Lung UltrasouNd Guided surfactant therapy in preterm infants: an international multicenter randomized control trial (LUNG study).

BACKGROUND: The management of respiratory distress syndrome (RDS) in premature newborns is based on different types of non-invasive respiratory support and on surfactant replacement therapy (SRT) to avoid mechanical ventilation as it may eventually result in lung damage. European guidelines currently recommend SRT only when the fraction of inspired oxygen (FiO2) exceeds 0.30. The literature describes that early SRT decreases the risk of bronchopulmonary dysplasia (BPD) and mortality. Lung ultrasound score (LUS) in preterm infants affected by RDS has proven to be able to predict the need for SRT and different single-center studies have shown that LUS may increase the proportion of infants that received early SRT. Therefore, the aim of this study is to determine if the use of LUS as a decision tool for SRT in preterm infants affected by RDS allows for the reduction of the incidence of BPD or death in the study group. METHODS/DESIGN: In this study, 668 spontaneously-breathing preterm infants, born at 25+0 to 29+6 weeks' gestation, in nasal continuous positive airway pressure (nCPAP) will be randomized to receive SRT only when the FiO2 cut-off exceeds 0.3 (control group) or if the LUS score is higher than 8 or the FiO2 requirements exceed 0.3 (study group) (334 infants per arm). The primary outcome will be the difference in proportion of infants with BPD or death in the study group managed compared to the control group. DISCUSSION: Based on previous published studies, it seems that LUS may decrease the time to administer surfactant therapy. It is known that early surfactant administration decreases BPD and mortality. Therefore, there is rationale for hypothesizing a reduction in BPD or death in the group of patients in which the decision to administer exogenous surfactant is based on lung ultrasound scores. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT05198375 . Registered on 20 January 2022.

Can lung ultrasound score accurately predict surfactant replacement? A systematic review and meta-analysis of diagnostic test studies.

BACKGROUND: Clinical and radiographic criteria are traditionally used to determine the need for surfactant therapy in preterm infants. Lung ultrasound is a bedside test that offers a rapid, radiation-free, alternative to this approach. OBJECTIVE: To conduct a systematic review and meta-analysis to determine the accuracy of a lung ultrasound score (LUS) in identifying infants who would receive at least one surfactant dose. Secondary aims were to evaluate the predictive accuracy for ≥2 doses and the accuracy of a different image classification system based on three lung ultrasound profiles. METHODS: PubMed, SCOPUS, Biomed Central, and the Cochrane library between January 2011 and December 2021 were searched. Full articles enrolling preterm neonates who underwent lung ultrasound to predict surfactant administration were assessed and analyzed following Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) and QUADAS-2 guidelines. RESULTS: Seven prospective studies recruiting 697 infants met the inclusion criteria. Risk of bias was generally low. Oxygen requirement, clinical and radiographic signs of respiratory distress syndrome were used as reference standards for surfactant replacement. The summary receiver operator characteristic (sROC) curve for LUS predicting first surfactant dose showed an area under the curve (AUC) = 0.88 (95% confidence interval [CI]: 0.82-0.91); optimal specificity and sensitivity (Youden index) were 0.83 and 0.81 respectively. Pooled estimates of sensitivity, specificity, diagnostic odds ratio, negative predictive value, and positive predictive value for LUS predicting the first surfactant dose were 0.89 (0.82-0.95), 0.86 (0.78-0.95), 3.78 (3.05-4.50), 0.92 (0.87-0.97), 0.79 (0.65-0.92). The sROC curve for the accuracy of Type 1 lung profile in predicting first surfactant dose showed an AUC of 0.88; optimal specificity and sensitivity were both 0.86. Two studies addressing the predictive accuracy of LUS for ≥2 surfactant doses had high heterogeneity and were unsuitable to combine in a meta-analysis. DISCUSSION: Despite current significant variation in LUS thresholds, lung ultrasound is highly predictive of the need for early surfactant replacement. This evidence was derived from studies with homogeneous patient characteristics and low risk of bias.

Lung ultrasound in Italian neonatal intensive care units: A national survey.

INTRODUCTION: Lung ultrasound (LU) is a noninvasive, bedside imaging technique that is attracting growing interest in the evaluation of neonatal respiratory diseases. We conducted a nationwide survey of LU usage in Italian neonatal intensive care units (NICUs). METHODS: A structured questionnaire was developed and sent online to 114 Italian NICUs from June to September 2021. RESULTS: The response rate was 79%. In the past 4 years (range: 2-6), LU has been adopted in 82% of Italian NICUs. It is the first-choice diagnostic test in 23% of the centers surveyed. The main LU diagnostic applications reported were: pneumothorax (95%), respiratory distress syndrome (89%), transient tachypnea of the newborn (89%), plural effusion (88%), atelectasis (66%), pneumonia (64%), bronchopulmonary dysplasia (43%), congenital pulmonary airway malformation (41%), and congenital diaphragmatic hernia (34%). Thirty percent of participating centers calculated LU score routinely, but only seven units used it to predict the need for surfactant replacement. Sixty-six percent of respondents learned the LU technique via a self-training process, while 34% of them visited an expert in the field for one-to-one tuition. CONCLUSIONS: LU has a widespread use in Italian NICUs. However, the use of LU is extremely heterogeneous among centers. There is an urgent need to ensure standardization of clinical practice guidelines and to design and implement a formalized and accredited training program.

Lung ultrasound scores in neonatal clinical practice: A narrative review of the literature.

Lung ultrasound (LU) has in recent years increasingly been used as a point-of-care method. Initially, LU was used as a so-called descriptive diagnostic method for neonatal respiratory diseases. Instead, this review article focuses on the use of LU as a "functional" tool using classification of findings in patterns or using semiquantitative scores. We review and describe the evidence that led to the implementation of LU in predicting the need for surfactant replacement therapy in preterm infants and in the identification of newborns at risk of developing bronchopulmonary dysplasia. LU appears to be a very promising method for the future of clinical management of newborns in both acute and chronic phases of pulmonary pathologies related to prematurity. However, further studies are needed to define its role before full implementation.

Reducing post-extubation failure rates in very preterm infants: is BiPAP better than CPAP?

BACKGROUND AND AIM: Continuous positive airway pressure (CPAP) is currently used in neonates after mechanical ventilation though it may occasionally be associated with air leaks syndromes or it may fail to support the baby. The pressure difference offered by bilevel continuous positive distending pressure (BiPAP) respect to CPAP may be an advantage to the spontaneously breathing patient. In this study, we compared the efficacy of CPAP and BiPAP in the firstweek post-extubation in a series of very preterm infants. METHODS: Inborn neonates less than 30 weeks of gestational age who were intubated shortly after birth from January 2011 to December 2017 were enrolled in a retrospective study. The attending clinician assessed the patients for non-invasive respiratory support readiness and allocated them to CPAP (PEEP 4-6 cmH2O) or BiPAP (PEEP 4-5 cmH2O, rate 10-40; Thigh 0.7-1.2; upper-pressure level 8-10 cmH2O). Both techniques were compared for preventing extubation failure within 7 days from extubation as defined per local protocol (primary outcome). Secondary outcomes were: definitive failure of extubation, pneumothorax during non-invasive respiratory support, periventricular leukomalacia, bronchopulmonary dysplasia, sepsis, patent ductus arteriosus and retinopathy of prematurity at discharge. RESULTS: We enrolled 134 neonates; the CPAP group included 89 babies while 45 received BiPAP. Patients did not differ for their general characteristics (EG, antenatal steroids, incidence of SGA, maternal hypertension, surfactant replacement therapy). Short term extubation failure was significantly higher in the former group (23/89 in CPAP vs 5/45 in BiPAP; p = .005). No infant developed air leak syndrome. Secondary outcomes were comparable between groups. Multivariate analysis showed that on the whole population the extubation failure was correlated to the insurgence of late-onset sepsis. CONCLUSION: BiPAP safely reduced early extubation failure compared to CPAP in our cohort of very preterm neonates within 7 days from extubation.

Lung Ultrasound Score Progress in Neonatal Respiratory Distress Syndrome.

BACKGROUND AND OBJECTIVES: The utility of a lung ultrasound score (LUS) has been described in the early phases of neonatal respiratory distress syndrome (RDS). We investigated lung ultrasound as a tool to monitor respiratory status in preterm neonates throughout the course of RDS. METHODS: Preterm neonates, stratified in 3 gestational age cohorts (25-27, 28-30, and 31-33 weeks), underwent lung ultrasound at weekly intervals from birth. Clinical data, respiratory support variables, and major complications (sepsis, patent ductus arteriosus, pneumothorax, and persistent pulmonary hypertension of the neonate) were also recorded. RESULTS: We enrolled 240 infants in total. The 3 gestational age intervals had significantly different LUS patterns. There was a significant correlation between LUS and the ratio of oxygen saturation to inspired oxygen throughout the admission, increasing with gestational age (b = -0.002 [P < .001] at 25-27 weeks; b = -0.006 [P < .001] at 28-30 weeks; b = -0.012 [P < .001] at 31-33 weeks). Infants with complications had a higher LUS already at birth (12 interquartile range 13-8 vs 8 interquartile range 12-4 control group; P = .001). In infants 25 to 30 weeks' gestation, the LUS at 7 days of life predicted bronchopulmonary dysplasia with an area under the curve of 0.82 (95% confidence interval 0.71 to 93). CONCLUSIONS: In preterm neonates affected by RDS, the LUS trajectory is gestational age dependent, significantly correlates with the oxygenation status, and predicts bronchopulmonary dysplasia. In this population, LUS is a useful, bedside, noninvasive tool to monitor the respiratory status.

IgM and IgA enriched polyclonal immunoglobulins reduce short term mortality in extremely low birth weight infants with sepsis: a retrospective cohort study.

BACKGROUND: Immunoglobulin supplementation is a debated strategy in fighting sepsis. We evaluated a polyclonal IgM and IgA enriched immunoglobulin (IgMeIVIG) preparation in reducing the short-term mortality in extremely low birth weight neonates (ELBW) with proven infection. METHODS: ELBW infants born from January 2008 to December 2014 were eligible for this retrospective case-control analysis if they were symptomatic and had a positive blood culture after 72 hours of life. Patients received antibiotic treatment with or without IgMeIVIG (intravenously, 250 mg/kg/day for 3 days) within the 24 hours from clinical suspicion as per indication of the attending physician. Short-term (7 and 21 days) mortality was the study primary outcome while secondary outcomes were: mortality at discharge, intraventricular hemorrhage, necrotizing enterocolitis, bronchopulmonary dysplasia, periventricular leukomalacia, and retinopathy of prematurity. RESULTS: Each group was composed by thirty-nine infants. Both groups were similar for antenatal steroids, mode of delivery, birth weight, gestational age and SNAPII score as indicator of disease severity. Infants receiving IgMeIVIG had a significantly lower short-term mortality compared with neonates receiving antibiotics alone: 6/39 (15%) vs. 14/39 (36%); P=0.038. No differences in other outcomes were found. CONCLUSIONS: This study shows that IgMeIVIG may have a role as adjuvant therapy in ELBW infants with proven sepsis. We warrant future prospective, blinded RCT studies where IgMeIVIG can be consistently used if needed throughout the NICU admission in ELBW septic neonates to appropriately evaluate its effect on mortality at discharge.

Oxidative Stress and Bronchopulmonary Dysplasia: Evidences From Microbiomics, Metabolomics, and Proteomics.

Bronchopulmonary dysplasia is a major issue affecting morbidity and mortality of surviving premature babies. Preterm newborns are particularly susceptible to oxidative stress and infants with bronchopulmonary dysplasia have a typical oxidation pattern in the early stages of this disease, suggesting the important role of oxidative stress in its pathogenesis. Bronchopulmonary dysplasia is a complex disease where knowledge advances as new investigative tools become available. The explosion of the "omics" disciplines has recently affected BPD research. This review focuses on the new evidence coming from microbiomics, metabolomics and proteomics in relation to oxidative stress and pathogenesis of bronchopulmonary dysplasia. Since the pathogenesis is not yet completely understood, information gained in this regard would be important for planning an efficacious prevention and treatment strategy for the future.

Lung ultrasound-guided emergency pneumothorax needle aspiration in a very preterm infant.

Pneumothorax is a frequent critical situation in the neonatal intensive care unit. Diagnosis relies on clinical judgement, transillumination and chest radiogram. We report the case of a very preterm infant suddenly developing significant and persistent desaturation and bradycardia. Re-intubation and cardiopulmonary resuscitation were performed. Clinical and cold light examination were not suggestive of pneumothorax according to two experienced neonatologists. A lung ultrasound scan showed evidence of right pneumothorax that was promptly aspirated. Approximately 20 min later, a chest radiogram confirmed the ultrasound diagnosis. Point-of-care lung ultrasound is a useful tool for detecting symptomatic pneumothorax and accelerating its treatment.

Are IgM-enriched immunoglobulins an effective adjuvant in septic VLBW infants?

AIM: To investigate the effectiveness of IgM-enriched immunoglobulins (IgM-eIVIG) in reducing short-term mortality of neonates with proven late-onset sepsis. METHODS: All VLBW infants from January 2008 to December 2012 with positive blood culture beyond 72 hours of life were enrolled in a retrospective cohort study. Newborns born after June 2010 were treated with IgM-eIVIG, 250 mg/kg/day iv for three days in addition to standard antibiotic regimen and compared to an historical cohort born before June 2010, receiving antimicrobial regimen alone. Short-term mortality (i.e. death within 7 and 21 days from treatment) was the primary outcome. Secondary outcomes were: total mortality, intraventricular hemorrhage, necrotizing enterocolitis, periventricular leukomalacia, bronchopulmonary dysplasia at discharge. RESULTS: 79 neonates (40 cases) were enrolled. No difference in birth weight, gestational age or SNAP II score (disease severity score) were found. Significantly reduced short-term mortality was found in treated infants (22% vs 46%; p = 0.005) considering all microbial aetiologies and the subgroup affected by Candida spp. Secondary outcomes were not different between groups. CONCLUSION: This hypothesis-generator study shows that IgM-eIVIG is an effective adjuvant therapy in VLBW infants with proven sepsis. Randomized controlled trials are warranted to confirm this pilot observation.

New perspectives in Respiratory Syncitial Virus infection.

Respiratory syncitial virus (RSV) is the most common cause of lower respiratory tract infections (LRTI) in children worldwide and it is associated with significant childhood morbidity. Acute infection may result in respiratory failure with varying degrees of severity, and increasing evidence supports a role of RSV infection as a key determinant for the development of subsequent chronic respiratory disease. Independent predictors of RSV severity include; prematurity, congenital heart disease, cystic fibrosis, immune defects and neuromuscular disorders. Passive immunization with palivizumab has proven to be safe and effective for preventing RSV hospitalization in infants at higher risk of acquiring severe RSV infection, but its expense and cumbersome monthly intravenous delivery schedule make it inaccessible to many. Furthermore, implementing prophylaxis in 32- to 35-week-gestational age infants and the mode of its administration still represent areas of uncertainty. In this review, we describe several aspects of RSV infection and analyze recent advances in the assessment of cost-effective palivizumab prophylaxis.

Bile acids modulate tight junction structure and barrier function of Caco-2 monolayers via EGFR activation.

Intestinal and systemic illnesses have been linked to increased gut permeability. Bile acids, whose luminal profile can be altered in human disease, modulate intestinal paracellular permeability. We investigated the mechanism by which selected bile acids increase gut permeability using a validated in vitro model. Human intestinal Caco-2 cells were grown in monolayers and challenged with a panel of bile acids. Transepithelial electrical resistance and luminal-to-basolateral fluxes of 10-kDa Cascade blue-conjugated dextran were used to monitor paracellular permeability. Immunoprecipitation and immunoblot analyses were employed to investigate the intracellular pathway. Redistribution of tight junction proteins was studied by confocal laser microscopy. Micromolar concentrations of cholic acid, deoxycholic acid (DCA), and chenodeoxycholic acid (CDCA) but not ursodeoxycholic acid decreased transepithelial electrical resistance and increased dextran flux in a reversible fashion. Coincubation of 50 muM CDCA or DCA with EGF, anti-EGF monoclonal antibody, or specific src inhibitor 4-Amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP-2) abolished the effect. A concentration of 50 muM of either CDCA or DCA also induced EGF receptor phosphorylation, occludin dephosphorylation, and occludin redistribution at the tight junction level in the same time frame and in a reversible fashion. We conclude that selected bile acids modulate intestinal permeability via EGF receptor autophosphorylation, occludin dephosphorylation, and rearrangement at the tight junction level. The effect is mediated by the src family kinases and is abolished by EGF treatment. These data also support the role of bile acids in the genesis of necrotizing enterocolitis and the protective effect of EGF treatment.

High tidal volume ventilation activates Smad2 and upregulates expression of connective tissue growth factor in newborn rat lung.

High tidal volume (V(T)) ventilation plays a key role in ventilator induced lung injury and bronchopulmonary dysplasia. However, little is known about the effect of high V(T) on expression of growth factors that are critical to lung development. In a previous study, we demonstrated that connective tissue growth factor (CTGF) inhibits branching morphogenesis. In this study, we investigated the effect of high V(T) on CTGF expression in newborn rat lungs. Newborn rats were ventilated with normal V(T) (10 mL/kg) or high V(T) (25 mL/kg) for 6 h. Nonventilated animals served as controls. We found that high V(T) upregulated CTGF expression. To identify the potential signaling pathways mediating high V(T) induction of CTGF, newborn rats were ventilated with high V(T) for 1 or 3 h. Temporal expression of TGF-betas, p-Smad2, Smad7, and CTGF was analyzed. High V(T) ventilation did not change gene expression of TGF-betas and Smad7 but induced rapid and sustained expression of p-Smad2 that precedes increased CTGF expression. CTGF and p-Smad2 were localized in bronchiolar epithelial cells, alveolar walls and septa. These data suggest that high V(t) ventilation activates the Smad2 pathway, which may be responsible for downstream induction of CTGF expression in newborn rat lungs.

Neonatal urinary cotinine correlates with behavioral alterations in newborns prenatally exposed to tobacco smoke.

Altered behavior due to prenatal smoke exposure was examined in 25 neonates born from smoking mothers who consumed at least 5 cigarettes/d during the entire gestation. Data were compared with 25 matched neonates born from nonsmoking mothers. Neonatal behavior was evaluated using the Brazelton Neonatal Behavioral Assessment Scale (BNBAS). Antenatal exposure to tobacco smoke at the end of the pregnancy was determined by measurement of urinary cotinine. Newborns from smoking mothers showed significant lower scores in various BNBAS items compared with neonates from nonsmoking mothers. A strong correlation was observed between infant irritability and urinary cotinine in newborns from smoker and nonsmoking mothers and with number of daily smoked cigarettes and maternal nicotine daily intake of infants exposed to active maternal smoking. Linear regression analysis showed that urinary cotinine was the best predictor of infant irritability (r(2) = 0.727). The latter was also associated to the neonate's low level of attention and poor response to inanimate auditory stimuli. Among infants from nonsmoking mothers, paternal smoking significantly correlated with infant urinary cotinine and infant irritability, being also the best predictor of irritability (r(2) = 0.364). Neonatal behavior can be significantly altered in a dose-dependent manner even after modest prenatal exposure to tobacco smoke.