Viability and thresholds for treatment of extremely preterm infants: survey of UK neonatal professionals

Supporting Antenatal Counselling for Anticipated Preterm Births at the Limits of Viability in Non-Tertiary Centres

Background: Presentations of preterm labour at <25 weeks of gestational age (GA) require timely evidence-based counselling and management to optimise outcomes and facilitate informed decisions. In non-tertiary centres, this counselling is often especially challenging. Objectives: (1) To develop a tool to support counselling for preterm births at <25 weeks of GA, and (2) to refine and facilitate the utilisation of this tool and develop targeted supports through an understanding of challenges to providing counselling in non-tertiary centres. Methods: Perinatal risk factors and local outcome data were incorporated into a counselling tool. Semi-structured virtual interviews were conducted with participants with experience in counselling or receiving care at <25 weeks of GA in non-tertiary centres. Interviewees included transport team members, paediatricians, obstetricians, one family physician, and one parent. Analysis using interpretive description methodology was performed to identify themes in participant practice and experience. Results: A risk-based counselling tool was developed, including guidance for counselling discussions. Twenty-one interviews were completed. Practice challenges that were identified included a lack of updated knowledge on practices in tertiary centres, discomfort in providing counselling, variability in counselling content, and a variation in health care provider teams involved in counselling. All providers expressed a desire for further education in this area. Conclusions: Support for providers in non-tertiary centres in the counselling of periviable preterm families is much needed. The development of our practice tool targeted for non-tertiary centres provides an important step in this process. The next steps include responding to the expressed need from providers for education and training in the counselling and management of periviable preterm pregnancies.

Decision threshold models in medical decision making: a scoping literature review

BACKGROUND

Decision thresholds play important role in medical decision-making. Individual decision-making differences may be attributable to differences in subjective judgments or cognitive processes that are captured through the decision thresholds. This systematic scoping review sought to characterize the literature on non-expected utility decision thresholds in medical decision-making by identifying commonly used theoretical paradigms and contextual and subjective factors that inform decision thresholds.

METHODS

A structured search designed around three concepts-individual decision-maker, decision threshold, and medical decision-was conducted in MEDLINE (Ovid) and Scopus databases from inception to July 2023. ProQuest (Dissertations and Theses) database was searched to August 2023. The protocol, developed a priori, was registered on Open Science Framework and PRISMA-ScR guidelines were followed for reporting on this study. Titles and abstracts of 1,618 articles and the full texts for the 228 included articles were reviewed by two independent reviewers. 95 articles were included in the analysis. A single reviewer used a pilot-tested data collection tool to extract study and author characteristics, article type, objectives, theoretical paradigm, contextual or subjective factors, decision-maker, and type of medical decision.

RESULTS

Of the 95 included articles, 68 identified a theoretical paradigm in their approach to decision thresholds. The most common paradigms included regret theory, hybrid theory, and dual processing theory. Contextual and subjective factors that influence decision thresholds were identified in 44 articles.

CONCLUSIONS

Our scoping review is the first to systematically characterizes the available literature on decision thresholds within medical decision-making. This study offers an important characterization of the literature through the identification of the theoretical paradigms for non-expected utility decision thresholds. Moreover, this study provides insight into the various contextual and subjective factors that have been documented within the literature to influence decision thresholds, as well as these factors juxtapose theoretical paradigms.

Variability of Care Practices for Extremely Early Deliveries

OBJECTIVES

Assess temporal changes, intercenter variability, and birthing person (BP) factors relating to interventions for extremely early deliveries.

METHODS

Retrospective study of BPs and newborns delivered from 22-24 completed weeks at 13 US centers from 2011-2020. Rates of neonatology consultation, antenatal corticosteroids, cesarean delivery, live birth, attempted resuscitation (AR), and survival were assessed by epoch, center, and gestational age.

RESULTS

2028 BPs delivering 2327 newborns were included. Rates increased in epoch 2-at 22 weeks: neonatology consultation (37.6 vs 64.3%, P < .001), corticosteroids (11.4 vs 29.5%, P < .001), live birth (66.2 vs 78.6%, P < .001), AR (20.1 vs 36.9%, P < .001), overall survival (3.0 vs 8.9%, P = .005); and at 23 weeks: neonatology consultation (73.0 vs 80.5%, P = .02), corticosteroids (63.7 vs 83.7%, P < .001), cesarean delivery (28.0 vs 44.7%, P < .001), live birth (88.1 vs 95.1%, P < .001), AR (67.7 vs 85.2%, P < .001), survival (28.8 vs 41.6%, P < .001). Over time, intercenter variability increased at 22 weeks for corticosteroids (interquartile range 18.0 vs 42.0, P = .014) and decreased at 23 for neonatology consultation (interquartile range 23.0 vs 5.2, P = .045). In BP-level multivariate analysis, AR was associated with increasing gestational age and birth weight, Black BP race, previous premature delivery, and delivery center.

CONCLUSIONS

Intervention rates for extremely early newborns increased and intercenter variability changed over time. In BP-level analysis, factors significantly associated with AR included Black BP race, previous premature delivery, and center.

Withdrawal and withholding of life sustaining treatment (WWLST): an under recognised factor in the morbidity or mortality of periviable infants?-a narrative review

Background and Objective

The morbidity and mortality of infants born extremely preterm varies substantially across networks, within countries and throughout the globe. Most of the literature tends to focus on the management at birth and choices around active resuscitation of extremely preterm infants. Withdrawal and withholding of life sustaining treatment (WWLST) is an important and central process in the neonatal intensive care unit (NICU) and practices vary substantially. As such, our objective in this review was to explore whether end of life decisions also contribute to variations in the morbidity and mortality of periviable infants.

Methods

This narrative literature review is based on studies from the last 15 years found using several searches of medical databases (OVID Medline, Scopus and Cochrane Systematic Reviews) performed between March 2021 and December 2023.

Key Content and Findings

Just as outcomes in periviable infants vary, the rates of and processes behind WWLST differ in the periviable population. Variation increases as gestational age decreases. Parental involvement is crucial to share decision making but the circumstances and rates of parental involvement differ. Strict guidelines in end-of-life care may not be appropriate, however there is a need for more targeted guidance for periviable infants as a specific population. The current literature available relating to periviable infants or WWLST is minimal, with many datasets rapidly becoming outdated.

Conclusions

Further research is needed to establish the role of WWLST in variation of periviable infants' outcomes. The unification of data, acquisition of more recent datasets and inclusion of variables relating to end-of-life decisions in data collection will aid in this process.

Differences in the attitudes towards resuscitation of extremely premature infants between neonatologists and obstetricians: a survey study in China

Objectives

Neonatologists and obstetricians are crucial decision-makers regarding the resuscitation of extremely preterm infants (EPIs). However, there is a scarcity of research regarding the differing perspectives on EPI resuscitation between these medical professionals. We aim to determine the differences and influential factors of their attitudes towards EPIs resuscitation in China.

Methods

This cross-sectional study was conducted in public hospitals of 31 provinces in Chinese mainland from June to July 2021. Influential factors of binary variables and those of ordinal variables were analyzed by modified Poisson regression models and multinomial logistic regression models due to the invalid parallel line assumption of ordinal logistic regression models.

Results

A total of 832 neonatologists and 1,478 obstetricians who were deputy chief physicians or chief physicians participated. Compared with obstetricians, neonatologists delivered a larger proportion of infants of <28-week gestational age (87.74% vs. 84.91%) and were inclined to think it inappropriate to use 28 weeks as the cutoff of gestational age for providing full care to premature infants [63.34% vs. 31.60%, adjusted prevalence ratio = 1.61 (95% CI: 1.46-1.77)], and to suggest smaller cutoffs of gestational age and birth weight for providing EPIs resuscitation. Notably, 46.49% of the neonatologists and 19.01% of the obstetricians believed infants ≤24 weeks' gestation should receive resuscitation.

Conclusions

In China, notable disparities exist in attitudes of neonatologists and obstetricians towards resuscitating EPIs. Strengthening collaboration between these two groups and revising the pertinent guidelines as soon as possible would be instrumental in elevating the resuscitation rate of EPIs.

Characterizing post-branching nephrogenesis in the neonatal rabbit

Human nephrogenesis ends prior to birth in term infants (34-36 week gestation), with most (60%) nephrons forming in late gestation in two post-branching nephrogenesis (PBN) periods: arcading and lateral branch nephrogenesis. Preterm infants, however, must execute PBN postnatally. Extreme prematurity is associated with low nephron counts. Identifying additional model(s) that undergo PBN postnatally will help support postnatal PBN in preterm infants. The rabbit exhibits longer postnatal nephrogenesis than the mouse but whether it forms nephrons through PBN has not been determined. We performed morphologic and immunohistological assessments of rabbit nephrogenesis from birth (post-conceptual day 31 or 32) to PC49 using H&E and antibodies against SIX1, SIX2, WT1, ZO-1, and JAG1 in the postnatal period. We performed 3D rendering of the nephrogenic niche to assess for PBN, and supplemented the staining with RNAScope to map the expression of Six1, Six2 (nephron progenitors, NPC), and Ret (ureteric bud tip) transcripts to determine the nephrogenic niche postnatal lifespan. Unlike the mouse, rabbit SIX2 disappeared from NPC before SIX1, resembling the human niche. Active nephrogenesis as defined by the presence of SIX1 + naïve NPC/tip population persisted only until PC35-36 (3-5 postnatal days). 3D morphologic assessments of the cortical nephrons identified an elongated tubule with attached glomeruli extending below the UB tip, consistent with PBN arcades, but not with lateral branch nephrogenesis. We conclude that the rabbit shows morphologic and molecular evidence of PBN arcades continuing postnatally for a shorter period than previously thought. The rabbit is the first non-primate expressing SIX1 in the progenitor population. Our findings suggest that studies of arcading in postnatal nephrogenic niche should be performed within the first 5 days of life in the rabbit.

Artificial placenta technology: History, potential and perception

As presently conceptualised, the artificial placenta (AP) is an experimental life support platform for extremely preterm infants (i.e. 400-600 g; 21-23+6 weeks of gestation) born at the border of viability. It is based around the oxygenation of the periviable fetus using gas-exchangers connected to the fetal vasculature. In this system, the lung remains fluid-filled and the fetus remains in a quiescent state. The AP has been in development for some sixty years. Over this time, animal experimental models have evolved iteratively from employing external pump-driven systems used to support comparatively mature fetuses (generally goats or sheep) to platforms driven by the fetal heart and used successfully to maintain extremely premature fetuses weighing around 600 g. Simultaneously, sizable advances in neonatal and obstetric care mean that the nature of a potential candidate patient for this therapy, and thus the threshold success level for justifying its adoption, have both changed markedly since this approach was first conceived. Five landmark breakthroughs have occurred over the developmental history of the AP: i) the first human studies reported in the 1950's; ii) foundation animal studies reported in the 1960's; iii) the first extended use of AP technology combined with fetal pulmonary resuscitation reported in the 1990s; iv) the development of AP systems powered by the fetal heart reported in the 2000's; and v) the adaption of this technology to maintain extremely preterm fetuses (i.e. 500-600 g body weight) reported in the 2010's. Using this framework, the present paper will provide a review of the developmental history of this long-running experimental system and up-to-date assessment of the published field today. With the apparent acceleration of AP technology towards clinical application, there has been an increase in the attention paid to the field, along with some inaccurate commentary regarding its potential application and merits. Additionally, this paper will address several misrepresentations regarding the potential application of AP technology that serve to distract from the significant potential of this approach to greatly improve outcomes for extremely preterm infants born at or close to the present border of viability.

Ethics Considerations Regarding Artificial Womb Technology for the Fetonate

Since the early 1980's, with the clinical advent of in vitro fertilization resulting in so-called "test tube babies," a wide array of ethical considerations and concerns regarding artificial womb technology (AWT) have been described. Recent breakthroughs in the development of extracorporeal neonatal life support by means of AWT have reinitiated ethical interest about this topic with a sense of urgency. Most of the recent ethical literature on the topic, however, pertains not to the more imminent scenario of a physiologically improved method of neonatal care through AWT, but instead to the remote scenario of "complete ectogenesis" that imagines human gestation occurring entirely outside of the womb. This scoping review of the ethical literature on AWT spans from more abstract concerns about complete ectogenesis to more immediate concerns about the soon-to-be-expected clinical life support of what we term the fetal neonate or fetonate. Within an organizing framework of different stages of human gestational development, from conception to the viable premature infant, we discuss both already identified and newly emerging ethical considerations and concerns regarding AWT and the care of the fetonate.

Ethical Dilemmas in Neonatal Care at the Limit of Viability

Advances in neonatal care have pushed the limit of viability to incrementally lower gestations over the last decades. However, surviving extremely premature neonates are prone to long-term neurodevelopmental handicaps. This makes ethics a crucial dimension of periviable birth management. At 22 weeks, survival ranges from 1 to 15%, and profound disabilities in survivors are common. Consequently, there is no beneficence-based obligation to offer any aggressive perinatal management. At 23 weeks, survival ranges from 8 to 54%, and survival without severe handicap ranges from 7 to 23%. If fetal indication for cesarean delivery appears, the procedure may be offered when neonatal resuscitation is planned. At a gestational age ≥24 weeks, up to 51% neonates are expected to survive the neonatal period. Survival without profound neurologic disability ranges from 12 to 38%. Beneficence-based obligation to intervene is reasonable at these gestations. Nevertheless, autonomy of parents should also be respected, and parental consent should be sought prior to any intervention. Optimal counselling of parents involves harmonized cooperation of obstetric and neonatal care providers. Every fetus/neonate and every pregnant woman are different and have the right to be considered individually when treatment decisions are being made.

Prognosis, counseling, and indications for termination of pregnancy

As the coincidence of pregnancy and cancer rise, clinicians must be prepared to counsel their patients on the complex relationship between maternal and fetal health. In most types of cancer, maternal prognosis mirrors that of non-pregnant women. However, challenges associated with the timing of diagnosis and treatment can present additional risks. Consequently, pregnant cancer patients must be counseled early and effectively with regard to how their pregnancy status affects treatment options and the range of expected outcomes for both mother and fetus. Some patients choose to terminate pregnancy after such counseling, though the specific course of action depends on the cancer in question, the stage at diagnosis, and the personal priorities and values of the patient.

Assessing risks at 22-24 weeks gestation

The recent British Association of Perinatal Medicine (BAPM) guidance published in 2019 suggested for the first time that we can consider resuscitation of extremely premature infants (EPI) at 22-24 weeks gestational age (GA) on a case-by-case basis in the UK. This has sent waves throughout UK neonatal units, and we believe this arises because we're now confronted with challenging decisions about whether a foetus under 24 weeks will be viable or not, and whether it's in their best interests to provide 'survival-focused' care (SFC) or 'comfort-focused' care (CFC). Despite a robust framework introduced by BAPM, we believe uncertainty still remains.

Attitudes About Extremely Preterm Birth Among Obstetric and Neonatal Health Care Professionals in England: A Qualitative Study

Importance

Variation in attitudes between health care professionals involved in the counseling of parents facing extremely preterm birth (<24 wk gestational age) may lead to parental confusion and professional misalignment.

Objective

To explore the attitudes of health care professionals involved in the counseling of parents facing preterm birth on the treatment of extremely preterm infants.

Design, Setting, and Participants

This qualitative study used Q methods to explore the attitudes of neonatal nurses, neonatologists, midwives, and obstetricians involved in the care of extremely preterm infants in 4 UK National Health Service perinatal centers between February 10, 2020, and April 30, 2021. Each participating center had a tertiary level neonatal unit and maternity center. Individuals volunteered participation through choosing to complete the study following a presentation by researchers at each center. A link to the online Q study was emailed to all potential participants by local principal investigators. Participants ranked 53 statements about the treatment of extremely preterm infants in an online quasi-normal distribution grid from strongly agree (6) to strongly disagree (-6).

Main Outcomes and Measures

Distinguishing factors per professional group (representing different attitudes) identified through by-person factor analysis of Q sort-data were the primary outcome. Areas of shared agreement (consensus) between professional groups were also explored. Q sorts achieving a factor loading of greater than 0.46 (P < .01) on a given factor were included.

Results

In total, 155 health care professionals volunteered participation (128 [82.6%] women; mean [SD] age, 41.6 [10.2] years, mean [SD] experience, 14.1 [9.6] years). Four distinguishing factors were identified between neonatal nurses, 3 for midwives, 5 for neonatologists, and 4 for obstetricians. Analysis of factors within and between professional groups highlighted significant variation in attitudes of professionals toward parental engagement in decision-making, the perceived importance of potential disability in decision-making, and the use of medical technology. Areas of consensus highlighted that most professionals disagreed with statements suggesting disability equates to reduced quality of life. The statement suggesting the parents' decision was considered the most important when considering neonatal resuscitation was placed in the neutral (middistribution) position by all professionals.

Conclusions and Relevance

The findings of this qualitative study suggest that parental counseling at extremely low gestations is a complex scenario further complicated by the differences in attitudes within and between professional disciplines toward treatment approaches. The development of multidisciplinary training encompassing all professional groups may facilitate a more consistent and individualized approach toward parental engagement in decision-making.

Individualised decision making: interpretation of risk for extremely preterm infants-a survey of UK neonatal professionals

BACKGROUND

The British Association of Perinatal Medicine (BAPM) published a revised framework for perinatal management of extremely preterm infants (EPIs) in 2019. We aimed to assess UK neonatal professionals' interpretation of elements of this framework, as well as the consistency of their estimates of outcome for EPIs.

METHODS

An online survey gave participants five cases involving anticipated extremely preterm birth with different favourable and unfavourable risk factors. Respondents were asked to assign a risk category and management option using the BAPM framework and to estimate the chance of survival if the baby received active resuscitation and the chance of severe disability if they survived.

RESULTS

Respondents were consistent in interpretation of risk categories. The majority would follow parental wishes about management. Management decisions did not always correspond with risk assessment, with less inclination to recommend palliative (comfort) care. There were wide estimates of survival or severe disability (5%-90%) with consultants providing lower estimates of severe disability than other groups.

CONCLUSION

UK neonatal professionals deferred to parental wishes in the cases presented, indicating an emphasis on shared decision making. However, they did not necessarily use the risk stratification approach for management decisions. Variation in estimates of outcome raises questions about the accuracy of informed decision making and suggests support is needed for UK clinicians to incorporate risk factors into individualised counselling. There may be value in validating existing online risk calculators for UK infants or in developing a UK specific risk model.

Perinatal care for the extremely preterm infant

Being born preterm (prior to 37 weeks of completed gestation) is a leading cause of childhood death up to five years of age, and is responsible for the demise of around one million preterm infants each year. Rates of prematurity, which range from approximately 5 to 18% of births, are increasing in most countries. Babies born extremely preterm (less than 28 weeks' gestation) and in particular, in the periviable (20^0/7-25^6/7 weeks) period, are at the highest risk of death, or the development of long-term disabilities. The perinatal care of extremely preterm infants and their mothers raises a number of clinical, technical, and ethical challenges. Focusing on 'micropremmies', or those born in the periviable period, this paper provides an update regarding the aetiology and impacts of periviable preterm birth, advances in the antenatal, intrapartum, and acute post-natal management of these infants, and a review of counselling/support approaches for engaging with the infant's family. It concludes with an overview of emerging technology that may assist in improving outcomes for this at-risk population.

Elternzentrierte ethische Entscheidungsfindung für Frühgeborene im Grenzbereich der Lebensfähigkeit – Reflexion über die Bedeutung probabilistischer Prognosen als Entscheidungsgrundlage

Frühgeborene im Grenzbereich der Lebensfähigkeit befinden sich in einer prognostischen Grauzone. Das bedeutet, dass deren Prognose zwar schlecht, aber nicht hoffnungslos ist, woraus folgt, dass nach Geburt lebenserhaltende Behandlungen nicht obligatorisch sind. Die Entscheidung für oder gegen lebenserhaltende Maßnahmen ist wertbeladen und für alle Beteiligten enorm herausfordernd. Sie sollte eine zwischen Eltern und Ärzt*innen geteilte Entscheidung sein, wobei sie unbedingt mit den Präferenzen der Eltern abgestimmt sein sollte. Bei der pränatalen Beratung der Eltern legen die behandelnden Ärzt*innen üblicherweise numerische Schätzungen der Prognose vor und nehmen in der Regel an, dass die Eltern ihre Behandlungspräferenzen davon ableiten. Inwieweit probabilistische Daten die Entscheidungen der Eltern in prognostischen Grauzonen tatsächlich beeinflussen, ist noch unzureichend untersucht. In der hier vorliegenden Arbeit wird eine Studie reflektiert, in welcher die Hypothese geprüft wurde, dass numerisch bessere oder schlechtere kindliche Prognosen die Präferenzen werdender Mütter für lebenserhaltende Maßnahmen nicht beeinflussen. In dieser Studie zeigte sich, dass die elterlichen Behandlungspräferenzen eher von individuellen Einstellungen und Werten als von Überlegungen zu numerischen Ergebnisschätzungen herzurühren scheinen. Unser Verständnis, welche Informationen werdende Eltern, die mit einer extremen Frühgeburt konfrontiert sind, wünschen und brauchen, ist noch immer unvollständig. Bedeutende medizinische Entscheidungen werden keineswegs nur rational und prognoseorientiert gefällt. In der vorliegenden Arbeit wird diskutiert, welchen Einfluss der Prozess der Entscheidungsfindung auf das Beratungsergebnis haben kann und welche Implikationen sich aus den bisher vorliegenden Studienergebnissen ergeben – klinisch-praktisch, ethisch und wissenschaftlich.

Gestation-Based Viability-Difficult Decisions with Far-Reaching Consequences

Most clinicians rely on outcome data based on completed weeks of gestational of fetal maturity for antenatal and postnatal counseling, especially for preterm infants born at the margins of viability. Contemporary estimation of gestational maturity, based on ultrasounds, relies on the use of first-trimester scans, which offer an accuracy of ±3-7 days, and depend on the timing of the scans and the measurements used in the calculations. Most published literature on the outcomes of babies born prematurely have reported on short- and long-term outcomes based on completed gestational weeks of fetal maturity at birth. These outcome data change significantly from one week to the next, especially around the margin of gestational viability. With a change in approach solely from decisions based on survival, to disability-free survival and long-term functional outcomes, the complexity of the parental and care provider's decision-making in the perinatal and postnatal period for babies born at less than 25 weeks gestation remains challenging. While sustaining life following birth at the margins of viability remains our priority-identifying and mitigating risks associated with extremely preterm birth begins in the perinatal period. The challenge of supporting the normal maturation of these babies postnatally has far-reaching consequences and depends on our ability to sustain life while optimizing growth, nutrition, and the repair of organs compromised by the consequences of preterm birth. This article aims to explore the ethical and medical complexities of contemporary decision-making in the perinatal and postnatal periods. We identify gaps in our current knowledge of this topic and suggest areas for future research, while offering a perspective for future collaborative decision-making and care for babies born at the margins of viability.