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Schifrin BS, Koos BJ, Cohen WR, Soliman M. Approaches to Preventing Intrapartum Fetal Injury. Front Pediatr 2022; 10:915344. [PMID: 36210941 PMCID: PMC9537758 DOI: 10.3389/fped.2022.915344] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Accepted: 06/21/2022] [Indexed: 12/05/2022] Open
Abstract
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.
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Affiliation(s)
- Barry S. Schifrin
- Department of Obstetrics and Gynecology, Western University of Health Sciences, Pomona, CA, United States
| | - Brian J. Koos
- Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, United States
| | - Wayne R. Cohen
- Department of Obstetrics and Gynecology, University of Arizona College of Medicine, Tucson, AZ, United States
| | - Mohamed Soliman
- Department of Obstetrics and Gynecology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA, United States
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Turner JM, Mitchell MD, Kumar S. Reply. Am J Obstet Gynecol 2020; 222:283-284. [PMID: 31733204 DOI: 10.1016/j.ajog.2019.10.105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Accepted: 10/22/2019] [Indexed: 11/19/2022]
Affiliation(s)
- Jessica M Turner
- Mater Research Institute, University of Queensland, Brisbane, Queensland, Australia
| | - Murray D Mitchell
- Institute of Health and Biomedical Innovation, Centre for Children's Health Research, Faculty of Health, Queensland University of Technology, Brisbane, Queensland, Australia
| | - Sailesh Kumar
- Faculty of Medicine, University of Queensland, Brisbane, Queensland, Australia.
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Sholapurkar SL. Critical Imperative for the Reform of British Interpretation of Fetal Heart Rate Decelerations: Analysis of FIGO and NICE Guidelines, Post-Truth Foundations, Cognitive Fallacies, Myths and Occam's Razor. J Clin Med Res 2017; 9:253-265. [PMID: 28270884 PMCID: PMC5330767 DOI: 10.14740/jocmr2877e] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/23/2017] [Indexed: 12/23/2022] Open
Abstract
Cardiotocography (CTG) has disappointingly failed to show good predictability for fetal acidemia or neonatal outcomes in several large studies. A complete rethink of CTG interpretation will not be out of place. Fetal heart rate (FHR) decelerations are the most common deviations, benign as well as manifestation of impending fetal hypoxemia/acidemia, much more commonly than FHR baseline or variability. Their specific nomenclature is important (center-stage) because it provides the basic concepts and framework on which the complex "pattern recognition" of CTG interpretation by clinicians depends. Unfortunately, the discrimination of FHR decelerations seems to be muddled since the British obstetrics adopted the concept of vast majority of FHR decelerations being "variable" (cord-compression). With proliferation of confusing waveform criteria, "atypical variables" became the commonest cause of suspicious/pathological CTG. However, National Institute for Health and Care Excellence (NICE) (2014) had to disband the "typical" and "atypical" terminology because of flawed classifying criteria. This analytical review makes a strong case that there are major and fundamental framing and confirmation fallacies (not just biases) in interpretation of FHR decelerations by NICE (2014) and International Federation of Gynecology and Obstetrics (FIGO) (2015), probably the biggest in modern medicine. This "post-truth" approach is incompatible with scientific practice. Moreover, it amounts to setting oneself for failure. The inertia to change could be best described as "backfire effect". There is abundant evidence that head-compression (and other non-hypoxic mediators) causes rapid rather than shallow/gradual decelerations. Currently, the vast majority of decelerations are attributed to unproven cord compression underpinned by flawed disproven pathophysiological hypotheses. Their further discrimination based on abstract, random, trial and error criteria remains unresolved suggesting a false premise to begin with. This is not surprising considering that the commonest pathophysiology of intrapartum hypoxemia is contraction-induced reduction in uteroplacental perfusion (sometimes already compromised) and not cord compression at all. This distorted categorization causes confusion, false-alarm fatigue and difficulty in focusing on real pathological decelerations making CTG interpretation dysfunctional ultimately compromising patient safety. Obstetricians/midwives should demand reverting to the previous more scientific British categorization of decelerations based solely on time relationship to contractions as advocated by the pioneers like Hon and Caldeyro-Barcia, rather than accepting the current "post-truth" scenario.
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Affiliation(s)
- Shashikant L Sholapurkar
- Department of Obstetrics and Gynaecology, Royal United Hospital Bath NHS Foundation Trust, Combe Park, Bath, BA1 3NG, UK.
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Vejux N, Ledu R, D’ercole C, Piechon L, Loundou A, Bretelle F. Guideline choice for CTG analysis influences first caesarean decision. J Matern Fetal Neonatal Med 2016; 30:1816-1819. [DOI: 10.1080/14767058.2016.1228050] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Nadege Vejux
- Department of Gynaecology and Obstetrics, GYNEPOLE, Hôpital Nord, Assistance Publique-Hôpitaux de Marseille, Aix Marseille Université, AMU, Marseille, France,
| | - Renaud Ledu
- Department of Gynaecology and Obstetrics, GYNEPOLE, Hôpital Nord, Assistance Publique-Hôpitaux de Marseille, Aix Marseille Université, AMU, Marseille, France,
| | - Claude D’ercole
- Department of Gynaecology and Obstetrics, GYNEPOLE, Hôpital Nord, Assistance Publique-Hôpitaux de Marseille, Aix Marseille Université, AMU, Marseille, France,
- Department of Public Health, Assistance Publique-Hôpitaux de Marseille, Aix Marseille Université, AMU, Marseille, France, and
| | - Laurence Piechon
- Department of Gynaecology and Obstetrics, GYNEPOLE, Hôpital Nord, Assistance Publique-Hôpitaux de Marseille, Aix Marseille Université, AMU, Marseille, France,
| | - Anderson Loundou
- Department of Public Health, Assistance Publique-Hôpitaux de Marseille, Aix Marseille Université, AMU, Marseille, France, and
| | - Florence Bretelle
- Department of Gynaecology and Obstetrics, GYNEPOLE, Hôpital Nord, Assistance Publique-Hôpitaux de Marseille, Aix Marseille Université, AMU, Marseille, France,
- Faculté de Médecine de Marseille, UMR CNRS-IRD 6236, Université de la Méditerranée, Marseille, France
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Lear CA, Galinsky R, Wassink G, Yamaguchi K, Davidson JO, Westgate JA, Bennet L, Gunn AJ. The myths and physiology surrounding intrapartum decelerations: the critical role of the peripheral chemoreflex. J Physiol 2016; 594:4711-25. [PMID: 27328617 DOI: 10.1113/jp271205] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2015] [Accepted: 02/17/2016] [Indexed: 11/08/2022] Open
Abstract
A distinctive pattern of recurrent rapid falls in fetal heart rate, called decelerations, are commonly associated with uterine contractions during labour. These brief decelerations are mediated by vagal activation. The reflex triggering this vagal response has been variably attributed to a mechanoreceptor response to fetal head compression, to baroreflex activation following increased blood pressure during umbilical cord compression, and/or a Bezold-Jarisch reflex response to reduced venous return from the placenta. Although these complex explanations are still widespread today, there is no consistent evidence that they are common during labour. Instead, the only mechanism that has been systematically investigated, proven to be reliably active during labour and, crucially, capable of producing rapid decelerations is the peripheral chemoreflex. The peripheral chemoreflex is triggered by transient periods of asphyxia that are a normal phenomenon associated with all uterine contractions. This should not cause concern as the healthy fetus has a remarkable ability to adapt to these repeated but short periods of asphyxia. This means that the healthy fetus is typically not at risk of hypotension and injury during uncomplicated labour even during repeated brief decelerations. The physiologically incorrect theories surrounding decelerations that ignore the natural occurrence of repeated asphyxia probably gained widespread support to help explain why many babies are born healthy despite repeated decelerations during labour. We propose that a unified and physiological understanding of intrapartum decelerations that accepts the true nature of labour is critical to improve interpretation of intrapartum fetal heart rate patterns.
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Affiliation(s)
- Christopher A Lear
- The Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Robert Galinsky
- The Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Guido Wassink
- The Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Kyohei Yamaguchi
- The Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand.,Department of Obstetrics and Gynaecology, Mie University Graduate School of Medicine, Mie, Japan
| | - Joanne O Davidson
- The Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Jenny A Westgate
- The Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand.,Department of Obstetrics and Gynaecology, The University of Auckland, Auckland, New Zealand
| | - Laura Bennet
- The Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - Alistair J Gunn
- The Fetal Physiology and Neuroscience Group, Department of Physiology, The University of Auckland, Auckland, New Zealand.,Starship Children's Hospital, Auckland, New Zealand
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Sholapurkar SL. Imperative for improvements and international convergence of intrapartum fetal monitoring: A bird’s eye view. World J Obstet Gynecol 2016; 5:102-109. [DOI: 10.5317/wjog.v5.i1.102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Revised: 10/25/2015] [Accepted: 11/25/2015] [Indexed: 02/05/2023] Open
Abstract
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 significant improvement in intrapartum fetal monitoring. There seems a need for significant reform. International congruence on most aspects of CTG interpretation [definitions 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 redefining 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 scientific and physiological classification (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 difficult and resource-intensive.
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Sholapurkar SL. Categorization of Fetal Heart Rate Decelerations in American and European Practice: Importance and Imperative of Avoiding Framing and Confirmation Biases. J Clin Med Res 2015; 7:672-80. [PMID: 26251680 PMCID: PMC4522983 DOI: 10.14740/jocmr2166w] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/29/2015] [Indexed: 12/04/2022] Open
Abstract
Interpretation of electronic fetal monitoring (EFM) remains controversial and unsatisfactory. Fetal heart rate (FHR) decelerations are the commonest aberrant feature on cardiotocographs and considered “center-stage” in the interpretation of EFM. A recent American study suggested that the lack of correlation of American three-tier system to neonatal acidemia may be due to the current peculiar nomenclature of FHR decelerations leading to loss of meaning. The pioneers like Hon and Caldeyro-Barcia classified decelerations based primarily on time relationship to contractions and not on etiology per se. This critical analysis debates pros and cons of significant anchoring/framing and confirmation biases in defining different types of decelerations based primarily on the shape (slope) or time of descent. It would be important to identify benign early decelerations correctly to avoid unnecessary intervention as well as to improve the positive predictive value of the other types of decelerations. Currently the vast majority of decelerations are classed as “variable”. This review shows that the most common rapid decelerations during contractions with trough corresponding to peak of contraction cannot be explained by “cord-compression” hypothesis but by direct/pure (defined here as not mediated through baro-/chemoreceptors) or non-hypoxic vagal reflex. These decelerations are benign, most likely and mainly a result of head-compression and hence should be called “early” rather than “variable”. Standardization is important but should be appropriate and withstand scientific scrutiny. Significant framing and confirmation biases are necessarily unscientific and the succeeding three-tier interpretation systems and structures embodying these biases would be dysfunctional and clinically unhelpful. Clinical/pathophysiological analysis and avoidance of flaws/biases suggest that a more physiological and scientific categorization of decelerations should be based on time relationship to contractions alone irrespective of shape or descent time as indeed proposed by pioneers like Hon and Caldeyro-Barcia. Such meaningful categorization, apart from being a scientific necessity, could improve the practical performance of three-tier FHR interpretation systems and possibly application of dependent complementary techniques like fetal ECG/pulse oximetry/computer-aided analysis, thus facilitating future progress in the field of intrapartum fetal monitoring.
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Schifrin BS, Soliman M, Koos B. Litigation related to intrapartum fetal surveillance. Best Pract Res Clin Obstet Gynaecol 2015; 30:87-97. [PMID: 26227999 DOI: 10.1016/j.bpobgyn.2015.06.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 06/30/2015] [Indexed: 10/23/2022]
Abstract
The role of intrapartum care including cardiotocography (CTG) monitoring in cases of perinatal neurological injury receives considerable debate in both clinical and medicolegal settings. The debate, however, has distracted attention from fundamental questions about the timing, mechanism, and preventability of perinatal injury. CTG tracings are used as a surrogate for asphyxia with the timing of intervention ("rescue") predicated on the presumed severity of asphyxia. Using CTG in this way has prevented intrapartum stillbirth, but it has not reduced the long-term injury in part, because, contrary to popular belief, the majority of intrapartum fetal injuries are unassociated with severe hypoxia or severe neonatal depression. This article describes the timing and mechanisms, including mechanical factors, of intrapartum perinatal injury and the benefit of using the CTG, not for the purpose of "rescue", but for identifying risk factors for fetal injury and keeping the fetus out of harm's way.
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Affiliation(s)
- Barry S Schifrin
- Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
| | - Mohamed Soliman
- Department of Obstetrics and Gynecology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Brian Koos
- Department of Obstetrics and Gynecology, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
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Sholapurkar SL. Re: Are we (mis)guided by current guidelines on intrapartum fetal heart rate monitoring? Case for a more physiological approach to interpretation. BJOG 2015; 122:589-90. [PMID: 25702551 DOI: 10.1111/1471-0528.13174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/05/2014] [Indexed: 11/28/2022]
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Sholapurkar SL. Algorithm for management of category II fetal heart rate tracings: a standardization of right sort? Am J Obstet Gynecol 2014; 210:175. [PMID: 23999416 DOI: 10.1016/j.ajog.2013.08.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 08/28/2013] [Indexed: 12/23/2022]
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Sholapurkar SL. Critical evaluation of American categorization of fetal heart rate (FHR) decelerations and three tier classification—Shortcomings, contradictions, remedies and need for debate. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/ojog.2013.33067] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Sholapurkar SL. Interpretation of British experts’ illustrations of fetal heart rate (FHR) decelerations by Consultant Obstetricians, registrars and midwives: A prospective study—Reasons for major disagreement with experts and implications for clinical practice. ACTA ACUST UNITED AC 2013. [DOI: 10.4236/ojog.2013.36085] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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