Aim: To analyze different methods to assess postnatal growth in a cohort of very premature infants (VPI) in a clinical setting and identify potential early markers of growth failure. Methods: Study of growth determinants in VPI (≤32 weeks) during hospital stay. Nutritional intakes and clinical evolution were recorded. Growth velocity (GV: g/kg/day), extrauterine growth restriction (%) (EUGR: weight < 10th centile, z-score < −1.28) and postnatal growth failure (PGF: fall in z-score > 1.34) at 36 weeks postmenstrual age (PMA) were calculated. Associations between growth and clinical or nutritional variables were explored (linear and logistic regression). Results: Sample: 197 VPI. GV in IUGR patients was higher than in non-IUGRs (28 days of life and discharge). At 36 weeks PMA 66.0% of VPIs, including all but one of the IUGR patients, were EUGR. Prevalence of PGF at the same time was 67.4% (IUGR patients: 48.1%; non-IUGRs: 70.5% (p = 0.022)). Variables related to PGF at 36 weeks PMA were initial weight loss (%), need for oxygen and lower parenteral lipids in the first week. Conclusions: The analysis of z-scores was better suited to identify postnatal growth faltering. PGF could be reduced by minimising initial weight loss and assuring adequate nutrition in patients at risk.

Very preterm infants (VPI, born at or before 32 weeks of gestation) are at risk of adverse health outcomes, from which they might be partially protected with appropriate postnatal nutrition and growth. Metabolic processes or biochemical markers associated to extrauterine growth restriction (EUGR) have not been identified. We applied untargeted metabolomics to plasma samples of VPI with adequate weight for gestational age at birth and with different growth trajectories (29 well-grown, 22 EUGR) at the time of hospital discharge. A multivariate analysis showed significantly higher levels of amino-acids in well-grown patients. Other metabolites were also identified as statistically significant in the comparison between groups. Relevant differences (with corrections for multiple comparison) were found in levels of glycerophospholipids, sphingolipids and other lipids. Levels of many of the biochemical species decreased progressively as the level of growth restriction increased in severity. In conclusion, an untargeted metabolomic approach uncovered previously unknown differences in the levels of a range of plasma metabolites between well grown and EUGR infants at the time of discharge. Our findings open speculation about pathways involved in growth failure in preterm infants and the long-term relevance of this metabolic differences, as well as helping in the definition of potential biomarkers.

We would like to thank Gounaris et al

Background/Objectives: Pneumothorax can be a major complication of neonatal lung diseases. We aim to delineate trends and describe the main outcomes related to pneumothorax in very preterm infants (VPI). Methods: Preterm infants < 32 weeks of gestation admitted in two-level III neonatal intensive care units (1995–2019) were included. Risk factors and outcomes were assessed by logistic regression and adjusted for gestational age (GA). Results: In total, 4271 VPI with a mean GA of 28.7 ± 2.3 weeks were evaluated. Pneumothorax was diagnosed in 174 patients (4.1%, 95% Confidence Interval (CI) 3.5–4.7) with its incidence inversely proportional to GA: 9.9% in 23–25 w and 2.1% in 30–31 w (p < 0.001), but stable over the years 1995–1999 (5.2%) and 2015–2019 (4.2%) (p = 0.309). Patients with pneumothorax exhibited higher rates of severe intraventricular hemorrhage (IVH) (Odds Ratio (OR) = 2.0 (95%CI 1.3–3.1), p = 0.003), bronchopulmonary dysplasia (OR = 2.7 (95%CI 1.7–4.4), p < 0.001), and death (OR = 8.5 (95%CI 6.2–11.6), p < 0.001). Independent risk factors for pneumothorax were GA, prolonged premature rupture of membranes, and intubation in the delivery room. The composite outcome of death or severe IVH was higher in patients with pneumothorax with an adjusted OR = 6.7 (95%CI 4.7–9.6), p < 0.001. Although VPI mortality has significantly decreased over the years (20.3% 1995–1999 and 11.7% 2015–2019, p < 0.001), we found no significant difference in pneumothorax-related deaths. Conclusion: Pneumothorax remains a serious threat to VPI, leading to a higher incidence of morbidity, and mortality attributable to this complication has not decreased. Preventive strategies and early recognition are essential for improving disability-free survival in VPI.