation and 3-tier categorization. It is discussed if their scientifc and physiological classifcation （avoiding framing and confirmation biases） may be best based on time relationship to uterine contractions alone. This may provide a more sound foundation which could improve the reliability and further evolution of 3-tier systems. Results of several trials of fetal ECG （STAN） have been inconclusive and a need for a fresh approach or strategy is considered. It is hoped that the long anticipated Computer-aided analysis of CTG will be more objective and reliable （overcome human factors） and will offer valuable support or may eventually replace visual CTG interpretation. In any case, the recording and archiving all CTGs digitally and testing cord blood gases routinely in every delivery would be highly desirable for future research. This would facilitate well designed retrospective studies which can be very informative especially when prospective randomised controlled trials are often diffcult and resource-intensive.
文摘Cardiotocography measures the human fetal heart rate and uterine activity using ultrasound.While it has been a mainstay in antepartum care since the 1960s,cardiotocograms consist of complex signals that have proven difficult for clinicians to interpret accurately and as such clinical inference is often difficult and unreliable.Previous attempts at codifying approaches to analyzing the features within these signals have failed to demonstrate reliability or gain sufficient traction.Since the early 1990s,the Dawes-Redman system of automated computer analysis of cardiotocography signals has enabled robust analysis of cardiotocographic signal features,employing empirically-derived criteria for assessing fetal wellbeing in the antepartum.Over the past 30 years,the Dawes-Redman system has been iteratively updated,now incorporating analyses from over 100,000 pregnancies.In this review,we examine the history of cardiotocography,signal processing methodologies and feature identification,the development of the Dawes-Redman system,and its clinical applications.
