Surfactant therapy in preterm infants with respiratory distress syndrome and in near-term or term newborns with acute RDS

Surfactant administration methods for premature newborns: LISA vs. INSURE comparative analysis

INTRODUCTION

Respiratory Distress Syndrome (RDS) is the most common respiratory disorder among premature infants. The use of surfactant has significantly reduced respiratory complications and mortality. There are two conventional methods for administering surfactant: Intubate-Surfactant-Extubate (INSURE) and Less Invasive Surfactant Administration (LISA). This study aims to compare the effects of surfactant administration using these two methods on the treatment outcomes of premature newborns.

MATERIALS AND METHODS

In this retrospective cohort study, we included 100 premature newborns with RDS and spontaneous breathing who were admitted to the Neonatal Intensive Care Unit of Besat Hospital in Sanandaj city in 2021. Exclusion criteria comprised congenital anomalies and the needing for intubation for resuscitation at birth. The outcomes of epmericaly trated with two methods were compared: the LISA (50 neonates) and the INSURE (50 neonates). Our interesting outcomes were needing for mechanical ventilation, duration of ventilation, pneumothorax, pulmonary hemorrhage, severe retinopathy, CPAP duration, and bronchopulmonary dysplasia. Finally, we entered the data into STATA-14 statistical software and analyzed it using chi-square and t-tests.

RESULTS

In this study, 69% of the neonates were boys. The LISA group exhibited significantly lower rates of need for mechanical ventilation (P = 0.003) and ventilation duration (P < 0.001) compared to the INSURE group. Conversely, there were no significant differences between the two groups (P > 0.05) in terms of pneumothorax, pulmonary hemorrhage, severe retinopathy, CPAP duration, and bronchopulmonary dysplasia rates.

CONCLUSION

The results of this study suggest that the LISA method is a safe and non-invasive approach for surfactant administration. Notably, it resulted in a reduced need for mechanical ventilation and decreased ventilation duration compared to the INSURE method.

Artificial Intelligence-Driven Respiratory Distress Syndrome Prediction for Very Low Birth Weight Infants: Korean Multicenter Prospective Cohort Study

BACKGROUND

Respiratory distress syndrome (RDS) is a disease that commonly affects premature infants whose lungs are not fully developed. RDS results from a lack of surfactant in the lungs. The more premature the infant is, the greater is the likelihood of having RDS. However, even though not all premature infants have RDS, preemptive treatment with artificial pulmonary surfactant is administered in most cases.

OBJECTIVE

We aimed to develop an artificial intelligence model to predict RDS in premature infants to avoid unnecessary treatment.

METHODS

In this study, 13,087 very low birth weight infants who were newborns weighing less than 1500 grams were assessed in 76 hospitals of the Korean Neonatal Network. To predict RDS in very low birth weight infants, we used basic infant information, maternity history, pregnancy/birth process, family history, resuscitation procedure, and test results at birth such as blood gas analysis and Apgar score. The prediction performances of 7 different machine learning models were compared, and a 5-layer deep neural network was proposed in order to enhance the prediction performance from the selected features. An ensemble approach combining multiple models from the 5-fold cross-validation was subsequently developed.

RESULTS

Our proposed ensemble 5-layer deep neural network consisting of the top 20 features provided high sensitivity (83.03%), specificity (87.50%), accuracy (84.07%), balanced accuracy (85.26%), and area under the curve (0.9187). Based on the model that we developed, a public web application that enables easy access for the prediction of RDS in premature infants was deployed.

CONCLUSIONS

Our artificial intelligence model may be useful for preparations for neonatal resuscitation, particularly in cases involving the delivery of very low birth weight infants, as it can aid in predicting the likelihood of RDS and inform decisions regarding the administration of surfactant.

Cathelicidin Attenuates Hyperoxia-Induced Lung Injury by Inhibiting Ferroptosis in Newborn Rats

High oxygen concentrations are often required to treat newborn infants with respiratory distress but have adverse effects, such as increased oxidative stress and ferroptosis and impaired alveolarization. Cathelicidins are a family of antimicrobial peptides that exhibit antioxidant activity, and they can reduce hyperoxia-induced oxidative stress. This study evaluated the effects of cathelicidin treatment on lung ferroptosis and alveolarization in hyperoxia-exposed newborn rats. Sprague Dawley rat pups were either reared in room air (RA) or hyperoxia (85% O₂) and then randomly given cathelicidin (8 mg/kg) in 0.05 mL of normal saline (NS), or NS was administered intraperitoneally on postnatal days from 1-6. The four groups obtained were as follows: RA + NS, RA + cathelicidin, O₂ + NS, and O₂ + cathelicidin. On postnatal day 7, lungs were harvested for histological, biochemical, and Western blot analyses. The rats nurtured in hyperoxia and treated with NS exhibited significantly lower body weight and cathelicidin expression, higher Fe²⁺, malondialdehyde, iron deposition, mitochondrial damage (TOMM20), and interleukin-1β (IL-1β), and significantly lower glutathione, glutathione peroxidase 4, and radial alveolar count (RAC) compared to the rats kept in RA and treated with NS or cathelicidin. Cathelicidin treatment mitigated hyperoxia-induced lung injury, as demonstrated by higher RAC and lower TOMM20 and IL-1β levels. The attenuation of lung injury was accompanied by decreased ferroptosis. These findings indicated that cathelicidin mitigated hyperoxia-induced lung injury in the rats, most likely by inhibiting ferroptosis.

Effect of surfactant dose on outcomes in preterm infants with respiratory distress syndrome: the OPTI-SURF study protocol

INTRODUCTION

Respiratory distress syndrome is a condition seen in preterm infants primarily due to surfactant insufficiency. European guidelines recommend the dose and method of surfactant administration. However, in routine practice, clinicians often use a 'whole vial' approach to surfactant dosing. The aim of this study is to assess whether in preterm infants of gestational age 36⁺⁶ weeks^+days or less, a low first dose of surfactant (100-130 mg/kg) compared with a high first dose (170-200 mg/kg) affects survival with no mechanical ventilation on either on postnatal days 3 and 4, and other outcomes.

METHODS AND ANALYSIS

In this prospective, observational study, we will use the National Neonatal Research Database as the main data source. We will obtain additional information describing the dose and method of surfactant administration through the neonatal EPR system. We will use propensity scores to form matched groups with low first dose and high first dose for comparison.

ETHICS AND DISSEMINATION

This study was approved by the West Midlands-Black Country Research Ethics Committee (REC reference: 18/WM/0132; IRAS project ID: 237111). The results of the research will be made publicly available through presentations at local, national or international conferences and will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

NCT03808402; Pre-results.

Attitudes of Mothers Regarding Willingness to Enroll Their Children in Research

This study assessed mothers' perspectives regarding research involvement by their children, factors that might affect perceptions of research risks, and attitudes regarding willingness to enroll children in research. Participants completed a survey on Amazon Mechanical Turk. Mothers were less inclined to enroll children in research involving procedures posing higher risk (regression coefficient = -0.51). Mothers without mental health issues with children without health issues were more sensitive to risk than mothers without mental health issues with children with health issues (estimated difference = 0.49). Mothers with mental health issues were more willing than mothers without mental health issues to enroll children in research (regression coefficient = -0.90). Among mothers with mental health issues, having a child with a health issue was associated with increased willingness to enroll in research, compared with having children without health issues (estimated difference = 0.65).

Evaluating the use of corticosteroids in preventing and treating bronchopulmonary dysplasia in preterm neonates

Approximately 15 million babies worldwide are born premature, and complications of prematurity are one of the leading causes of death in neonates. Neonatal respiratory distress syndrome (NRDS) and bronchopulmonary dysplasia (BPD) are two of the most common and serious consequences of prematurity. Synthetic corticosteroids, including dexamethasone, have been central in efforts to treat and prevent BPD. There is strong evidence to show that prenatal corticosteroids reduce infant mortality and the incidence of NRDS, leading to their widespread use in obstetric units. However, data suggest that they are not as effective in reducing the incidence of BPD as NRDS, which may be due to the multifactorial pathogenesis of BPD. On the other hand, the use of postnatal corticosteroids in preterm infants is much more controversial. They have been shown to improve lung function and help in reducing the need for mechanical ventilation. These benefits, however, are associated with a range of adverse short- and long-term effects. This review will discuss the benefits and consequences of corticosteroids in treating BPD and will examine alternative treatments and future research that may improve the understanding of BPD and inform clinical practice.

Therapeutic potential of mesenchymal stem cells for pulmonary complications associated with preterm birth

Preterm infants frequently suffer from pulmonary complications resulting in significant morbidity and mortality. Physiological and structural lung immaturity impairs perinatal lung transition to air breathing resulting in respiratory distress. Mechanical ventilation and oxygen supplementation ensure sufficient oxygen supply but enhance inflammatory processes which might lead to the establishment of a chronic lung disease called bronchopulmonary dysplasia (BPD). Current therapeutic options to prevent or treat BPD are limited and have salient side effects, highlighting the need for new therapeutic approaches. Mesenchymal stem cells (MSCs) have demonstrated therapeutic potential in animal models of BPD. This review focuses on MSC-based therapeutic approaches to treat pulmonary complications and critically compares results obtained in BPD models. Thereby bottlenecks in the translational systems are identified that are preventing progress in combating BPD. Notably, current animal models closely resemble the so-called "old" BPD with profound inflammation and injury, whereas clinical improvements shifted disease pathology towards a "new" BPD in which arrest of lung maturation predominates. Future studies need to evaluate the utility of MSC-based therapies in animal models resembling the "new" BPD though promising in vitro evidence suggests that MSCs do possess the potential to stimulate lung maturation. Furthermore, we address the mode-of-action of MSC-based therapies with regard to lung development and inflammation/fibrosis. Their therapeutic efficacy is mainly attributed to an enhancement of regeneration and immunomodulation due to paracrine effects. In addition, we discuss current improvement strategies by genetic modifications or precondition of MSCs to enhance their therapeutic efficacy which could also prove beneficial for BPD therapies.

Prematurity, Birth Weight, and Socioeconomic Status Are Linked to Atypical Diurnal Hypothalamic-Pituitary-Adrenal Axis Activity in Young Adults

In a prospective, case-controlled longitudinal design, 180 preterm and fullterm infants who had been enrolled at birth participated in a comprehensive assessment battery at age 23. Of these, 149 young adults, 34 formerly full-term and 115 formerly preterm (22 healthy preterm, 48 with medical complications, 21 with neurological complications, and 24 small for gestational age) donated five saliva samples from a single day that were assayed for cortisol to assess diurnal variation of the hypothalamic-pituitary-adrenal (HPA) axis. Analyses were conducted to determine whether prematurity category, birth weight, and socioeconomic status were associated with differences in HPA axis function. Pre- and perinatal circumstances associated with prematurity influenced the activity of this environmentally sensitive physiological system. Results are consistent with the theory of Developmental Origins of Health and Disease and highlight a possible mechanism for the link between prematurity and health disparities later in life.

Current Issues and Challenges in the Use of Aerosolized Surfactant for Respiratory Distress Syndrome in the Newborns

BACKGROUND: Surfactant replacement therapy is a recognized treatment for respiratory distress syndrome (RDS) in the newborns. Over the past 30 years, human and animal trials have been performed regarding administration of aerosolized surfactant to the injured lung, however the result has been unsatisfactory when compared with instilled surfactant delivery via endotracheal tube (ETT). This review aims to investigate the current issues, challenges and future recommendation of aerosolized surfactant therapy.CONTENT: Five randomized clinical trials in humans and 13 animal trials met the inclusion criteria and were reviewed. Most animal trials agree that this method of treatment is feasible. However, human trials presented conflicting results, and generally showed it to be ineffective. When compared with surfactant delivery via ETT, aerosolized surfactant is less effective in improving respiratory function.SUMMARY: The current data from human trials does not support the implementation of aerosolized surfactant therapy to treat newborns with RDS. Further research is necessary to improve nebulization, delivery, distribution and deposition in the lung, to investigate aerosolized surfactant delivery via ETT and to determine the appropriate dose.KEYWORDS: surfactant, aerosol, prematurity, respiratory distress syndrome

Surfactant protein D deficiency increases lung injury during endotoxemia

Acute lung injury (ALI) and its severe form, acute respiratory distress syndrome (ARDS), are major causes of acute respiratory failure with high rates of morbidity and mortality. Although surfactant protein (SP)-D plays a critical role in pulmonary innate immunity and several clinical studies suggest that this protein may be implicated in the pathophysiology of ARDS, little is known regarding the function of SP-D in ARDS. In the present study, we induced indirect lung injury by intraperitoneal injection of LPS and direct lung injury by intratracheal injection of LPS in wild-type and Sftpd(-/-) mice to elucidate the role of SP-D during ALI/ARDS. Results indicate that pulmonary levels of IL-6 and TNF-α were higher in Sftpd(-/-) mice when compared with wild-type mice. However, the magnitude of this difference was 10-fold greater after indirect lung injury compared with direct lung injury. After indirect lung injury, there was a 2-fold increase in the number of pulmonary monocyte/macrophages in the Sftpd(-/-) mice when compared with wild-type mice, whereas pulmonary neutrophils were not increased. After indirect injury, the concentration of granulocyte-macrophage colony stimulating factor (GM-CSF) was approximately 5-fold greater in Sftpd(-/-) mice than wild-type mice. In contrast, after direct injury, the concentration of GM-CSF was 20-fold less in Sftpd(-/-) mice than wild-type mice. Despite increased inflammatory cells and markers of inflammation, survival in Sftpd(-/-) mice after indirect lung injury was paradoxically increased. In conclusion, these results suggest that SP-D inhibits pulmonary inflammation and migration of peripheral monocyte/macrophages into the lung through GM-CSF-dependent pathways during indirect lung injury.

The role of surfactant treatment in preterm infants and term newborns with acute respiratory distress syndrome

Surfactant treatment in preterm infants and term newborns with (acute respiratory distress syndrome) ARDS-like severe respiratory failure has become part of an individualized treatment strategy in many intensive care units around the world. These babies constitute heterogeneous groups of gestational ages, lung maturity, as well as of the underlying disease processes and postnatal interventions. The pathophysiology of respiratory failure in preterm infants is characterized by a combination of primary surfactant deficiency and surfactant inactivation as a result of plasma proteins leaking into the airways from areas of epithelial disruption and injury. Various pre- and postnatal factors, such as exposure to chorioamnionitis, pneumonia, sepsis and asphyxia, induce an injurious inflammatory response in the lungs of preterm infants, which may subsequently affect surfactant function, synthesis and alveolar stability. Surfactant inactivation--and dysfunction--is also a hallmark in newborns with meconium aspiration syndrome (MAS), pneumonia and other disorders affecting the pulmonary function. Although for the majority of suggested indications no data from randomized controlled trials exist, a surfactant replacement that counterbalances surfactant inactivation seems to improve oxygenation and lung function in many babies with ARDS without any apparent negative side effects. Newborns with MAS will definitely benefit from a reduced need for extracorporeal membrane oxygenation (ECMO). Clinical experience seems to justify surfactant treatment in neonates with ARDS.