Does the use of antenatal corticosteroids reduce respiratory morbidity in babies born in late preterm period?

BACKGROUND: The aim of this study is to determine the effectiveness of antenatal corticosteroid in reducing respiratory morbidity in babies born in the late preterm period. METHODS: Two hundred and eighty-six pregnant women at risk of having a late preterm delivery were studied. One hundred and forty-three (143) served as the cases and were given 2 doses of 12 mg intramuscular dexamethasone 12 h apart, while 143 served as the controls and were given a similar quantity of placebo. The women were followed up prospectively and data were collected on the pregnant women and their newborns on a standardized form. The neonates were assessed for acute respiratory distress syndrome and transient tachypnea of the newborn based on clinical signs, symptoms, and chest x-ray results (when indicated). The primary outcome was the occurrence of neonatal respiratory morbidity. RESULTS: The primary outcome occurred in 5 out of 130 infants (3.8%) in the dexamethasone group and 31 out of 122 (25.4%) in the placebo group (P value = 0.000003). Birth asphyxia, neonatal intensive care admission and need for active resuscitation at birth also occurred significantly less frequently in the dexamethasone group (P value 0.004, 0.009, 0.014 respectively). There were no significant group differences in the incidence of neonatal sepsis, neonatal jaundice, hypoglycemia and feeding difficulties. CONCLUSIONS: Administration of dexamethasone to women at risk for late preterm delivery significantly reduced the rate of neonatal respiratory complications, neonatal intensive care unit admission, and need for active resuscitation at birth. TRIAL REGISTRATION: PACTR ( www.pactr.org ) Registration Number: PACTR202304579281358. The study was retrospectively registered on April 19, 2023.

Implications of maternal vitamin D administration for the neonatal respiratory distress syndrome: A randomized clinical trial.

BACKGROUND: Vitamin D deficiency has been suggested to be a risk factor for neonatal respiratory distress syndrome (RDS). This study aimed to evaluate the effect of 25 (OH) D administrations in pregnant women with findings of preterm labor on the incidence of RDS in their preterm neonates. MATERIALS AND METHODS: A randomized controlled clinical trial was conducted on pregnant mothers with gestational age (GA) of less than 34 weeks at risk of preterm delivery. 175 subjects were randomly assigned into two groups, including intervention (intramuscular injection of 50,000 units of 25(OH) D during 72 hours before delivery) and control (no injections). Serum concentrations of 25(OH) D were measured shortly after birth in both mothers and neonates. Then, clinical and laboratory results of mothers and their offspring were recorded (in a checklist). Short-term outcomes and the need for respiratory support were also assessed. Data were analyzed by independent t-test, Mann-Whitney U test, Fisher's exact test, and chi-square test. RESULTS: Even though gestational age, birth weight, delivery method, and serum vitamin D levels are consistent among both groups, 45% of neonates in the control group and 20% in the intervention group developed respiratory distress syndrome (P = 0.05). The mean 25(OH) D level in neonates was 17.7±10.5 and 19.29±9.94 ng/mL in the intervention and control groups, respectively (P > 0.05). CONCLUSION: A single dose of 50,000 units of intramuscular 25(OH)D in pregnant women at risk of preterm labor can lower the risk of RDS in the infant.

Vaginal Progesterone to Prevent Spontaneous Preterm Birth in Women With a Sonographic Short Cervix: The Story of the PREGNANT Trial.

The PREGNANT trial was a randomized, placebo-controlled, multicenter trial designed to determine the efficacy and safety of vaginal progesterone (VP) to reduce the risk of birth < 33 weeks and of neonatal complications in women with a sonographic short cervix (10 to 20 mm) in the mid-trimester (19 to 23 6/7 wk). Patients allocated to receive VP had a 45% lower rate of preterm birth (8.9% vs 16.1%; relative risk = 0.55; 95% CI: 0.33-0.92). Neonates born to mothers allocated to VP had a 60% reduction in the rate of respiratory distress syndrome. This article reviews the background, design, execution, interpretation, and impact of the PREGNANT Trial.

The use of late preterm antenatal corticosteroids in women with gestational diabetes : a puzzle worth solving.

BACKGROUND: To investigate the association between late preterm antenatal corticosteroid treatment and outcome in late preterm neonates born to mothers with gestational diabetes mellitus, METHODS: All patients with gestational diabetes mellitus who had a late preterm delivery at Etlik Lady Zübeyde Hospital between 2017 and 2021 were included. Women who met the inclusion criteria and were not given antenatal corticosteroid treatment during current pregnancy before 34 0/7 weeks of gestation were divided into two groups according to whether or not they received late preterm antenatal corticosteroid treatment. The two groups were compared in terms of adverse neonatal complications. The main outcomes were composite respiratory outcome and composite neonatal outcome. Logistic regression analysis was used to determine additional potential predictors of neonatal outcome. RESULTS: This retrospective cohort study included a total of 400 participants with gestational diabetes mellitus who had a late preterm delivery within the study period. Of these women, 196 (49%) received late preterm antenatal corticosteroid treatment. Main outcomes showed no difference. Decreasing gestational age at birth was identified as an independent risk factor predicting both composite respiratory outcome and composite neonatal outcome in multivariate logistic regression analysis. CONCLUSIONS: Antenatal corticosteroid treatment at or after 34 0/7 weeks of gestation in women with gestational diabetes mellitus who had a late preterm delivery was not associated with improvement in adverse neonatal outcomes. Decreasing gestational age at birth was the only independent risk factor predicting composite neonatal and composite respiratory outcomes.

Cardiovascular outcomes 50 years after antenatal exposure to betamethasone: Follow-up of a randomised double-blind, placebo-controlled trial.

BACKGROUND: Antenatal corticosteroids for women at risk of preterm birth reduce neonatal morbidity and mortality, but there is limited evidence regarding their effects on long-term health. This study assessed cardiovascular outcomes at 50 years after antenatal exposure to corticosteroids. METHODS AND FINDINGS: We assessed the adult offspring of women who participated in the first randomised, double-blind, placebo-controlled trial of antenatal betamethasone for the prevention of neonatal respiratory distress syndrome (RDS) (1969 to 1974). The first 717 mothers received 2 intramuscular injections of 12 mg betamethasone or placebo 24 h apart and the subsequent 398 received 2 injections of 24 mg betamethasone or equivalent volume of placebo. Follow-up included a health questionnaire and consent to access administrative data sources. The co-primary outcomes were the prevalence of cardiovascular risk factors (any of hypertension, hyperlipidaemia, diabetes mellitus, gestational diabetes mellitus, or prediabetes) and age at first major adverse cardiovascular event (MACE) (cardiovascular death, myocardial infarction, coronary revascularisation, stroke, admission for peripheral vascular disease, and admission for heart failure). Analyses were adjusted for gestational age at entry, sex, and clustering. Of 1,218 infants born to 1,115 mothers, we followed up 424 (46% of survivors; 212 [50%] female) at mean (standard deviation) age 49.3 (1.0) years. There were no differences between those exposed to betamethasone or placebo for cardiovascular risk factors (159/229 [69.4%] versus 131/195 [67.2%]; adjusted relative risk 1.02, 95% confidence interval [CI] [0.89, 1.18;]; p = 0.735) or age at first MACE (adjusted hazard ratio 0.58, 95% CI [0.23, 1.49]; p = 0.261). There were also no differences in the components of these composite outcomes or in any of the other secondary outcomes. Key limitations were follow-up rate and lack of in-person assessments. CONCLUSIONS: There is no evidence that antenatal corticosteroids increase the prevalence of cardiovascular risk factors or incidence of cardiovascular events up to 50 years of age. Established benefits of antenatal corticosteroids are not outweighed by an increase in adult cardiovascular disease.

Antenatal Late Preterm Steroids: The Evolution of the ALPS Trial.

The Antenatal Late Preterm Steroids (ALPS) trial was designed to address respiratory morbidity common in infants born late preterm. The study was published in April, 2016 and, shortly thereafter, changed clinical practice in obstetrics in the United States. The following chapter describes the ALPS trial study design in detail, including the background leading to the trial, the study outcomes, and the initial findings of the long-term follow-up study. The ALPS story would not be complete without Elizabeth Thom, PhD, who died before her time. Her brilliance largely contributed to the design of the ALPS trial.

Late-Preterm Antenatal Steroids for Reduction of Neonatal Respiratory Complications: A Randomized Controlled Trial.

OBJECTIVE: To evaluate the efficacy of antenatal corticosteroids in reducing neonatal respiratory complications when administered to those at risk of preterm delivery between 34 and 36 6/7 weeks of gestation. METHODS: This was a single-center, triple-blind, randomized, placebo-controlled trial in southern India enrolling pregnant participants at risk of preterm delivery between 34 and 36 6/7 weeks of gestation. Computer-generated block randomization was used with participants randomized to either one course of intramuscular betamethasone or placebo. The primary outcome was a composite of treatment for respiratory distress in the neonate, defined as need for oxygen or continuous positive airway pressure or mechanical ventilation for at least 2 hours in the first 72 hours of life. Neonatal secondary outcomes were transient tachypnea of the newborn, respiratory distress syndrome, necrotizing enterocolitis, sepsis, hyperbilirubinemia, hypoglycemia, stillbirth, and early neonatal death; maternal secondary outcomes were chorioamnionitis, postpartum hemorrhage, puerperal fever, and length of hospitalization. All analyses were based on intention to treat. A sample size of 1,200 was planned with 80% power to detect a 30% reduction in rates of respiratory distress. After a planned interim analysis, enrollment was stopped for futility. RESULTS: From March 2020 to August 2022, 847 participants were recruited, with 423 participants randomized to betamethasone and 424 participants randomized to placebo. There were 22 individuals lost to follow-up. There was no statistically significant difference in the primary outcome (betamethasone 4.9% vs placebo 4.8%, relative risk 1.03, 95% CI, 0.57-1.84, number needed to treat 786). There were no statistically significant differences in secondary neonatal or maternal outcomes. CONCLUSION: Betamethasone administered in the late-preterm period to those at risk for preterm delivery did not reduce the need for treatment of neonatal respiratory distress. CLINICAL TRIAL REGISTRATION: Clinical Trials Registry of India, CTRI/2019/09/021321.

Antenatal corticosteroid administration is associated with lower risk of severe ROP in preterm twin infants.

INTRODUCTION: Robust evidence revealed the impact of antenatal corticosteroid (ACS) administration on lower mortality and short-term neonatal outcomes in singleton preterm infants. We aimed to investigate the impact of ACS therapy on morbidity and mortality in preterm twin infants. METHODS: We conducted this retrospective single-center study from to the records of twin babies of 24-30 weeks of gestation admitted to the neonatal intensive care unit. The study population was grouped based on the exposure to ACS 1-7 days before birth as received or not. Groups were compared regarding in-hospital mortality and neonatal outcomes. RESULTS: Data from 160 twin infants were analyzed. Of those, 102 (64 %) were administered ACS. The median (IQR) gestational age and birth weight of the whole cohort were 28 (27-29) weeks and 1060 (900-1240) g, respectively. ACS administration was associated with a significant decline in respiratory distress syndrome (RDS), requirement ≥2 doses of surfactant, severe intraventricular hemorrhage (IVH), early-onset sepsis (EOS), and retinopathy of prematurity (ROP) requiring treatment (p < 0.05). Logistic regression analysis revealed that gestational age (OR 0.29 95 % CI 0.14-0.62; p = 0.001), ACS administration (OR 0.14 95 % CI 0.03-0.85; p = 0.032), and time to achieve full enteral feeding (OR 1.16 95 % CI 1.03-1.31; p = 0.019) were independently associated with the risk of severe ROP. CONCLUSION: The reduction in the risk of severe ROP besides RDS, severe IVH, and EOS among preterm twins who received ACS was remarkable in our study similar to the trials conducted in preterm singletons. However, large-scale prospective observational studies are required to reveal the efficacy of ACS in preterm twins.

Antenatal corticosteroids and newborn respiratory outcomes in twins: A regression discontinuity study.

OBJECTIVE: To estimate the effect of antenatal corticosteroids on newborn respiratory morbidity in twins. DESIGN: Regression discontinuity applied to population-based birth registry data. SETTING: British Columbia, Canada, 2008-2018. POPULATION: Twin pregnancies admitted for birth between 31+0 and 36+6 weeks of gestation. METHODS: During our study period, Canadian clinical practice guidelines recommended antenatal corticosteroid administration for imminent preterm birth up to 33+6 weeks. We used a logistic model to compare the predicted risks of our outcomes among pregnancies admitted for birth immediately before this clinical cut-point (higher probability of exposure to antenatal corticosteroids) versus immediately after it (lower probability). MAIN OUTCOME MEASURES: Our primary outcome was a composite of newborn respiratory distress or in-hospital death. Our secondary outcome was a composite of newborn respiratory intervention or in-hospital death. RESULTS: Among 2524 pregnancies (5035 liveborn twins), 47% of admissions before 34+0 weeks of gestation were exposed to antenatal corticosteroids but only 4.2% of admissions after this cut-point were exposed. The risk of newborn respiratory distress or in-hospital mortality increased abruptly at 34+0 weeks, corresponding to a protective effect of treatment (risk ratio [RR] 0.69, 95% CI 0.53-0.90; risk difference [RD] -12 cases per 100 births, 95% CI -20 to -4.1). There was no clear evidence for or against an effect on newborn respiratory intervention or in-hospital death (RR 0.89, 95% CI 0.70-1.13; RD -4.2 per 100, 95% CI -13 to +4.2). CONCLUSIONS: Our findings provide evidence for the effectiveness of antenatal corticosteroids in preventing adverse newborn respiratory outcomes in twins.

Laryngeal mask airway surfactant administration for prevention of morbidity and mortality in preterm infants with or at risk of respiratory distress syndrome.

BACKGROUND: Laryngeal mask airway surfactant administration (S-LMA) has the potential benefit of surfactant administration whilst avoiding endotracheal intubation and ventilation, ventilator-induced lung injury and bronchopulmonary dysplasia (BPD). OBJECTIVES: To evaluate the benefits and harms of S-LMA either as prophylaxis or treatment (rescue) compared to placebo, no treatment, or intratracheal surfactant administration via an endotracheal tube (ETT) with the intent to rapidly extubate (InSurE) or extubate at standard criteria (S-ETT) or via other less-invasive surfactant administration (LISA) methods on morbidity and mortality in preterm infants with or at risk of respiratory distress syndrome (RDS). SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, CINAHL, and three trial registries in December 2022. SELECTION CRITERIA: Randomised controlled trials (RCTs), cluster- or quasi-RCTs of S-LMA compared to placebo, no treatment, or other routes of administration (nebulised, pharyngeal instillation of surfactant before the first breath, thin endotracheal catheter surfactant administration or intratracheal surfactant instillation) on morbidity and mortality in preterm infants at risk of RDS. We considered published, unpublished and ongoing trials. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for inclusion and extracted data. We used GRADE to assess the certainty of the evidence. MAIN RESULTS: We included eight trials (seven new to this update) recruiting 510 newborns. Five trials (333 infants) compared S-LMA with surfactant administration via ETT with InSurE. One trial (48 infants) compared S-LMA with surfactant administration via ETT with S-ETT, and two trials (129 infants) compared S-LMA with no surfactant administration. We found no studies comparing S-LMA with LISA techniques or prophylactic or early S-LMA. S-LMA versus surfactant administration via InSurE S-LMA may have little or no effect on the composite outcome of death or BPD at 36 weeks' postmenstrual age (risk ratio (RR) 1.50, 95% confidence interval (CI) 0.27 to 8.34, I 2 = not applicable (NA) as 1 study had 0 events; risk difference (RD) 0.02, 95% CI -0.07 to 0.10; I 2 = 0%; 2 studies, 110 infants; low-certainty evidence). There may be a reduction in the need for mechanical ventilation at any time (RR 0.53, 95% CI 0.36 to 0.78; I 2 = 27%; RD -0.14, 95% CI -0.22 to -0.06, I 2 = 89%; number needed to treat for an additional beneficial outcome (NNTB) 7, 95% CI 5 to 17; 5 studies, 333 infants; low-certainty evidence). However, this was limited to four studies (236 infants) using analgesia or sedation for the InSurE group. There was little or no difference for air leak during first hospitalisation (RR 1.39, 95% CI 0.65 to 2.98; I 2 = 0%; 5 studies, 333 infants (based on 3 studies as 2 studies had 0 events); low-certainty evidence); BPD among survivors to 36 weeks' PMA (RR 1.28, 95% CI 0.47 to 3.52; I 2 = 0%; 4 studies, 264 infants (based on 3 studies as 1 study had 0 events); low-certainty evidence); or death (all causes) during the first hospitalisation (RR 0.28, 95% CI 0.01 to 6.60; I 2 = NA as 2 studies had 0 events; 3 studies, 203 infants; low-certainty evidence). Neurosensory disability was not reported. Intraventricular haemorrhage ( IVH) grades III and IV were reported among the study groups (1 study, 50 infants). S-LMA versus surfactant administration via S-ETT No study reported death or BPD at 36 weeks' PMA. S-LMA may reduce the use of mechanical ventilation at any time compared with S-ETT (RR 0.47, 95% CI 0.31 to 0.71; RD -0.54, 95% CI -0.74 to -0.34; NNTB 2, 95% CI 2 to 3; 1 study, 48 infants; low-certainty evidence). We are very uncertain whether S-LMA compared with S-ETT reduces air leak during first hospitalisation (RR 2.56, 95% CI 0.11 to 59.75), IVH grade III or IV (RR 2.56, 95% CI 0.11 to 59.75) and death (all causes) during the first hospitalisation (RR 0.17, 95% CI 0.01 to 3.37) (1 study, 48 infants; very low-certainty evidence). No study reported BPD to 36 weeks' PMA or neurosensory disability. S-LMA versus no surfactant administration Rescue surfactant could be used in both groups. There may be little or no difference in death or BPD at 36 weeks (RR 1.65, 95% CI 0.85 to 3.22; I 2 = 58%; RD 0.08, 95% CI -0.03 to 0.19; I 2 = 0%; 2 studies, 129 infants; low-certainty evidence). There was probably a reduction in the need for mechanical ventilation at any time with S-LMA compared with nasal continuous positive airway pressure without surfactant (RR 0.57, 95% CI 0.38 to 0.85; I 2 = 0%; RD -0.24, 95% CI -0.40 to -0.08; I 2 = 0%; NNTB 4, 95% CI 3 to 13; 2 studies, 129 infants; moderate-certainty evidence). There was little or no difference in air leak during first hospitalisation (RR 0.65, 95% CI 0.23 to 1.88; I 2 = 0%; 2 studies, 129 infants; low-certainty evidence) or BPD to 36 weeks' PMA (RR 1.65, 95% CI 0.85 to 3.22; I 2 = 58%; 2 studies, 129 infants; low-certainty evidence). There were no events in either group for death during the first hospitalisation (1 study, 103 infants) or IVH grade III and IV (1 study, 103 infants). No study reported neurosensory disability. AUTHORS' CONCLUSIONS: In preterm infants less than 36 weeks' PMA, rescue S-LMA may have little or no effect on the composite outcome of death or BPD at 36 weeks' PMA. However, it may reduce the need for mechanical ventilation at any time. This benefit is limited to trials reporting the use of analgesia or sedation in the InSurE and S-ETT groups. There is low- to very-low certainty evidence for no or little difference in neonatal morbidities and mortality. Long-term outcomes are largely unreported. In preterm infants less than 32 weeks' PMA or less than 1500 g, there are insufficient data to support or refute the use of S-LMA in clinical practice. Adequately powered trials are required to determine the effect of S-LMA for prevention or early treatment of RDS in extremely preterm infants. S-LMA use should be limited to clinical trials in this group of infants.

A comparison of 2 doses of antenatal dexamethasone for the prevention of respiratory distress syndrome: an open-label, noninferiority, pragmatic randomized trial.

BACKGROUND: Antenatal corticosteroids have been used for the prevention of respiratory complications, intraventricular hemorrhage, necrotizing enterocolitis, and other adverse neonatal outcomes for over 50 years, with limited evidence about their optimal doses. Higher steroid doses or frequencies of antenatal corticosteroids in preterm newborns pose adverse effects such as prolonged adrenal suppression, negative effects on fetal programming and metabolism, and increased risks of neurodevelopmental and neuropsychological impairments. Conversely, lower doses of antenatal corticosteroids may be an effective alternative to induce fetal lung maturation with less risk to the fetus. Late preterm births represent the largest population of all preterm neonates, with a respiratory distress syndrome risk of 8.83%. Therefore, determining the optimal antenatal corticosteroid dosage is of particular importance for this population. OBJECTIVE: This study aimed to compare the efficacy of 5-mg and 6-mg dexamethasone in preventing neonatal respiratory distress syndrome in women with preterm births at 320 to 366 weeks of gestation. STUDY DESIGN: This was an open-label, randomized, controlled, noninferiority trial. Singleton pregnant women (n=370) at 320 to 366 weeks of gestation with spontaneous preterm labor or preterm premature rupture of membranes were enrolled. They were randomly assigned (1:1) to a 5-mg or 6-mg dexamethasone group. Dexamethasone was administered intramuscularly every 12 hours for 4 doses or until delivery. The primary outcome was the reduction in neonatal respiratory distress syndrome cases, whereas the secondary outcomes were any adverse maternal or neonatal events. RESULTS: Between December 2020 and April 2022, 370 eligible women, anticipating deliveries within the gestational range of 32 0/7 to 36 6/7 weeks, willingly participated in the study. They were evenly split, with 185 women assigned to the 5-mg group and 185 to the 6-mg group. The study revealed that the demographic profiles of the participants in the 2 groups were remarkably similar, with no statistically significant disparities (P>.05). It is noteworthy that most of these women gave birth after 34 weeks of gestation. Despite a substantial proportion not completing the full course of steroid treatment, the 5-mg dose exhibited noninferiority compared with the 6-mg dose of dexamethasone, as indicated by a modest proportional difference of 0.5% (95% confidence interval, -2.8 to 43.9). Neonatal respiratory distress syndrome occurred in a relatively low percentage of newborns in both groups, affecting 2.2% in the 5-mg group and 1.6% in the 6-mg group. Notably, the risk difference of 0.6% fell comfortably within the predefined noninferiority threshold of 10%. CONCLUSION: Our study suggests that a 5-mg dexamethasone dose is noninferior to a standard 6-mg dose in preventing neonatal respiratory distress syndrome in preterm births.

Prophylactic Oropharyngeal Surfactant for Preterm Newborns at Birth: A Randomized Clinical Trial.

Importance: Preterm newborns at risk of respiratory distress syndrome are supported with continuous positive airway pressure (CPAP). Many newborns worsen despite CPAP and are intubated for surfactant administration, an effective therapy for treatment of respiratory distress syndrome. Endotracheal intubation is associated with adverse effects. Pharyngeal administration of surfactant to preterm animals and humans has been reported as an alternative. Objective: To assess whether giving prophylactic oropharyngeal surfactant to preterm newborns at birth would reduce the rate of intubation for respiratory failure. Design, Setting, and Participants: This unblinded, parallel-group randomized clinical trial (Prophylactic Oropharyngeal Surfactant for Preterm Infants [POPART]) was conducted from December 17, 2017, to September 11, 2020, at 9 tertiary neonatal intensive care units in 6 European countries. Newborns born before 29 weeks of gestation without severe congenital anomalies, for whom intensive care was planned, were eligible for inclusion. The data were analyzed from July 27, 2022, to June 20, 2023. Intervention: Newborns were randomly assigned to receive oropharyngeal surfactant at birth in addition to CPAP or CPAP alone. Randomization was stratified by center and gestational age (GA). Main Outcomes and Measures: The primary outcome was intubation in the delivery room for bradycardia and/or apnea or in the neonatal intensive care unit for prespecified respiratory failure criteria within 120 hours of birth. Caregivers were not masked to group assignment. Results: Among 251 participants (mean [SD] GA, 26 [1.5] weeks) who were well matched at study entry, 126 (69 [54.8%] male) with a mean (SD) birth weight of 858 (261) grams were assigned to the oropharyngeal surfactant group, and 125 (63 [50.4%] male) with a mean (SD) birth weight of 829 (253) grams were assigned to the control group. The proportion of newborns intubated within 120 hours was not different between the groups (80 [63.5%) in the oropharyngeal surfactant group and 81 [64.8%] in the control group; relative risk, 0.98 [95% CI, 0.81-1.18]). More newborns assigned to the oropharyngeal surfactant group were diagnosed with and treated for pneumothorax (21 [16.6%] vs 8 [6.4%]; P = .04). Conclusions and Relevance: This randomized clinical trial found that administration of prophylactic oropharyngeal surfactant to newborns born before 29 weeks' GA did not reduce the rate of intubation in the first 120 hours of life. These findings suggest that administration of surfactant into the oropharynx immediately after birth in addition to CPAP should not be routinely used. Trial Registration: EudraCT: 2016-004198-41.

Surfactant as a drug carrier.

Drug delivery using a surfactant vehicle has the potential to prevent systemic side effects by delivering therapeutic agents directly to the respiratory system. The inherent chemical properties of surfactant allows it to readily distribute throughout the respiratory system. Therapeutic agents delivered by surfactant can primarily confer additional benefits but have potential to improve surfactant function. It is critically important that additional agents do not interefere with the innate surface tension lowering function of surfactant. Systemic evaluation through benchtop, translational and human trials are required to translate this potential technique into clinical practice.

Antenatal corticosteroid therapy, delivery intervals and perinatal mortality in low-resource settings.

BACKGROUND: Uncertainty exists regarding the ideal interval between the administration of antenatal corticosteroids (ACS) and delivery. The study's objective was to assess the risks of perinatal mortality and respiratory distress syndrome (RDS) among preterm neonates whose mothers gave birth within 48 h of the administration of ACS and those whose mothers gave birth between 48 h and 7 days. METHODS: The study design was a secondary analysis of data from an observational prospective chart review study that was carried out in Tanzania in 2020. Preterm infants born to mothers who got at least one dose of ACS between 28 and 34 weeks of pregnancy were included. RESULTS: A total of 346 preterm neonates (294 singletons and 52 twins) were exposed to ACS. Compared to infants born 48 h following the first dose of ACS, those exposed to the drug between 48 h and 7 days had significantly decreased rates of perinatal mortality and RDS. Multivariable analysis revealed that infants exposed ACS between 48 h and 7 days prior to delivery had lower risk of perinatal mortality (aRR 0.30, 95% CI 0.14-0.66) and RDS (aRR 0.27, 95% CI 0.14-0.52). CONCLUSION: The first dose of ACS given between 48 h and 7 days before delivery was associated with a lower risk of perinatal mortality and RDS than when the first dose was given <48 h before delivery. To improve neonatal outcomes, healthcare providers should consider administering ACS to mothers at the appropriate time.

Preterm infants exposed to antenatal corticosteroids (ACS) have lower rates of perinatal mortality and morbidity. Uncertainty exists regarding the ideal interval between the administration of ACS and delivery. We conducted a secondary analysis of data from a study that included preterm infants born in four hospitals in Tanzania. We investigated whether there were differences in perinatal mortality and respiratory distress syndrome between preterm neonates whose mothers delivered within 48 h of receiving a partial course of ACS and those whose mothers delivered between 48 h and 7 days after a full course of ACS therapy. Participants were the preterm infants of women who received ACS between 28 and 34 weeks of gestation. Neonates exposed to ACS between 48 h and 7 days prior to delivery had significantly lower risks of perinatal mortality and respiratory distress syndrome compared to infants who were delivered <48 h after ACS administration. This finding highlights the importance of optimizing the timing of ACS administration to maximize its potential benefits and minimize risks to preterm neonates. To improve neonatal outcomes, healthcare providers should consider administering ACS to mothers at the appropriate time.

Surfactant therapy guided by tests for lung maturity in preterm infants at risk of respiratory distress syndrome.

BACKGROUND: Administration of various exogenous surfactant preparations has been shown to decrease lung injury and pneumothorax and improve survival in very preterm infants with respiratory distress syndrome (RDS). There is no consensus on the threshold for surfactant administration, to allow timely intervention and avoid over-treatment, also considering the invasiveness of the procedure and its cost. Rapid tests for lung maturity, which include the click test, lamellar body counts and stable microbubble test, might guide the identification of those infants needing surfactant administration. OBJECTIVES: To assess the effects of surfactant treatment guided by rapid tests for surfactant deficiency in preterm infants at risk for or having RDS. Comparison 1: In preterm infants at risk for RDS, does surfactant treatment guided by rapid tests for surfactant deficiency compared to prophylactic surfactant administration to all high-risk infants minimize the need for surfactant treatment and prevent bronchopulmonary dysplasia and mortality? Comparison 2: In preterm infants who require early respiratory support, does surfactant treatment guided by rapid tests for surfactant deficiency compared to surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria minimize the need for surfactant treatment and prevent bronchopulmonary dysplasia and mortality? SEARCH METHODS: We searched in October 2022 CENTRAL, PubMed, Embase and three additional trial registries. We also screened the reference lists of included studies and related systematic reviews for studies not identified by the database searches. SELECTION CRITERIA: We included randomized controlled trials (RCTs) and quasi-RCTs evaluating rapid tests after birth for surfactant deficiency in infants at high risk of RDS or requiring respiratory support. We specified two comparisons: 1)surfactant treatment guided by rapid tests for surfactant deficiency versus prophylactic surfactant administration to all high-risk infants in extremely preterm (less than 28 weeks' gestation) and very preterm (28 to 32 weeks' gestation); 2)surfactant treatment guided by rapid tests for surfactant deficiency versus surfactant therapy provided to preterm infants (less than 37 weeks' gestation) with RDS diagnosed on clinical and radiologic criteria. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. We used the fixed-effect model with risk ratio (RR) and risk difference (RD), with their 95% confidence intervals (CIs) for dichotomous data. Our primary outcomes were: neonatal mortality, mortality prior to hospital discharge, bronchopulmonary dysplasia and the composite outcome bronchopulmonary dysplasia or mortality. We used GRADE to assess the certainty of evidence. MAIN RESULTS: We included three RCTs enrolling 562 newborn infants in this review. No studies compared surfactant treatment guided by rapid tests for surfactant deficiency versus prophylactic surfactant administration to all high-risk infants. Comparing surfactant therapy guided by rapid tests for surfactant deficiency versus surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria. No studies reported neonatal mortality. Compared with surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria, the evidence is very uncertain about the effect of surfactant treatment guided by rapid tests for surfactant deficiency on mortality prior to hospital discharge: RR 1.25, 95% CI 0.65 to 2.41, RD 0.01, 95% CI -0.03 to 0.05, 562 participants, 3 studies; I² for RR and RD = 75% and 43%, respectively; very low-certainty evidence. Surfactant treatment guided by rapid tests for surfactant deficiency may result in little to no difference in bronchopulmonary dysplasia: RR 0.90, 95% CI 0.61 to 1.32, RD -0.02, 95% CI -0.08 to 0.04, 562 participants, 3 studies; I² for RR and RD = 0%; low-certainty evidence. No studies reported the composite outcome bronchopulmonary dysplasia or mortality. Surfactant treatment guided by rapid tests for surfactant deficiency may result in little to no difference in surfactant utilization (RR 0.97, 95% CI 0.85 to 1.11, RD -0.02, 95% CI -0.10 to 0.06, 562 participants, 3 studies, I² for RR and RD = 63% and 65%, respectively, low-certainty evidence), and any pneumothorax (RR 0.53, 95% CI 0.15 to 1.92, RD -0.01, 95% CI -0.04 to 0.01, 506 participants, 2 studies, I² for RR and RD = 0%, low-certainty evidence) compared with surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria. No studies reported moderate to severe neurodevelopmental impairment. We identified two large ongoing RCTs. AUTHORS' CONCLUSIONS: No studies compared surfactant treatment guided by rapid tests for surfactant deficiency to prophylactic surfactant administration to all high-risk infants. Low to very low-certainty evidence from three studies is available on surfactant therapy guided by rapid tests for surfactant deficiency versus surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria. No studies reported neonatal mortality, the composite outcome 'bronchopulmonary dysplasia or mortality', or neurodevelopmental outcomes. Compared with surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria, the evidence is very uncertain about the effect of surfactant treatment guided by rapid tests for surfactant deficiency on mortality prior to hospital discharge. Surfactant treatment guided by rapid tests for surfactant deficiency may result in little to no difference in bronchopulmonary dysplasia, surfactant utilization and any pneumothorax. The findings of the two large ongoing trials identified in this review are likely to have an important impact on establishing the effects of surfactant treatment guided by rapid tests for surfactant deficiency in preterm infants.

Surfactant delivery strategies to prevent bronchopulmonary dysplasia.

Bronchopulmonary dysplasia (BPD) is one of the most devastating morbidities of preterm infants. Antenatal factors like growth restriction and inflammation are risk factors for its development. Use of oxygen and positive pressure ventilation, which are often necessary to treat respiratory distress syndrome (RDS), increase the risk for development of BPD. Continuous positive airway pressure (CPAP) as primary respiratory support allows for avoidance of positive pressure ventilation in many cases but may lead to a delay of surfactant administration which is a proven therapy for RDS. Several alternative surfactant delivery strategies, including nebulization of surfactant, pharyngeal instillation of surfactant, delivery of surfactant via supraglottic airway device or surfactant delivery via a thin endotracheal catheter have been described which allow for the benefit of surfactant therapy while on CPAP. This review reports available data and discusses the existing evidence of their value in preventing BPD as well as further research directions.

Post Antenatal Late Preterm Steroids trial: interrupted time series analysis of respiratory outcomes in twin and pregestational diabetes.

BACKGROUND: The Antenatal Late Preterm Steroids trial found that corticosteroid administration decreased respiratory complications by 20% among late preterm singleton deliveries. After the Antenatal Late Preterm Steroids trial, corticosteroid administration increased by 76% among twin pregnancies and 113% among singleton pregnancies complicated by pregestational diabetes mellitus compared with expected rates based on the pre-Antenatal Late Preterm Steroids trial trend. However, the effect of corticosteroids on twin pregnancies and pregnancies complicated by pregestational diabetes mellitus is not well studied, as the Antenatal Late Preterm Steroids trial excluded twin pregnancies and pregnancies complicated by pregestational diabetes mellitus. OBJECTIVE: This study aimed to examine the change in the incidence rate of immediate assisted ventilation use and ventilation use for more than 6 hours among 2 populations after the dissemination of the Antenatal Late Preterm Steroids trial at the population level. STUDY DESIGN: This study was a retrospective analysis of publicly available US birth certificate data. The study period was from August 1, 2014, to April 30, 2018. The dissemination period of the Antenatal Late Preterm Steroids trial was from February 2016 to October 2016. Population-based interrupted time series analyses were performed for 2 target populations: (1) twin pregnancies not complicated by pregestational diabetes mellitus and (2) singleton pregnancies complicated by pregestational diabetes mellitus. For both target populations, analyses were limited to individuals who delivered nonanomalous live neonates between 34 0/7 and 36 6/7 weeks of gestation (vaginal or cesarean delivery). As a sensitivity analysis, a total of 23 placebo tests were conducted before (5 tests) and after (18 tests) the dissemination period. RESULTS: For the analysis of late preterm twin deliveries, 191,374 individuals without pregestational diabetes mellitus were identified. For the analysis of late preterm singleton pregnancy with pregestational diabetes mellitus, 21,395 individuals were identified. After the dissemination period, the incidence rate of immediate assisted ventilation use for late preterm twin deliveries was significantly lower than the expected value based on the pre-Antenatal Late Preterm Steroids trial trend (11.6% observed vs 13.0% expected; adjusted incidence rate ratio, 0.87; 95% confidence interval, 0.78-0.97). The incidence rate of ventilation use for more than 6 hours among late preterm twin deliveries did not change significantly after the dissemination of the Antenatal Late Preterm Steroids trial. A significant increase in the incidence rate of immediate assisted ventilation use and ventilation use for more than 6 hours was found among singleton pregnancies with pregestational diabetes mellitus. However, the results of placebo tests suggested that the increase in incidence was not necessarily due to the dissemination period of the Antenatal Late Preterm Steroids trial. CONCLUSION: The dissemination of the Antenatal Late Preterm Steroids trial was associated with decreased incidence of immediate assisted ventilation use, but no change in ventilation use for more than 6 hours, among late preterm twin deliveries in the United States. In contrast, the incidence of neonatal respiratory outcomes among singleton deliveries with pregestational diabetes mellitus did not decrease after the dissemination of the Antenatal Late Preterm Steroids trial.

One vs 2 courses of antenatal corticosteroids in pregnancies at risk of preterm birth: a secondary analysis of the MACS trial.

BACKGROUND: Birth is unpredictable and many patients who receive antenatal corticosteroids for preterm birth remain pregnant. Some professional societies recommend rescue antenatal corticosteroids for those who remain pregnant ≥14 days following the initial course. OBJECTIVE: This study aimed to explore a single vs a second course of antenatal corticosteroids in terms of severe neonatal morbidity and mortality. STUDY DESIGN: This is a secondary analysis of the Multiple Courses of Antenatal Corticosteroids for Preterm Birth (MACS) trial. The MACS study was a randomized clinical trial conducted in 80 centers in 20 different countries from 2001 to 2006. Participants who received only 1 course of intervention (ie, either a second course of antenatal corticosteroids or placebo) were included in this study. The primary outcome was a composite of stillbirth, neonatal mortality in the first 28 days of life or before discharge, severe respiratory distress syndrome, bronchopulmonary dysplasia, intraventricular hemorrhage stage III and IV, periventricular leukomalacia, and necrotizing enterocolitis. Two subgroup analyses were planned to address the effect of a second course of antenatal corticosteroids on infants born before 32 weeks or within 7 days from the intervention. Moreover, a sensitivity analysis was performed to assess the effect of intervention on singleton pregnancies. Baseline characteristics were compared between the groups using chi-square and Student t tests. Multivariable regression analysis was performed to adjust for confounding variables. RESULTS: There were 385 and 365 participants included in the antenatal corticosteroid and placebo groups, respectively. The composite primary outcome occurred in 24% and 20% of participants in the antenatal corticosteroid and placebo groups, respectively (adjusted odds ratio, 1.09; 95% confidence interval, 0.76-1.57). Moreover, severe respiratory distress syndrome rate was similar between the 2 groups (adjusted odds ratio, 0.98; 95% confidence interval, 0.65-1.48). Newborns exposed to antenatal corticosteroids were more likely to be small for gestational age (14.9% vs 10.6%; adjusted odds ratio, 1.63; 95% confidence interval, 1.07-2.47). These findings remained true among singleton pregnancies for the primary composite outcome and birthweight <10th percentile (adjusted odds ratio, 1.29 [0.82-2.01]; and adjusted odds ratio, 1.74 [1.06-2.87]; respectively). Subgroup analyses of infants born before 32 weeks or within 7 days from the intervention did not show any benefits in terms of the composite primary outcome with antenatal corticosteroids vs placebo (50.5% vs 41.8% [adjusted odds ratio, 1.16; 95% confidence interval, 0.78-1.72]; and 42.3% vs 37.1% [adjusted odds ratio, 1.02; 95% confidence interval, 0.67-1.57]; respectively). CONCLUSION: Neonatal mortality and severe morbidities, including severe respiratory distress syndrome, were not improved by a second course of antenatal corticosteroids. Policy makers need to be thoughtful when recommending a second course of antenatal corticosteroids and consider whether not only short-term but also long-term benefits can be gained from such administration.