Higher awakening threshold of preterm infants in prone position may be a risk factor for SIDS.

AIM: The supine sleeping position in the prevention of sudden infant death syndrome in preterm infants is poorly understood. We aimed to investigate the effect of sleep posture on cardiorespiratory parameters and movement patterns in preterm infants close to discharge. METHODS: This observational study included neonates born in 2022 at the University Hospital Schleswig-Holstein, Lübeck, Germany. Motion sensor data, heart rate, respiratory rate and oxygen saturation were recorded for infants with postconceptional age 35-37 weeks during sleep in the prone and supine positions. RESULTS: We recorded data from 50 infants, born at 31 (24-35) weeks of gestation (mean(range)), aged 5.2 ± 3.7 weeks (mean ± SD), of whom 48% were female. Five typical movement patterns were identified. In the prone position, the percentage of calm, regular breathing was higher and active movement was less frequent when compared to the supine position. The percentage of calm irregular breathing, number of apnoeas, bradycardias, desaturations and vital sign changes were not influenced by position. CONCLUSION: The prone position seems to be associated with a higher arousal threshold. The supine position appears advantageous for escape from life-threatening situations such as sudden infant death syndrome.

The Derivation of Epigastric Motion to Assess Neonatal Breathing and Sleep: An Exploratory Study.

INTRODUCTION: New non-medical monitors are offered for respiration monitoring of neonates. Epigastric motion during sleep was investigated by means of a wearable tracker in parallel to clinical monitoring. COHORT: 23 hospitalised neonates ready for discharge. METHODS: A 3-axes-accelerometer and -gyroscope was placed in a standard epigastric position. Between two routine care rounds signals were recorded in parallel to monitoring of impedance pneumography (IP), ECG and pulse oximetry. Motion signals vs. time charts were evaluated using 10-min episodes and semiquantitatively assigned to breathing signal quality, regular breathing, periodic breathing and confounding artefacts. The results were compared with the impedance pneumographic data. RESULTS: 26 recordings (mean duration: 210 min/infant) were conducted without bradycardia or apnea alarm. The gestational age at birth ranged 28.9 to 41.1 and at recording from 35.6 to 42.3 postmenstrual weeks. Motion patterns of quiet sleep with regular breathing, periodic breathing and active sleep with confounding body movements were found. The longitudinal and transversal gyroscope axes resulted in best signal quality. Periodic breathing was found in up to 80% of episodes and decreased inversely with gestational age showing significantly more periodic breathing in preterm infants. Respiration signals of the gyroscope vs. IP showed a low bias and highly variating frequencies. CONCLUSIONS: Standardized motion trackers may detect typical neonatal breathing and body-motion-patterns, that could help to classify neonatal sleep. Respiratory rates can only be determined during quiet sleep.

A randomised controlled trial in preterm infants comparing prophylactic with selective "less invasive surfactant administration" (pro.LISA).

BACKGROUND: Respiratory distress syndrome is the main cause of mortality and morbidity in preterm infants. "Less invasive surfactant administration" (LISA), which describes intratracheal surfactant administration to spontaneously breathing infants via a small diameter tube, is recommended as the first-line treatment in preterm infants with more than 30% supplemental oxygen. Prophylactic use of LISA in preterm infants with less than 30% supplemental oxygen was not tested in randomised controlled trials yet, and long-term outcome data of the procedure are scarce. METHODS: Preterm infants with a gestational age between 25 weeks + 0 days and 28 weeks + 6 days who are breathing spontaneously on continuous positive airway pressure with supplemental oxygen at or below 30% in the first hour of life will be randomised to a prophylactic LISA treatment with 100-200 mg surfactant intratracheally per kilogramme bodyweight (intervention group) or will continue the continuous positive airway pressure treatment (control group). Participants will have follow-up until age 5 years. At that time, the children will be tested by spirometry, and forced expiratory volume within 1-s z-scores will be compared between the intervention and control groups as the primary outcome parameter of the trial. Secondary endpoints include additional lung function parameters, endurance, motor development, intelligence, and sensitivity for infectious lung diseases. Short-term safety assessment will be done after completed enrolment (n = 698) and discharge of all infants. This safety assessment will include in-hospital mortality and short-term complications. DISCUSSION: Robust data concerning the possible long-term benefits of prophylactic LISA treatment are lacking. The current observational data from the German Neonatal Network indicate that approximately 50% of preterm infants with supplemental oxygen at or below 30% within the first hour of life are treated with LISA. The pro.LISA trial will provide short- and long-term outcomes of preterm infants receiving prophylactic treatment and will clarify if prophylactic treatment should be given to all preterm infants or if the current practice of selective treatment if supplemental oxygen exceeds 30% is more appropriate. TRIAL REGISTRATION: German Clinical Trials Register DRKS00028086. Prospectively registered on 8 February 2022.

Lung Function of Preterm Children Parsed by a Polygenic Risk Score for Adult COPD.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) in adults is a result of environmental risk factors and genetic factors. Polygenic COPD risk scores are highly predictive for lung function in adults. We hypothesized that a polygenic COPD risk score is also predictive for lung function in children who are born preterm. METHODS: Infants with a birth weight of less than 1500 g (n=17,394) were enrolled in the German Neonatal Network. Among these children, we included those with chip genotyping and 5-year follow-up assessment (n=1957) in this analysis. A polygenic COPD risk score derived in adults with COPD was calculated on the basis of 1,637,882 single-nucleotide polymorphisms associated with forced expiratory volume within 1 second (FEV1) and 1,179,331 single-nucleotide polymorphisms associated with FEV1/FVC (forced vital capacity). This score was related to FEV1, FVC, and FEV1/FVC z scores by linear regression analysis. RESULTS: At a mean age at follow-up of 5.8±0.4 years, the polygenic COPD risk score was strongly associated with FEV1 (−0.05 z score/decile, P=6.5 × 10−9) and FEV1/FVC (−0.07 z score/decile, P=4.4 × 10−11) but not FVC. Children in the 10th decile of the polygenic COPD risk score ­ that is, those at the highest risk ­ had a mean FEV1 z score of −1.74 (±1.1), indicating lower lung function by these measures and higher rates of obstructive bronchitis. CONCLUSIONS: The upper deciles of a polygenic COPD risk score derived in adults identified a subgroup of children who were born preterm and who are at high risk for obstructive pulmonary disease of prematurity. This finding supports the notion that COPD-associated genes strongly impact lung function in premature children. (Funded by the German Federal Ministry of Education and Research.)

Lactoferrin and Human Neutrophil Protein (HNP) 1-3 Levels During the Neonatal Period in Preterm Infants.

Antimicrobial polypeptides (APPs) are part of the innate immune system, but their specific role in the context of preterm birth is not yet understood. The aim of this investigation was to determine the systemic expression of APPs, i.e., lactoferrin (LF) and human neutrophil protein (HNP) 1-3 in preterm infants in the period of highest vulnerability for infection and to correlate these biomarkers with short-term outcome. We therefore conducted a prospective two-center study including plasma samples of 278 preterm infants and 78 corresponding mothers. APP levels were analyzed on day 1, 3, 7, and 21 of life via enzyme-linked immunosorbent assay (ELISA). The levels of LF and HNP1-3 remained stable during the first 21 days of life and were not influenced by maternal levels. Elevated APP levels were found at day 1 in infants born to mothers with amniotic infection syndrome (AIS vs. no AIS, mean ± SD in ng/ml: LF 199.8 ± 300 vs. 124.1 ± 216.8, HNP 1-3 16,819 ± 36,124 vs. 8,701 ± 11,840; p = 0.021, n = 179). We found no elevated levels of APPs before the onset of sepsis episodes or in association with other short-term outcomes that are in part mediated by inflammation such as necrotizing enterocolitis (NEC) or retinopathy of prematurity (ROP). Interestingly, infants developing bronchopulmonary dysplasia (BPD) showed higher levels of HNP1-3 on day 21 than infants without BPD (13,473 ± 16,135 vs. 8,388 ± 15,938, n = 111, p = 0.008). In infants born without amniotic infection, levels of the measured APPs correlated with gestational age and birth weight. In our longitudinal study, systemic levels of LF and HNP 1-3 were not associated with postnatal infection and adverse short-term outcomes in preterm infants.

Progressive Respiratory Insufficiency in a Teenager with Diaphragmatic Hypomotility Due to a Novel Combination of Gliomedin Gene Variants.

Lethal congenital contracture syndrome 11 (LCCS11) is a form of arthrogryposis multiplex congenita (AMC) which is associated with mutations in the gliomedin gene (GLDN) and has been known to be severely life-shortening, mainly due to respiratory insufficiency. Patients with this condition have been predominantly treated by pediatricians as they usually do not survive beyond childhood. In this case report, we present a young adult who developed severe progressive respiratory insufficiency as a teenager due to diaphragmatic hypomotility and was diagnosed with LCCS11 following the discovery of compound heterozygous pathogenic variants in GLDN. This case demonstrates the importance of screening for neuromuscular diseases in well-child visits and follow-ups of patients at risk for gross and fine motor function developmental delay. It also underscores the significance of including LCCS11 and other axonopathies in the differential diagnosis of juvenile onset of respiratory insufficiency, highlights that patients with this condition may present to adult practitioners and questions whether the nomenclature of this condition with various phenotypes should be reconsidered due to the stigmatizing term 'lethal'.

Characterization of phospholipid-modified lung surfactant in vitro and in a neonatal ARDS model reveals anti-inflammatory potential and surfactant lipidome signatures.

A strong inflammatory immune response drives the lung pathology in neonatal acute respiratory distress syndrome (nARDS). Anti-inflammatory therapy is therefore a promising strategy for improved treatment of nARDS. We demonstrate a new function of the anionic phospholipids POPG, DOPG, and PIP2 as inhibitors of IL-1ß release by LPS and ATP-induced inflammasome activation in human monocyte-derived and lung macrophages. Curosurf® surfactant was enriched with POPG, DOPG, PIP2 and the head-group derivative IP3, biophysically characterized and applicability was evaluated in a piglet model of nARDS. The composition of pulmonary surfactant from piglets was determined by shotgun lipidomics screens. After 72 h of nARDS, levels of POPG, DOPG, and PIP2 were enhanced in the respective treatment groups. Otherwise, we did not observe changes of individual lipid species in any of the groups. Surfactant proteins were not affected, with the exception of the IP3 treated group. Our data show that POPG, DOPG, and PIP2 are potent inhibitors of inflammasome activation; their enrichment in a surfactant preparation did not induce any negative effects on lipid profile and reduced biophysical function in vitro was mainly observed for PIP2. These results encourage to rethink the current strategies of improving surfactant preparations by inclusion of anionic lipids as potent anti-inflammatory immune regulators.

Lymphangioma of the fetal neck within the PIK3CA-related-overgrowth spectrum (PROS): A case report.

The delineation of the prenatal diagnostic key features of PIK3CA-related overgrowth spectrum disorders will assume a crucial part in future and a prenatal diagnosis of the causing mutations would provide physicians with a simplified interdisciplinary perinatal management.

Five Year Follow Up of Extremely Low Gestational Age Infants after Timely or Delayed Administration of Routine Vaccinations.

This study is aimed at detecting the rate of untimely immunization in a large cohort of extremely low gestational age neonates (ELGANs) of the German Neonatal Network (GNN) and at addressing risk factors for delayed vaccination and associated long-term consequences. We performed an observational study of the GNN between 1st January 2010 and 31st December 2019. The immunization status for the hexavalent and pneumococcal immunization was evaluated in n = 8401 preterm infants <29 weeks of gestation. Univariate analysis and logistic/linear regression models were used to identify risk factors for vaccination delay and outcomes at a 5-year follow-up. In our cohort n = 824 (9.8%) ELGANs did not receive a timely first immunization with the hexavalent and pneumococcal vaccine. Risk factors for delayed vaccination were SGA status (18.1% vs. 13.5%; OR 1.3; 95% CI: 1.1-1.7), impaired growth and surrogates for complicated clinical courses (i.e., need for inotropes, necrotizing enterocolitis). At 5 years of age, timely immunized children had a lower risk of bronchitis (episodes within last year: 27.3% vs. 37.7%; OR 0.60, 95% CI: 0.42-0.86) but spirometry measures were unaffected. In conclusion, a significant proportion of ELGANs are untimely immunized, specifically those with increased vulnerability, even though they might particularly benefit from the immune-promoting effects of a timely vaccination.

LAMP3 deficiency affects surfactant homeostasis in mice.

Lysosome-associated membrane glycoprotein 3 (LAMP3) is a type I transmembrane protein of the LAMP protein family with a cell-type-specific expression in alveolar type II cells in mice and hitherto unknown function. In type II pneumocytes, LAMP3 is localized in lamellar bodies, secretory organelles releasing pulmonary surfactant into the extracellular space to lower surface tension at the air/liquid interface. The physiological function of LAMP3, however, remains enigmatic. We generated Lamp3 knockout mice by CRISPR/Cas9. LAMP3 deficient mice are viable with an average life span and display regular lung function under basal conditions. The levels of a major hydrophobic protein component of pulmonary surfactant, SP-C, are strongly increased in the lung of Lamp3 knockout mice, and the lipid composition of the bronchoalveolar lavage shows mild but significant changes, resulting in alterations in surfactant functionality. In ovalbumin-induced experimental allergic asthma, the changes in lipid composition are aggravated, and LAMP3-deficient mice exert an increased airway resistance. Our data suggest a critical role of LAMP3 in the regulation of pulmonary surfactant homeostasis and normal lung function.

Active perinatal care of preterm infants in the German Neonatal Network.

OBJECTIVE: To determine if survival rates of preterm infants receiving active perinatal care improve over time. DESIGN: The German Neonatal Network is a cohort study of preterm infants with birth weight <1500 g. All eligible infants receiving active perinatal care are registered. We analysed data of patients discharged between 2011 and 2016. SETTING: 43 German level III neonatal intensive care units (NICUs). PATIENTS: 8222 preterm infants with a gestational age between 22/0 and 28/6 weeks who received active perinatal care. INTERVENTIONS: Participating NICUs were grouped according to their specific survival rate from 2011 to 2013 to high (percentile >P75), intermediate (P25-P75) and low (

The effect of less invasive surfactant administration on cerebral oxygenation in preterm infants.

AIM: To determine the regional cerebral tissue oxygenation saturation (rcSO2 ) in a group of infants requiring less invasive surfactant administration (LISA) as compared to infants with continuous positive airway pressure (CPAP) only. METHODS: In preterm infants with a gestational age 26 0/7-31 6/7 weeks, we conducted an observational study using near-infrared spectroscopy (NIRS) in the first 120 hours of life. RESULTS: We analysed the data of 22 infants who never received surfactant (CPAP), 22 infants had LISA and CPAP (LISA) and 6 infants received surfactant via endotracheal tube (ETT). Four infants had both surfactant application modes including six LISA applications. In total, there were 32 successful LISA applications but 44 attempts; 13/44 (30%) of LISA attempts resulted in a 20% decrease of rcSO2 . During the first 120 hours of life, rcSO2 values of CPAP were similar to those of infants in the LISA group, that is median rcSO2 values 90% vs 85%, respectively (P = .126). Episodes with rcSO2 values <65% were 0.4% in the CPAP group as compared to 4.8% in the LISA group (P < .001). CONCLUSION: Our observational data indicate that rcSO2 values of infants in the LISA group were similar to the CPAP group.

Natural Derived Surfactant Preparation As a Carrier of Polymyxin E for Treatment of Pseudomonas aeruginosa Pneumonia in a Near-Term Rabbit Model.

BACKGROUND: Pulmonary surfactant spreads rapidly over the airway epithelium, a property that could be harnessed to transport drugs into the lungs. For efficient drug delivery, an interaction between pulmonary surfactant and the drug to be administered is likely needed. On the other hand, the interaction should not compromise the activity of surfactant or the drug once delivered in vivo. The antibiotics gentamicin (an aminoglycoside) and polymyxin E represent drugs that could benefit from being delivered directly to the lung, thereby increasing local concentrations and reducing systemic side effects. Our aim was to study how the animal-derived surfactant poractant alfa (Curosurf®) affects the activities of polymyxin E and gentamicin against Pseudomonas aeruginosa. METHODS: In vitro antimicrobial assays and a neonatal near-term rabbit model were used to evaluate the combinations of antibiotics and surfactant against Pseudomonas aeruginosa. RESULTS: The bactericidal activity of polymyxin E, but not of gentamicin, against P. aeruginosa was partly reduced in vitro in the presence of poractant alfa. In contrast, in the rabbit model of P. aeruginosa pneumonia, polymyxin E administrated together with surfactant was superior in lowering the bacterial load in the lungs compared to polymyxin E alone, without affecting plethysmographically recorded lung compliance. CONCLUSIONS: The results suggest that polymyxin E interacts with poractant alfa, which reduces the antibacterial effect in vitro. However, when polymyxin E mixed with surfactant is used in the in vivo pneumonia model, increased bactericidal effect was observed. This may be due to a more efficient spreading mediated by interactions between polymyxin E and surfactant. These results warrant further studies of surfactant preparations for drug delivery against lung infections.

Health of VLBW infants in Germany at five years of age: What do parents describe?

BACKGROUND: There are only few data on medical problems and utilization of health services of former very low birth weight (VLBW) children at preschool age. STUDY DESIGN: At five years of age parents of a cohort of VLBW children (N=862) received questionnaires, a medical interview and examination. The results were compared to the KIGGS cohort (Deutscher-Kinder-und Jugendgesundheitssurvey, N=777). RESULTS: Parents of the VLBW and KIGGS cohort reported a very good or good health in 95% in their children. When compared to the KIGGS cohort, families in the VLBW cohort had a lower social economic status. The VLBW cohort suffered more frequently from disabilities (9.6% vs. 1.4%), from chronic bronchitis (45% vs. 17%) and from recurrent pain (headaches (20% vs. 7%), ear (16% vs. 6%), throat (23% vs. 8%), tooth (10% vs. 3%)). The VLBW cohort received more specialized care (ophthalmologist, ENT, orthopaedics, paediatric neurologist). CONCLUSION: Families of VLBW children report a good health status in their children, but they utilized more specialized care. Higher rates of pain are reported in the VLBW cohort. Chronic bronchitis and various upper respiratory infections cause an increased morbidity in former VLBW children. Follow up programs are needed to develop optimal treatment and prevention strategies for these problems.

Comparison of Polymyxin E and Polymyxin B as an Additive to Pulmonary Surfactant in Escherichia coli Pneumonia of Ventilated Neonatal Rabbits.

BACKGROUND: Ascending maternofetal bacterial infections often result in premature birth and neonatal respiratory distress. These neonates are treated with exogenous pulmonary surfactant (SF) and systemic antibiotics. Polymyxins are antimicrobiotic peptides that may bind to SF phospholipids. OBJECTIVES: Does topical administration of SF/polymyxin reduce bacterial growth in neonatal rabbit pneumonia and improve pulmonary function? METHODS: Neonatal rabbits were tracheotomized and treated intratracheally with mixtures of porcine SF, SF/polymyxin E (PxE), or polymyxin B (PxB). Control animals received saline. Animals were then inoculated with Escherichia coli and ventilated for 4 h. During the experiment, peak insufflation pressures, dynamic lung compliance, and ECG were recorded. Pulmonary and renal bacterial load were determined. Lung histology was performed. Lung and kidney IL-8 were measured in subgroups. RESULTS: Eighty-five animals were included in 2 experimental series, of which 78% survived 4 h of ventilation. E. coli inoculation caused severe neonatal pneumonia with median IL-8 levels of 2.2 ng/g in the lungs compared to a median of 0.2 ng/g in the lungs of the saline controls (p < 0.01). Lung compliance after 4 h was significantly increased at a mean of 0.48 ml/(kg·cm H2O) in the SF group and 0.43 in the SF + PxE group compared to 0.35 in the E. coli group (p < 0.01). In direct comparison, bacterial growth found in the E. coli group was reduced 20-fold in the SF + PxB group compared to 75-fold in the SF + PxE group. CONCLUSION: Addition of polymyxin to SF effectively promotes antimicrobial treatment and improves lung function in neonatal pneumonia of rabbits.

Surface tension of airway aspirates withdrawn during neonatal resuscitation reflects lung maturity.

The indications for treatment of neonates with exogenous pulmonary surfactant are still discussed controversially. Some premature neonates are sufficiently treated by CPAP, others need conventional ventilation and/or surfactant. The available lung maturity tests have limitations. The captive bubble surfactometer (CBS) provides measurement of surface activity from rather small amounts of surfactant. This study aimed to determine surface activity from small volume aspirates of the upper airways of neonates by means of the CBS and to correlate the results with clinical data. Small upper airway aspirates from 159 neonates (gestational age 25-42 weeks) were withdrawn and concentrated 16.7-fold by ultracentrifugation and resuspension in saline. Surface activities after 5 min of adsorption were determined in the CBS and correlated to the perinatal data (e.g., gestational age, birth weight, gender), airway interventions (like CPAP, conventional ventilation) and surfactant treatment. Additionally, 27 samples were analyzed for surfactant specific phosphatidylcholine concentrations by using electrospray ionization tandem mass-spectroscopy. Surface activities show a significant correlation to gestational age, birth weight, and the need for airway interventions. Comparing the need for airway interventions versus surface activity, a receiver operating characteristic calculated a sensitivity of 0.77 and a specificity of 0.72 at a "cut off" of 44 mN/m. Surface activity correlates significantly with the phosphatidylcholine concentrations and the latter one correlates with the gestational age. Determination of surface activity from upper airway aspirates is feasible. Further clinical studies are needed to prove the predictive value of the method.

Pulmonary surfactant preserves viability of alveolar type II cells exposed to polymyxin B in vitro.

BACKGROUND: Exogenous surfactant derived from animal lungs is applied for treatment of surfactant deficiency. By means of its rapid spreading properties, it could transport pharmaceutical agents to the terminal air spaces. The antimicrobial peptide Polymyxin B (PxB) is used as a topical antibiotic for inhalation therapy. Whereas it has been shown that PxB mixed with surfactant is not inhibiting surface activity while antimicrobiotic activity is preserved, little is known concerning the effects on synthesis of endogenous surfactant in alveolar type II cells (ATIIC). OBJECTIVE: To investigate ATIIC viability and surfactant-exocytosis depending on PxB and/or surfactant exposure. METHODS: ATIIC were isolated from rat lungs as previously described and were cultivated for 48 h. After incubation for a period of 1-5 h with either PxB (0.05 or 0.1 mg/ml), modified porcine surfactant (5 or 10 mg/ml) or mixtures of both, viability and exocytosis (spontanously and after stimulation) were determined by fluorescence staining of intracellular surfactant. RESULTS: PxB 0.1 mg/ml, but not porcine surfactant or porcine surfactant plus PxB reduces ATIIC-viability. Only PxB alone, but not in combination with porcine surfactant, rapidly reduces fluorescence in ATIIC at maximum within 3 h, indicating stimulation of exocytosis. Subsequent ionomycin-stimulation does not further increase exocytosis of PxB incubated ATIIC. In presence of surfactant, stimulating effects of PxB and ionomycin on exocytosis are reduced. CONCLUSION: PxB alone shows negative effects on ATIIC, which are counterbalanced in mixtures with surfactant. So far, our studies found no results discouraging the concept of a combined treatment with PxB and surfactant mixtures.