Lung Microbiota and Ventilator-Associated Pneumonia in the Neonatal Period.

The lung microbiota is a complex community of microorganisms that colonize the respiratory tract of individuals from, or even before, birth. Although the lungs were traditionally believed to be sterile, recent research has shown that there is a diversity of bacterial species in the respiratory system. Knowledge about the lung microbiota in newborns and its relationship with bacterial infections is of vital importance to understand the pathogenesis of respiratory diseases in neonatal patients undergoing mechanical ventilation. In this article, the current evidence on the composition of the lung microbiota in newborns will be reviewed, as well as the risks that an altered microbiota can impose on premature newborns. Although advances in neonatal intensive care units have significantly improved the survival rate of preterm infants, the diagnosis and treatment of ventilator-associated pneumonia has not progressed in recent decades. Avoiding dysbiosis caused by inappropriate use of antibiotics around birth, as well as avoiding intubation of patients or promoting early removal of endotracheal tubes, are among the most important preventive measures for ventilator-associated pneumonia. The potential benefit of probiotics and prebiotics in preventing infectious, allergic or metabolic complications in the short or long term is not clearly established and constitutes a very important field of research in perinatal medicine.

Comparative analysis of foetal and neonatal growth curves.

INTRODUCTION: Our aim was to determine which foetal or neonatal growth curves discriminate the probability of dying of newborns with low birth weight for their gestational age (small for gestational age, SGA) and sex (weight < 10th percentile) and to establish the curves that are presumably most useful for monitoring growth through age 10 years. MATERIAL AND METHODS: The analysis included every neonate (15 122) managed in our hospital (2013-2022) and all neonates born preterm before 32 weeks (6913) registered in the SEN1500 database (2019-2022). We considered most useful those curves with the highest likelihood ratio (LR) for dying with or without a history of SGA in each subgroup of gestational ages. Theoretically, the optimal curves for monitoring growth would be those with a higher R2 in the quantile regression formulas for the 50th percentile. RESULTS: The growth curves exhibiting the strongest association between SGA and hospital mortality are the Intergrowth fetal curves and the Fenton neonatal curves in infants born preterm before 32 weeks. However, the optimal curves for premature babies and neonates overall were those of Olsen and Intergrowth. The most useful curves to monitor anthropometric values alone until age 10 years of age are the longitudinal Intergrowth curves followed by the WHO standards, but if a single reference is desired from birth through age 10 years, the best option is the Fenton curves followed by the WHO standards. CONCLUSIONS: The Intergrowth reference provides the most discriminating foetal growth curves. In neonatal clinical practice, the optimal references are the Fenton followed by the WHO charts.

Variations in the number of births by day of the week, and morbidity and mortality in very-low-birth-weight infants / Variações no número de partos por dia da semana e morbidez e mortalidade em neonatos com muito baixo peso ao nascer

Abstract Objective: To know the distribution of births of very low birth weight infants by day of the week, and whether this distribution affects the morbidity and mortality in this group of patients. Methods: This was a retrospective analysis of data collected prospectively in the Spanish SEN1500 network (2002-2011). Outborn infants, patients with major congenital anomalies, and those who died in the delivery room were excluded. Births were grouped into "weekdays" and "weekends." A multivariate logistic regression analysis was conducted to evaluate the independent effect of the birth moment on outcomes, and Cox regression for survival. Results: Out of a total of 27,205 very low birth weight infants born at and/or admitted to the participating centers, 22,961 (84.4%) met inclusion criteria. A reduction of 24% in the number of births was observed during the "weekends" compared with "weekdays". In the raw analysis, patients born on weekends exhibited higher morbidity and mortality (mortality rate: 14.2% vs. 16.5%, p < 0.001), but differences were no longer significant after adjusting for confounding factors. Conclusions: The present results suggest that current care practices reduce the proportion of births during the weekends and tend to cluster some high-risk births during this period, increasing crude morbidity and mortality. However, after adjusting for confounding factors, the differences disappear, suggesting that overall care coverage in these centers is appropriate.

Resumo Objetivo: Conhecer a distribuição dos partos de neonatos com muito baixo peso ao nascer durante a semana e se essa distribuição afeta a morbidez e a mortalidade nesse grupo de pacientes. Método: Esta é uma análise retrospectiva de dados coletados prospectivamente na rede espanhola SEN1500 (2002-2011). Foram excluídos neonatos nascidos em outro local, pacientes com grandes anomalias congênitas e pacientes falecidos na sala de parto. Os partos foram agrupados em "Dias úteis" e "Final de semana". Foi realizada uma análise de regressão logística multivariada para avaliar o efeito independente do parto sobre os resultados e uma regressão de Cox para avaliar a sobrevida. Resultados: Do total de 27.205 neonatos com muito baixo peso ao nascer nascidos e/ou internados nos centros participantes, 22.961 (84,4%) atenderam aos critérios de inclusão. Houve uma redução de 24% no número de partos no "Final de semana" em comparação com os "Dias úteis". Na análise bruta, os pacientes nascidos em finais de semana apresentaram maior morbidez e mortalidade (Taxa de mortalidade: 14,2% em comparação a 16,5%, p < 0,001), porém as diferenças não eram mais significativas após o ajuste aos fatores de confusão. Conclusões: Nossos resultados sugerem que as práticas atuais de atendimento reduzem a proporção de partos em finais de semana e tendem a agrupar alguns partos de alto risco nesse período, aumentando a morbidez e mortalidade brutas. Contudo, após o ajuste aos fatores de risco, as diferenças desaparecem, sugerindo que a cobertura de atendimento geral em nossos centros é adequada.