Outcomes of preterm infants following the introduction of room air resuscitation

The Respiratory Management of the Extreme Preterm in the Delivery Room

The fetal-to-neonatal transition poses an extraordinary challenge for extremely low birth weight (ELBW) infants, and postnatal stabilization in the delivery room (DR) remains challenging. The initiation of air respiration and the establishment of a functional residual capacity are essential and often require ventilatory support and oxygen supplementation. In recent years, there has been a tendency towards the soft-landing strategy and, subsequently, non-invasive positive pressure ventilation has been generally recommended by international guidelines as the first option for stabilizing ELBW in the delivery room. On the other hand, supplementation with oxygen is another cornerstone of the postnatal stabilization of ELBW infants. To date, the conundrum concerning the optimal initial inspired fraction of oxygen, target saturations in the first golden minutes, and oxygen titration to achieve desired stability saturation and heart rate values has not yet been solved. Moreover, the retardation of cord clamping together with the initiation of ventilation with the patent cord (physiologic-based cord clamping) have added additional complexity to this puzzle. In the present review, we critically address these relevant topics related to fetal-to-neonatal transitional respiratory physiology, ventilatory stabilization, and oxygenation of ELBW infants in the delivery room based on current evidence and the most recent guidelines for newborn stabilization.

EFFICACY OF PRIMARY REHABILITATION MEASURES ASSOCIATED WITH THE DEVELOPMENT OF RECURRENT BRONCHIAL OBSTRUCTION SYNDROME IN YOUNG CHILDREN WITH RESPIRATORY DISORDERS IN NEONATAL PERIOD

OBJECTIVE

The aim: To improve primary prophylactic measures associated with the development and progression of recurrent bronchial obstruction syndrome in young children, who had suffered respiratory disorders in neonatal period.

PATIENTS AND METHODS

Materials and methods: Algorithm of primary prophylactic measures implied adequate balanced nutrition, sanation of living conditions, restriction of contact with infectious agents, sanation of chronic foci of infection, systematic training and general fitness. The investigation included 160 young children (1 day - 3 years of age). The basic group (n=80) involved children, who had experienced respiratory disorders in neonatal period and received appropriate respiratory therapy (artificial ventilation and / or spontaneous breathing with continuous positive airway pressure and supply of free oxygen), control group - children, who did not have respiratory disorders and respiratory therapy (n=80).

RESULTS

Results: Conducted investigation throughout 12-month monitoring enabled to record the development of recurrent bronchial obstruction syndrome in 43 children (respectively, 30 - 37.50% patients of the basic group versus 13 - 16.25% of control group; p 0.05), could not be obtained.

CONCLUSION

Conclusions: Comparative analysis within groups did not show a reliable difference in the development of recurrent bronchial obstruction syndrome in children (р>0.05), which can be explained by partial following of doctor's recommendations. There is the need in further study of the issue involving more patients for a longer period of monitoring.

Supplemental Oxygen in the Newborn: Historical Perspective and Current Trends

Oxygen is the final electron acceptor in aerobic respiration, and a lack of oxygen can result in bioenergetic failure and cell death. Thus, administration of supplemental concentrations of oxygen to overcome barriers to tissue oxygen delivery (e.g., heart failure, lung disease, ischemia), can rescue dying cells where cellular oxygen content is low. However, the balance of oxygen delivery and oxygen consumption relies on tightly controlled oxygen gradients and compartmentalized redox potential. While therapeutic oxygen delivery can be life-saving, it can disrupt growth and development, impair bioenergetic function, and induce inflammation. Newborns, and premature newborns especially, have features that confer particular susceptibility to hyperoxic injury due to oxidative stress. In this review, we will describe the unique features of newborn redox physiology and antioxidant defenses, the history of therapeutic oxygen use in this population and its role in disease, and clinical trends in the use of therapeutic oxygen and mitigation of neonatal oxidative injury.

Inhaled Nitric Oxide at Birth Reduces Pulmonary Vascular Resistance and Improves Oxygenation in Preterm Lambs

Resuscitation with 21% O₂ may not achieve target oxygenation in preterm infants and in neonates with persistent pulmonary hypertension of the newborn (PPHN). Inhaled nitric oxide (iNO) at birth can reduce pulmonary vascular resistance (PVR) and improve PaO₂. We studied the effect of iNO on oxygenation and changes in PVR in preterm lambs with and without PPHN during resuscitation and stabilization at birth. Preterm lambs with and without PPHN (induced by antenatal ductal ligation) were delivered at 134 d gestation (term is 147–150 d). Lambs without PPHN were ventilated with 21% O₂, titrated O₂ to maintain target oxygenation or 21% O₂ + iNO (20 ppm) at birth for 30 min. Preterm lambs with PPHN were ventilated with 50% O₂, titrated O₂ or 50% O₂ + iNO. Resuscitation with 21% O₂ in preterm lambs and 50%O₂ in PPHN lambs did not achieve target oxygenation. Inhaled NO significantly decreased PVR in all lambs and increased PaO₂ in preterm lambs ventilated with 21% O₂ similar to that achieved by titrated O₂ (41 ± 9% at 30 min). Inhaled NO increased PaO₂ to 45 ± 13, 45 ± 20 and 76 ± 11 mmHg with 50% O₂, titrated O₂ up to 100% and 50% O₂ + iNO, respectively, in PPHN lambs. We concluded that iNO at birth reduces PVR and FiO₂ required to achieve target PaO₂.

Oxygen saturation (SpO2) targeting for newborn infants at delivery: Are we reaching for an impossible unknown?

For more than 200 years, pure oxygen was given ad libitum to newborn infants requiring resuscitation. Due to oxidative stress and injury concerns, a paradigm shift towards using "less" oxygen, including air (21% oxygen) instead of pure (100%) oxygen, occurred about twenty years ago. A decade later, clinicians were advised to adjust fractional inspired oxygen (FiO₂) to target oxygen saturations (SpO₂) that were derived from spontaneously breathing, healthy, mature infants. Whether these recommendations are achievable, beneficial, harmful or redundant is uncertain. The underlying pathology leading to resuscitation varies between infants and may considerably alter an infant's response to supplemental oxygen. In this review, we summarize available evidence for the use of SpO₂ monitoring at delivery for newborn infants, elucidate existing knowledge and service gaps, and suggest future research recommendations that will lead to the safest clinical strategies for this standard and important practice.

Oxygen Therapy for Neonatal Resuscitation in the Delivery Room

Oxygen is commonly used in the delivery room during neonatal resuscitation. The transition from intrauterine to extrauterine life is a challenge to newborns, and exposure to too much oxygen can cause an increase in oxidative stress. The goal of resuscitation is to achieve normal oxygen levels as quickly as possible while avoiding excessive oxygen exposure and preventing inadequate oxygen supplementation. Although it has been shown that room air resuscitation is as effective as using 100% oxygen, often preterm infants need some degree of oxygen supplementation. The ideal concentration of oxygen with which to initiate resuscitation is yet to be determined. Current delivery room resuscitation guidelines recommend the use of room air for term newborns and preterm newborns of greater than or equal to 35 weeks' gestation and the use of a fraction of inspired oxygen of 0.21 to 0.3 for preterm infants of less than 35 weeks' gestation. Further recommendations include titrating oxygen supplementation as needed to obtain goal saturations. However, there is no current consensus on an intermediate oxygen concentration to start resuscitation or goal range saturations for preterm and asphyxiated term infants.

Neonatal oxygen saturations and blood pressure at school-age in children born extremely preterm: a cohort study

OBJECTIVE

To explore the relationship between neonatal oxygen saturation and BP at age 6-7 years in a cohort of infants born extremely preterm.

STUDY DESIGN

Infants <28 weeks gestation were assigned to a higher or lower oxygen saturation target. Oximeter data were monitored throughout the neonatal period. A subset of survivors was seen at age 6. BP was measured and compared by group assignment, achieved saturations, and time spent in hypoxemia (saturations <80%).

RESULTS

There was no difference in systolic or diastolic BP between assigned groups. Median achieved weekly oxygen saturation was not associated with BP. Longer duration of hypoxemia during the first week of age was associated with higher systolic BP.

CONCLUSIONS

Neither target nor actual median oxygen saturations in this study was associated with BP at school age. Increased duration of hypoxemia in the first postnatal week was associated with higher systolic BP at 6-7 years of age.

Optimizing oxygen therapy for preterm infants at birth: Are we there yet?

Premature infants undergo a complex postnatal adaptation at birth. For last two centuries, oxygen has been integral to respiratory support of preterm infants at birth. Excess oxygen can cause oxidative stress and tissue injury. Preterm infants due to lung immaturity may need oxygen for successful transition at birth. Although, considerable progress has been made in the last 3 decades, optimum oxygen therapy for preterm delivery room resuscitation remains unknown. In this review, we discuss the history and physiology behind oxygen therapy in the delivery room, evaluate current literature, provide practice points and point out knowledge gaps of oxygen therapy in preterm infant at birth.

Oxygen therapy in preterm infants with pulmonary hypertension

Premature neonates <34 weeks gestation can present with early-onset, late-onset and bronchopulmonary dysplasia (BPD) associated pulmonary hypertension (PHT), with clinical, echocardiographic, and histological features similar to term infants with PHT. Changes in pulmonary vascular resistance (PVR) in response to oxygen are diminished in preterm infants compared to term. Studies from preterm lambs and human infants with BPD have shown that PaO₂ > 30-55 mm Hg promotes pulmonary vasodilation. Targeting saturations of 80-85% by 5 min, 85-95% by 10 min during resuscitation and 90-95% during the postnatal course are appropriate targets for routine management of preterm infants. Among preterm infants with PHT, avoiding hypoxia/hyperoxia by titrating supplemental oxygen to maintain saturations in low to mid 90s with alarm limits at 90 and 97% seems to be a reasonable approach pending further studies. Further high-quality evidence generated from randomized trials is required to guide oxygen therapy in preterm PHT.

Oxygen Supplementation During Preterm Stabilization and the Relevance of the First 5 min After Birth

Fetal to neonatal transition entails cardiorespiratory, hemodynamic, and metabolic changes coinciding with the switch from placental to airborne respiration with partial pressures of oxygen of 4-5 kPa in utero raising to 8-9 kPa ex utero in few minutes. Preterm infants have immature lung and antioxidant defense system. Very preterm infants (<32 weeks' gestation) frequently require positive pressure ventilation and oxygen to establish lung aeration, a functional residual capacity, and overcome a tendency toward hypoxemia and bradycardia in the first minutes after birth. Recent studies have shown that prolonged bradycardia (heart rate <100 beats per minute) and/or hypoxemia (oxygen saturation <80%) are associated with increased mortality and/or intracranial hemorrhage. However, despite the accumulated evidence, the way in which oxygen should be supplemented in the first minutes after birth still has not yet been clearly established. The initial inspired fraction of oxygen and its adjustment within a safe arterial oxygen saturation range measured by pulse oximetry that avoids hyper-or-hypoxia is still a matter of debate. Herewith, we present a current summary aiming to assist the practical neonatologist who has to aerate the lung and establish an efficacious respiration in very preterm infants in the delivery room.

2019 American Heart Association Focused Update on Neonatal Resuscitation: An Update to the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care

This 2019 focused update to the American Heart Association neonatal resuscitation guidelines is based on 2 evidence reviews recently completed under the direction of the International Liaison Committee on Resuscitation Neonatal Life Support Task Force. The International Liaison Committee on Resuscitation Expert Systematic Reviewer and content experts performed comprehensive reviews of the scientific literature on the appropriate initial oxygen concentration for use during neonatal resuscitation in 2 groups: term and late-preterm newborns (≥35 weeks of gestation) and preterm newborns (<35 weeks of gestation). This article summarizes those evidence reviews and presents recommendations. The recommendations for neonatal resuscitation are as follows: In term and late-preterm newborns (≥35 weeks of gestation) receiving respiratory support at birth, the initial use of 21% oxygen is reasonable. One hundred percent oxygen should not be used to initiate resuscitation because it is associated with excess mortality. In preterm newborns (<35 weeks of gestation) receiving respiratory support at birth, it may be reasonable to begin with 21% to 30% oxygen and to base subsequent oxygen titration on oxygen saturation targets. These guidelines require no change in the Neonatal Resuscitation Algorithm-2015 Update.

2019 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations: Summary From the Basic Life Support; Advanced Life Support; Pediatric Life Support; Neonatal Life Support; Education, Implementation, and Teams; and First Aid Task Forces

The International Liaison Committee on Resuscitation has initiated a continuous review of new, peer-reviewed, published cardiopulmonary resuscitation science. This is the third annual summary of the International Liaison Committee on Resuscitation International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. It addresses the most recent published resuscitation evidence reviewed by International Liaison Committee on Resuscitation Task Force science experts. This summary addresses the role of cardiac arrest centers and dispatcher-assisted cardiopulmonary resuscitation, the role of extracorporeal cardiopulmonary resuscitation in adults and children, vasopressors in adults, advanced airway interventions in adults and children, targeted temperature management in children after cardiac arrest, initial oxygen concentration during resuscitation of newborns, and interventions for presyncope by first aid providers. Members from 6 International Liaison Committee on Resuscitation task forces have assessed, discussed, and debated the certainty of the evidence on the basis of the Grading of Recommendations, Assessment, Development, and Evaluation criteria, and their statements include consensus treatment recommendations. Insights into the deliberations of the task forces are provided in the Justification and Evidence to Decision Framework Highlights sections. The task forces also listed priority knowledge gaps for further research.

Resuscitation outcomes of infants that do not achieve a 5 min target SpO2 saturation

OBJECTIVE

To determine differences in the duration and level of resuscitation between infants that achieve a peripheral oxygen saturation (SpO₂) of 80% by 5 min compared with those who remain below 80% saturation.

STUDY DESIGN

Infants < 32 weeks GA were analyzed. Pulse rate, SpO₂, airway pressure, and fraction of inspired oxygen were collected during the first 10 min of life.

RESULTS

Two hundred and eighty-four infants were analyzed of which 100 had SpO₂ < 80% at 5 min of life. Composite outcome of death and any IVH was greater in the <80% at 5 min group. These infants had lower heart rates and lower SpO₂ despite increased mean airway pressure and higher FiO₂ (p < 0.001).

CONCLUSION

Infants <32 weeks GA that do not achieve a peripheral arterial saturation of 80% by 5 min of life experience more death or severe IVH. This association is amongst the strongest seen of any predictor of morbidity in the delivery room.

Is There a "Right" Amount of Oxygen for Preterm Infant Stabilization at Birth?

The amount of oxygen given to preterm infants within the first few minutes of birth is one of the most contentious issues in modern neonatology. Just two decades ago, pure oxygen (FiO2 1.0) was standard of care and oximetry monitoring was not routine. Due to concerns about oxidative stress and injury, clinicians rapidly adopted the practice of using less oxygen for the respiratory support of all infants, regardless of gestational maturity and pulmonary function. There is now evidence that initial starting fractional inspired oxygen may not be the only factor involved in providing optimum oxygenation and that the amount of oxygen given to babies within the first 10 min of life is a crucial factor in determining outcomes, including death and neurodevelopmental injury. In addition, evolving practice, such as non-invasive respiratory support and delayed cord clamping, need to be taken into consideration when considering oxygen delivery to preterm infants. This review will discuss evidence to date and address the major knowledge gaps that need to be answered in this pivotal aspect of neonatal practice.

Targeting Oxygen in Term and Preterm Infants Starting at Birth

Transition into the extrauterine world is characterized by a substantial increase in oxygen availability to tissue. Exact oxygen provision may be needed to avoid negative consequences of hypoxia or hyperoxia. For term and near-term infants, it is recommended to start with air and titrate the oxygen supplement to the saturation nomogram. However, oxygen supplementation in infants less than 32 weeks' gestation is an unsolved conundrum. At present, the inspired fraction of oxygen is set according to gestational age and blended to achieve targeted saturations and heart rates. Studies are still needed to overcome uncertainties about oxygen supplementation during preterm stabilization.

Effect of intermittent hypoxia or hyperoxia on lung development in preterm rat neonates during constant oxygen therapy

Impaired lung development is a major negative factor in the survival of preterm neonates. The present study was aimed to investigate the impact of constant oxygen, intermittent hyperoxia, and hypoxia on the lung development in preterm rat neonates. Neonatal rats were exposed to 40% O₂ with or without brief hyperoxia episodes (95% O₂ ) or brief hypoxia episodes (10% O₂ ) from day 0 to day 14, or to room air. The body weight, radical alveolar count (RAC), and total antioxidant capacity (TAOC) were significantly lower whereas the lung coefficient and malondialdehyde (MDA) were significantly higher in the hyperoxia and hypoxia groups than the air control and constant oxygen group at day 7, day 14, and day 21 after birth. The lung function indexes were reduced by intermittent hyperoxia and hypoxia. In contrast, the constant oxygen therapy increased the lung function. HIF-1α and VEGF expression were significantly increased by hypoxia and decreased by hyperoxia. The constant oxygen therapy only decreased the HIF-1α expression at day 14 and 21. In summary, the constant oxygen treatment promoted lung function without affecting the antioxidative capacity in preterm rat neonates. While intermittent hyperoxia and hypoxia inhibited lung development, decreased antioxidative capacity, and dysregulated HIF-1α/VEGF signaling in preterm rat neonates.

Optimal Inspired Fraction of Oxygen in the Delivery Room for Preterm Infants

Postnatal adaptation of preterm infants entails a series of difficulties among which the immaturity of the respiratory system is the most vital. To overcome respiratory insufficiency, caregivers attending in the delivery room use positive pressure ventilation and oxygen. A body of evidence in relation of oxygen management in the delivery room has been accumulated in recent years; however, the optimal initial inspired fraction of oxygen, the time to achieve specific oxygen saturation targets, and oxygen titration have not been yet clearly established. The aim of this review is to update the reader by critically analyzing the most relevant literature.

Initial Oxygen Use for Preterm Newborn Resuscitation: A Systematic Review With Meta-analysis

: media-1vid110.1542/5839981895001PEDS-VA_2018-1828Video Abstract CONTEXT: The International Liaison Committee on Resuscitation prioritized to review the initial fraction of inspired oxygen (Fio₂) during the resuscitation of preterm newborns.

OBJECTIVES

This systematic review and meta-analysis provides the scientific summary of initial Fio₂ in preterm newborns (<35 weeks' gestation) who receive respiratory support at birth.

DATA SOURCES

Medline, Embase, Evidence-Based Medicine Reviews, and Cumulative Index to Nursing and Allied Health Literature were searched between January 1, 1980 and August 10, 2018.

STUDY SELECTION

Studies were selected by pairs of independent reviewers in 2 stages with a Cohen's κ of 0.8 and 1.0.

DATA EXTRACTION

Pairs of independent reviewers extracted data, appraised the risk of bias (RoB), and assessed Grading of Recommendations Assessment, Development and Evaluation certainty.

RESULTS

Ten randomized controlled studies and 4 cohort studies included 5697 patients. There are no statistically significant benefits of or harms from starting with lower compared with higher Fio₂ in short-term mortality (n = 968; risk ratio = 0.83 [95% confidence interval 0.50 to 1.37]), long-term mortality, neurodevelopmental impairment, or other key preterm morbidities. A sensitivity analysis in which 1 study with a high RoB was excluded failed to reveal a reduction in mortality with initial low Fio₂ (n = 681; risk ratio = 0.63 [95% confidence interval 0.38 to 1.03]).

LIMITATIONS

The Grading of Recommendations Assessment, Development and Evaluation certainty of evidence was very low for all outcomes due to RoB, inconsistency, and imprecision.

CONCLUSIONS

The ideal initial Fio₂ for preterm newborns is still unknown, although the majority of newborns ≤32 weeks' gestation will require oxygen supplementation.

Oxygen Saturation Targeting During Delivery Room Stabilization: What Does This Mean for Regional Cerebral Oxygenation?

Objective: To investigate if preterm neonates with arterial oxygen saturation (SpO₂)<80% at 5 min after birth show different regional cerebral tissue oxygen saturation (rcStO₂), compared to infants reaching the target. Methods: Retrospective analysis of four prospective observational studies. Preterm neonates needing respiratory support during delivery room stabilization were included. Regional cerebral tissue oxygen saturation was measured with near-infrared spectroscopy (NIRS) during the first 15 min after birth along with SpO₂ and heart rate (HR). Neonates were divided into two groups: those with a 5-min SpO₂ ≥ 80% ("≥80% group") and those with a 5-min SpO₂ < 80% ("<80% group"). Groups were compared regarding rcStO₂, SpO₂, and HR. Furthermore, we analyzed whether a 5-min SpO₂ < 80% was associated with a rcStO₂ below the 10th percentile at the same time point. Results: 146 neonates were included, with 68 (47%) in the "≥80% group" and 78 (53%) in the "<80% group." Neonates in the " <80% group" had a significantly lower rcStO₂ (p < 0.001). Furthermore, 80.3% of neonates in the " <80% group" and 23.4% in the "≥80% group" had rcStO₂ values below the 10th percentile at 5 min (p < 0.001). HR was significantly lower at minute 3 and 4 in the " <80% group" (p < 0.002). Conclusion: Preterm infants needing respiratory support, who do not reach the SpO₂ target of 80% at 5 min after birth, show significantly diminished rcStO₂ values compared to neonates reaching the target.

National guidelines for delivery room management

The following guideline is designed to give recommendations for the routine care of all neonates immediately after delivery, and the resuscitation and delivery room approach of all high-risk infants in light of recent literature. The guideline has been prepared as three different parts. The first part is about routine procedures that have to be performed to all healthy term and preterm infants in delivery room care. The second part summaries the basic principles of resusucitation including the latest changes that were mentioned in the International Liaison Committee on Resuscitation (ILCOR)-2015 guideline. Recommendations about the delivery room management of rare clinical conditions have been discussed in the last part. The social, medical conditions, and the resourses of Turkey have also been taken into consideration in its preparation. We hope it will be useful for all pediatricians and neonatologists for use as a essential guideline in delivery room care.

Effect of various inspired oxygen concentrations on pulmonary and systemic hemodynamics and oxygenation during resuscitation in a transitioning preterm model

BACKGROUND

The Neonatal Resuscitation Program recommends initial resuscitation of preterm infants with low oxygen (O₂) followed by titration to target preductal saturations (SpO₂). We studied the effect of resuscitation with titrated O₂ on gas exchange, pulmonary, and systemic hemodynamics.

METHODOLOGY

Twenty-nine preterm lambs (127 d gestation) were randomized to resuscitation with 21% O₂ (n = 7), 100% O₂ (n = 6), or initiation at 21% and titrated to target SpO₂ (n = 16). Seven healthy term control lambs were ventilated with 21% O₂.

RESULTS

Preductal SpO₂ achieved by titrating O₂ was within the desired range similar to term lambs in 21% O₂. Resuscitation of preterm lambs with 21% and 100% O₂ resulted in SpO₂ below and above the target, respectively. Ventilation of preterm lambs with 100% O₂ and term lambs with 21% O₂ effectively decreased pulmonary vascular resistance (PVR). In contrast, preterm lambs with 21% O₂ and titrated O₂ demonstrated significantly higher PVR than term lambs on 21% O₂.

CONCLUSION(S)

Initial resuscitation with 21% O₂ followed by titration of O₂ led to suboptimal pulmonary vascular transition at birth in preterm lambs. Ventilation with 100% O₂ in preterm lambs caused hyperoxia but reduced PVR similar to term lambs on 21% O₂. Studies evaluating the initiation of resuscitation at a higher O₂ concentration followed by titration based on SpO₂ in preterm neonates are needed.

Hemoglobin oxygen saturation targets in the neonatal intensive care unit: Is there a light at the end of the tunnel? 1

The optimal oxygenation target needed to prevent the extremes of hypoxia and oxygen toxicity in premature and sick newborns has been the subject of much research and debate. The advent of the pulse oximeter has allowed the continuous monitoring of oxyhemoglobin saturation and the delivery of oxygen with greater precision. Well-run, large clinical trials to determine the safest oxygen concentration have led to several revisions in guidelines for neonatal care. However, monitoring of oxyhemoglobin saturation has its limitations and does not provide a comprehensive assessment of tissue oxygenation. To identify optimal oxygen therapy, various other factors (partial pressure of arterial carbon dioxide, hemoglobin concentration, blood pH, and tissue metabolic demand) that influence perfusion and tissue oxygenation need to be considered.

Outcomes of oxygen saturation targeting during delivery room stabilisation of preterm infants

OBJECTIVE

To determine the association between SpO₂ at 5 min and preterm infant outcomes.

DESIGN

Data from 768 infants <32 weeks gestation from 8 randomised controlled trials (RCTs) of lower (≤0.3) versus higher (≥0.6) initial inspiratory fractions of oxygen (FiO₂) for resuscitation, were examined.

SETTING

Individual patient analysis of 8 RCTs INTERVENTIONS: Lower (≤0.3) versus higher (≥0.6) oxygen resuscitation strategies targeted to specific predefined SpO₂ before 10 min of age.

PATIENTS

Infants <32 weeks gestation.

MAIN OUTCOME MEASURES

Relationship between SpO₂ at 5 min, death and intraventricular haemorrhage (IVH) >grade 3.

RESULTS

5 min SpO₂ data were obtained from 706 (92%) infants. Only 159 (23%) infants met SpO₂ study targets and 323 (46%) did not reach SpO₂80%. Pooled data showed decreased likelihood of reaching SpO₂80% if resuscitation was initiated with FiO₂ <0.3 (OR 2.63, 95% CI 1.21 to 5.74, p<0.05). SpO₂ <80% was associated with lower heart rates (mean difference -8.37, 95% CI -15.73 to -1.01, *p<0.05) and after accounting for confounders, with IVH (OR 2.04, 95% CI 1.01 to 4.11, p<0.05). Bradycardia (heart rate <100 bpm) at 5 min increased risk of death (OR 4.57, 95% CI 1.62 to 13.98, p<0.05). Taking into account confounders including gestation, birth weight and 5 min bradycardia, risk of death was significantly increased with time taken to reach SpO₂80%.

CONCLUSION

Not reaching SpO₂80% at 5 min is associated with adverse outcomes, including IVH. Whether this is because of infant illness or the amount of oxygen that is administered during stabilisation is uncertain and needs to be examined in randomised trials.

Oxygen Therapy in the Delivery Room: What Is the Right Dose?

Oxygen is the most commonly used medicine used during neonatal resuscitation in the delivery room. Oxygen therapy in delivery room should be used judiciously to avoid oxygen toxicity while delivering sufficient oxygen to prevent hypoxia. Measurement of appropriate oxygenation relies on pulse oximetry, but adequate ventilation and perfusion are equally important for oxygen delivery. In this article, we review oxygenation while transitioning from fetal to neonatal life, the importance of appropriate oxygen therapy, its measurement in the delivery room, and current recommendations for oxygen therapy and its limitations.

A review of international clinical practice guidelines for the use of oxygen in the delivery room resuscitation of preterm infants

AIM

To collate and assess international clinical practice guidelines (CPG) to determine current recommendations guiding oxygen management for respiratory stabilisation of preterm infants at delivery.

METHODS

A search of public databases using the terms 'clinical practice guidelines', 'preterm', 'oxygen' and 'resuscitation' was made and complemented by direct query to consensus groups, resuscitation expert committees and clinicians. Data were extracted to include the three criteria for assessment: country of origin, gestation and initial FiO₂ and target SpO₂ for the first 10 minutes of life.

RESULTS

A total of 45 CPGs were identified: 36 provided gestation specific recommendations (<28 to <37 weeks) while eight distinguished only between 'preterm' and 'term'. The most frequently recommended initial FiO₂ were between 0.21 and 0.3 (n = 17). Most countries suggested altering FiO₂ to meet SpO₂ targets recommended by expert committees, However, specific five-minute SpO₂ targets differed by up to 20% (70-90%) between guidelines. Five countries did not specify SpO₂ targets.

CONCLUSION

CPG recommendations for delivery room oxygen management of preterm infants vary greatly, particularly in regard to gestational ages, initial FiO₂ and SpO₂ targets and most acknowledge the lack of evidence behind these recommendations. Sufficiently large and well-designed randomised studies are needed to inform on this important practice.

Reducing Brain Injury of Preterm Infants in the Delivery Room

Cerebrovascular injury is one of the major detrimental consequences of preterm birth. Recent studies have focused their attention on factors that contribute to the development of brain lesions immediately after birth. Among those factors, hypothermia and lower cerebral oxygen saturation during delivery room resuscitation and high tidal volumes delivered during respiratory support are associated with increased risk of severe neurologic injury. In preterm infants, knowledge about causes and prevention of brain injury must be applied before and at birth. Preventive and therapeutic approaches, including correct timing of cord clamping, monitoring of physiological changes during delivery room resuscitation using pulse oximetry, respiratory function monitoring, near infrared spectroscopy, and alpha EEG, may minimize brain injury, Furthermore, postnatal administration of caffeine or other potential novel treatments (e.g., proangiogenic therapies, antioxidants, hormones, or stem cells) might improve long-term neurodevelopmental outcomes in preterm infants.

Impact of the Neonatal Resuscitation Program-Recommended Low Oxygen Strategy on Outcomes of Infants Born Preterm

OBJECTIVE

To evaluate the impact of the Neonatal Resuscitation Program (NRP)-recommended low oxygen strategy (LOX) on neonatal morbidities, mortality, and neurodevelopmental outcomes in neonates born preterm.

STUDY DESIGN

In March 2011, Parkland Hospital changed from a high oxygen strategy (HOX) of resuscitation with initial 100% oxygen and targeting 85%-94% oxygen saturation for delivery room resuscitation to a LOX with initial 21% oxygen and titrating oxygen to meet NRP-recommended transitional target saturations. Neonates ≤28 weeks' gestational age born between August 2009 and April 2012 were identified. In this retrospective, observational study, neonates exposed to LOX vs HOX were compared for short-term morbidity, mortality, and long-term neurodevelopmental outcomes. Regression analysis was performed to control for confounding variables.

RESULTS

Of 199 neonates, 110 were resuscitated with HOX and 89 with LOX. Compared with HOX, neonates exposed to LOX had lower oxygen exposure in the delivery room (5.2 ± 1.5 vs 7.8 ± 2.8 [∑FiO2 × time min], P < .01), spent fewer days on oxygen (30 [5, 54] vs 46 [11, 82], P = .01), and had lower odds of developing bronchopulmonary dysplasia (aOR 0.4 [0.2, 0.9]). There was no difference in mortality (17 [20%] vs 20 [18%]), but neonates exposed to LOX had greater motor composite scores on Bayley Scales of Infant and Toddler Development-Third edition assessment (91 [85, 97] vs 88 [76, 94], P < .01).

CONCLUSION

The NRP-recommended LOX strategy was associated with improved respiratory morbidities and neurodevelopmental outcomes with no increase in mortality. Prospective trials to confirm the optimal oxygen strategy for the resuscitation of neonates born preterm are needed.

Delivery room interventions to prevent bronchopulmonary dysplasia in extremely preterm infants

Bronchopulmonary dysplasia (BPD) is the most common chronic respiratory complication of preterm birth. Preterm infants are at risk for acute lung injury immediately after birth, which predisposes to BPD. In this article, we review the current evidence for interventions applied during neonatal transition (delivery room and first postnatal hours of life) to prevent BPD in extremely preterm infants: continuous positive airway pressure (CPAP), sustained lung inflation, supplemental oxygen use during neonatal resuscitation, and surfactant therapy including less-invasive surfactant administration. Preterm infants should be stabilized with CPAP in the delivery room, reserving invasive mechanical ventilation for infants who fail non-invasive respiratory support. For infants who require endotracheal intubation and mechanical ventilation soon after birth, surfactant should be given early (<2 h of life). We recommend prudent titration of supplemental oxygen in the delivery room to achieve targeted oxygen saturations. Promising interventions that may further reduce BPD, such as sustained inflation and non-invasive surfactant administration, are currently under investigation.

Neurodevelopmental outcomes of preterm infants resuscitated with different oxygen concentration at birth

OBJECTIVE

To compare the neurodevelopmental outcomes at 18 to 21 months corrected age (CA) of infants born at <29 weeks that received room air, an intermediate oxygen concentration or 100% oxygen at the initiation of resuscitation.

STUDY DESIGN

In this retrospective cohort study, we compared neonatal and neurodevelopmental outcomes at 18 to 21 months CA among inborn infants born before 29 weeks' gestation that received room air, intermediate oxygen concentration or 100% oxygen at the initiation of resuscitation.

RESULTS

Of 1509 infants, 445 received room air, 483 received intermediate oxygen concentrations and 581 received 100% oxygen. Compared to infants that received room air, the primary outcome of death or neurodevelopmental impairment (NDI) was not different in intermediate oxygen (adjusted odds ratio (aOR) 1.01; 95% confidence interval (CI) 0.77, 1.34) or 100% oxygen (aOR 1.03; 95% CI 0.78, 1.35). Compared to room air, there was no difference in odds of death or severe NDI in intermediate oxygen (aOR 1.14; 95% CI 0.82, 1.58) or 100% oxygen group (aOR 1.22; 95% CI 0.90, 1.67). The odds of severe NDI among survivors were significantly higher in infants that received 100% oxygen as compared to room air (aOR 1.57, 95% CI 1.05, 2.35).

CONCLUSIONS

We observed no significant difference in the primary composite outcomes of death or NDI and death or severe NDI at 18 to 21 months CA between infants that received room air, intermediate oxygen concentration or 100% oxygen at the initiation of resuscitation. However, use of 100% oxygen was associated with increased odds of severe NDI among survivors as compared to room air.

Prevention of bronchopulmonary dysplasia: current strategies

Bronchopulmonary dysplasia (BPD) is one of the few diseases affecting premature infants that have continued to evolve since its first description about half a century ago. The current form of BPD, a more benign and protracted respiratory failure in extremely preterm infants, is in contrast to the original presentation of severe respiratory failure with high mortality in larger premature infants. This new BPD is end result of complex interplay of various antenatal and postnatal factors causing lung injury and subsequent abnormal repair leading to altered alveolar and vascular development. The change in clinical and pathologic picture of BPD over time has resulted in new challenges in developing strategies for its prevention and management. While some of these strategies like Vitamin A supplementation, caffeine and volume targeted ventilation have stood the test of time, others like postnatal steroids are being reexamined with great interest in last few years. It is quite clear that BPD is unlikely to be eliminated unless some miraculous strategy cures prematurity. The future of BPD prevention will probably be a combination of antenatal and postnatal strategies acting on multiple pathways to minimize lung injury and abnormal repair as well as promote normal alveolar and vascular development.

Management of Extremely Low Birth Weight Infants in Delivery Room

Extremely low birth weight (ELBW) infants are particularly vulnerable at birth, and stabilization in the delivery room (DR) remains challenging. After birth, ELBW infants are at high risk for the development of thermal dysregulation, respiratory insufficiency, and hemodynamic instability due to their immature physiology and anatomy. Although successful stabilization facilitates the transition and reduces acute morbidity, suboptimal care in the DR could cause long-term sequelae. This review addresses the challenges in stabilization in the DR and current neonatal resuscitation guidelines and recommendations.

Continuous noninvasive monitoring in the neonatal ICU

PURPOSE OF REVIEW

Standard hemodynamic monitoring such as heart rate and systemic blood pressure may only provide a crude estimation of organ perfusion during neonatal intensive care. Pulse oximetry monitoring allows for continuous noninvasive monitoring of hemoglobin oxygenation and thus provides estimation of end-organ oxygenation. This review aims to provide an overview of pulse oximetry and discuss its current and potential clinical use during neonatal intensive care.

RECENT FINDINGS

Technological advances in continuous assessment of dynamic changes in systemic oxygenation with pulse oximetry during transition to extrauterine life and beyond provide additional details about physiological interactions among the key hemodynamic factors regulating systemic blood flow distribution along with the subtle changes that are frequently transient and undetectable with standard monitoring.

SUMMARY

Noninvasive real-time continuous systemic oxygen monitoring has the potential to serve as biomarkers for early-organ dysfunction, to predict adverse short-term and long-term outcomes in critically ill neonates, and to optimize outcomes. Further studies are needed to establish values predicting adverse outcomes and to validate targeted interventions to normalize abnormal values to improve outcomes.

Higher or lower oxygen for delivery room resuscitation of preterm infants below 28 completed weeks gestation: a meta-analysis

OBJECTIVE

To systematically review outcomes of infants ≤28+6 weeks gestation randomised to resuscitation with low (≤0.3) vs high (≥0.6) fraction of inspired oxygen (FiO₂) at delivery.

DESIGN

Systematic review of randomised controlled trials of low (≤0.3) vs high (≥0.6) FiO₂ resuscitation. Information was obtained from databases (Medline/Pub Med, EMBASE, ClinicalTrials.gov, Cochrane) and meeting abstracts between 1990 to 2015. Search index terms: preterm/ resuscitation/oxygen. Data for infants ≤28+6 weeks gestation were independently extracted and pooled using a random effects model. Analyses were performed with Revman V.5.

MAIN OUTCOME MEASURES

Death in hospital, bronchopulmonary dysplasia (BPD), retinopathy of prematurity >grade 2 (ROP), intraventricular haemorrhage >grade 2 (IVH), patent ductus arteriosus (PDA) and necrotising enterocolitis (NEC).

RESULTS

A total of 251 and 253 infants were enrolled in 8 studies (6 masked, 2 unmasked) in the lower and higher oxygen groups, respectively, (mean gestation 26 weeks) between 2005 and 2014. There were no differences in BPD (relative risk, 95% CIs 0.88 (0.68 to 1.14)), IVH (0.81 (0.52 to 1.27)), ROP (0.82 (0.46 to 1.46)), PDA (0.95 (0.80 to 1.14)) and NEC (1.61 (0.67 to 3.36)) and overall mortality (0.99 (0.52 to 1.91)). Mortality was lower in low oxygen arms of masked studies (0.46 (0.23 to 0.92), p=0.03) and higher in low oxygen arms of unmasked studies (1.94 (1.02 to 3.68), p=0.04).

CONCLUSIONS

There is no difference in the overall risk of death or other common preterm morbidities after resuscitation is initiated at delivery with lower (≤0.30) or higher (≥0.6) FiO₂ in infants ≤28+6 weeks gestation. The opposing results for masked and unmasked trials may represent a Type I error, emphasising the need for larger, well designed studies.

Targeted Oxygen in the Resuscitation of Preterm Infants, a Randomized Clinical Trial

BACKGROUND AND OBJECTIVES

Lower concentrations of oxygen (O₂) (≤30%) are recommended for preterm resuscitation to avoid oxidative injury and cerebral ischemia. Effects on long-term outcomes are uncertain. We aimed to determine the effects of using room air (RA) or 100% O₂ on the combined risk of death and disability at 2 years in infants <32 weeks' gestation.

METHODS

A randomized, unmasked study designed to determine major disability and death at 2 years in infants <32 weeks' gestation after delivery room resuscitation was initiated with either RA or 100% O₂ and which were adjusted to target pulse oximetry of 65% to 95% at 5 minutes and 85% to 95% until NICU admission.

RESULTS

Of 6291 eligible patients, 292 were recruited and 287 (mean gestation: 28.9 weeks) were included in the analysis (RA: n = 144; 100% O₂: n = 143). Recruitment ceased in June 2014, per the recommendations of the Data and Safety Monitoring Committee owing to loss of equipoise for the use of 100% O₂. In non-prespecified analyses, infants <28 weeks who received RA resuscitation had higher hospital mortality (RA: 10 of 46 [22%]; than those given 100% O₂: 3 of 54 [6%]; risk ratio: 3.9 [95% confidence interval: 1.1-13.4]; P = .01). Respiratory failure was the most common cause of death (n = 13).

CONCLUSIONS

Using RA to initiate resuscitation was associated with an increased risk of death in infants <28 weeks' gestation. This study was not a prespecified analysis, and it was underpowered to address this post hoc hypothesis reliably. Additional data are needed.

Survival and Neurodevelopmental Outcomes of Preterms Resuscitated With Different Oxygen Fractions

BACKGROUND AND OBJECTIVES

Stabilization of preterm infants after birth frequently requires oxygen supplementation. At present the optimal initial oxygen inspiratory fraction (Fio₂) for preterm stabilization after birth is still under debate. We aimed to compare neurodevelopmental outcomes of extremely preterm infants at 24 months corrected age randomly assigned to be stabilized after birth with an initial Fio₂ of 0.3 versus 0.6 to 0.65 in 3 academic centers from Spain and the Netherlands.

METHODS

Randomized, controlled, double-blinded, multicenter, international clinical trial enrolling preterm infants <32 weeks' gestation assigned to an initial Fio₂ of 0.3 (Lowox group) or 0.6 to 0.65 (Hiox group). During stabilization, arterial pulse oxygen saturation and heart rate were continuously monitored and Fio₂ was individually titrated to keep infants within recommended ranges. At 24 months, blinded researchers used the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) to assess visual acuity, neurosensory deafness, and language skills.

RESULTS

A total of 253 infants were recruited and 206 (81.4%) completed follow-up. No differences in perinatal characteristics, oxidative stress, or morbidities during the neonatal period were assessed. Mortality at hospital discharge or when follow-up was completed didn't show differences between the groups. No differences regarding Bayley-III scale scores (motor, cognitive, and language composites), neurosensorial handicaps, cerebral palsy, or language skills between groups were found.

CONCLUSIONS

The use of an initial lower (0.3) or higher (0.6-0.65) Fio₂ during stabilization of extremely preterm infants in the delivery room does not influence survival or neurodevelopmental outcomes at 24 months.

[Changes in the international recommendations on neonatal stabilisation and resuscitation (2015)]

The International Liaison Committee on Resuscitation (ILCOR) recommendations provide a universal guide of measures to support the transition and resuscitation of newborn after their birth. This guide is expected to be adapted by local groups or committees on resuscitation, according to their own circumstances. The objective of this review is to analyse the main changes, to discuss several of the controversies that have appeared since 2010, and contrasting with other national and international organisations, such as European Resuscitation Council (ERC), American Heart Association (AHA), or the Australian-New Zealand Committee on Resuscitation (ANZCOR). Thus, the Neonatal Resuscitation Group of the Spanish Society of Neonatology (GRN-SENeo) aims to give clear answers to many of the questions when different options are available, generating the forthcoming recommendations of our country to support the transition and/or resuscitation of a newborn after birth, safely and effectively.

The fetal circulation, pathophysiology of hypoxemic respiratory failure and pulmonary hypertension in neonates, and the role of oxygen therapy

Neonatal hypoxemic respiratory failure (HRF), a deficiency of oxygenation associated with insufficient ventilation, can occur due to a variety of etiologies. HRF can result when pulmonary vascular resistance (PVR) fails to decrease at birth, leading to persistent pulmonary hypertension of newborn (PPHN), or as a result of various lung disorders including congenital abnormalities such as diaphragmatic hernia, and disorders of transition such as respiratory distress syndrome, transient tachypnea of newborn and perinatal asphyxia. PVR changes throughout fetal life, evident by the dynamic changes in pulmonary blood flow at different gestational ages. Pulmonary vascular transition at birth requires an interplay between multiple vasoactive mediators such as nitric oxide, which can be potentially inactivated by superoxide anions. Superoxide anions have a key role in the pathophysiology of HRF. Oxygen (O2) therapy, used in newborns long before our knowledge of the complex nature of HRF and PPHN, has continued to evolve. Over time has come the discovery that too much O2 can be toxic. Recommendations on the optimal inspired O2 levels to initiate resuscitation in term newborns have ranged from 100% (pre 1998) to the currently recommended use of room air (21%). Questions remain about the most effective levels, particularly in preterm and low birth weight newborns. Attaining the appropriate balance between hypoxemia and hyperoxemia, and targeting treatments to the pathophysiology of HRF in each individual newborn are critical factors in the development of improved therapies to optimize outcomes.

Oxygen Supplementation to Stabilize Preterm Infants in the Fetal to Neonatal Transition: No Satisfactory Answer

Fetal life elapses in a relatively low oxygen environment. Immediately after birth with the initiation of breathing, the lung expands and oxygen availability to tissue rises by twofold, generating a physiologic oxidative stress. However, both lung anatomy and function and the antioxidant defense system do not mature until late in gestation, and therefore, very preterm infants often need respiratory support and oxygen supplementation in the delivery room to achieve postnatal stabilization. Notably, interventions in the first minutes of life can have long-lasting consequences. Recent trials have aimed to assess what initial inspiratory fraction of oxygen and what oxygen targets during this transitional period are best for extremely preterm infants based on the available nomogram. However, oxygen saturation nomogram informs only of term and late preterm infants but not on extremely preterm infants. Therefore, the solution to this conundrum may still have to wait before a satisfactory answer is available.