[A single-center study on the incidence and mortality of preterm infants from 2006 to 2016]

Systematic Quantitative Analysis of Fetal Dexamethasone Exposure and Fetal Lung Maturation in Pregnant Animals: Model Informed Dexamethasone Precision Dose Study

Dexamethasone (DEX) was applied in neonatal respiratory distress syndrome treatment of pregnant women. We established a pharmacokinetics (PK)/pharmacodynamics(PD)/end point model of pregnant animals based on published data and then extrapolated to simulate fetal exposure and lung maturation in pregnant women. We first established the PK/PD/end point model for DEX in pregnant sheep. We considered the competitive effect of cortisol (Cort) and DEX binding with glucocorticoid receptor and then used the indirect response model to describe disaturated-phosphatidylcholine (DSPC) dynamics. Based on that, we established a regression relationship between DSPC and fetal lung volume (V40). We then extrapolated the PD/end point model of pregnant sheep to pregnant monkeys by corrected stages of morphologic lung maturation in two species. Finally, we utilized the interspecies extrapolation strategy to simulate fetal exposure (AUC0-48h) and V40 relationship in pregnant women. The current model could well describe the maternal-fetal PK of DEX in pregnant animals. Simulated DEX AUC0-24h values of the umbilical venous to maternal plasma ratio in pregnant sheep and monkeys were 0.31 and 0.27, respectively. The simulated Cort curve and V40 in pregnant sheep closely matched the observed data within a 2-fold range. For pregnant monkeys, model-simulated V40 were well fitted with external verification data, which showed good interspecies extrapolation performance. Finally, we simulated fetal exposure-response relationship in pregnant women, which indicated that the fetal AUC0-48h of DEX should not be less than 300 and 100 ng/mL·hr at GW28 and GW34 to ensure fetal lung maturity. The current model preliminarily provided support for clinical DEX dose optimization.

The Outcome- or Cost-Effectiveness Analysis of LUS-Based Care or CXR-Based Care of Neonatal Lung Diseases: The Clinical Practice Evidence from a Level Ⅲ NICU in China

OBJECTIVE

To compare the effect of managing neonatal lung disease with lung ultrasound (LUS) or chest X-ray (CXR) monitoring on health outcomes and cost-effectiveness.

METHODS

The data obtained from the NICU of the Beijing Chaoyang District Maternal and Child Healthcare Hospital were used as the study group, as LUS has completely replaced CXR in managing newborn lung disease in the hospital for the past 5 years. The primary outcomes of this study were the misdiagnosis rate of respiratory distress syndrome (RDS), the using status of mechanical ventilation, the incidence rate of bronchopulmonary dysplasia (BPD) and the survival rate in hospitalized infants. The secondary outcomes included the use pulmonary surfactant (PS), and the mortality rate of severe diseases (such as pneumothorax, pulmonary hemorrhage and RDS, etc.).

RESULTS

Managing neonatal lung disease with LUS monitoring may enable the following effects: The frequency of ventilator use reducing by 40.2%; the duration of mechanical ventilation reducing by 67.5%; and the frequency of ventilator weaning failure being totally avoided. A misdiagnosis rate of 30% for RDS was also avoided. The dosage of PS was significantly reduced by 50% to 75%. No BPD occurred in the LUS-based care group for 5 years. The fatality rates of RDS, pneumothorax and pulmonary hemorrhage decreased by 100%. The poor prognosis rate of VLBW infants decreased by 85%, and the total mortality rate of hospitalized infants decreased by 90%. Therefore, the cost of LUS-based care was inevitably saved.

CONCLUSIONS

Diagnosing and managing neonatal lung diseases with LUS monitoring have significant benefits, and this technology should be widely promoted and applied around the world.

An Innovative Model of Bronchopulmonary Dysplasia in Premature Infants

Bronchopulmonary dysplasia (BPD) is one of the common chronic lung diseases (CLD) of premature infants, which causes unpredictable consequences to the family and society. Therefore, the pathogenesis and prevention methods of BPD are the focus of current research, and the establishment of an effective and appropriate animal model of BPD in premature infants is the key to the research. In this study, premature rats were exposed to hyperoxia environment. Compared with the air group, the body weight and alveolar radiation count of the hyperoxia group decreased significantly, but there was no significant difference in body length. HE staining was used to observe the pathological changes of BPD in the lung tissue. The above results proved that under the hyperoxia condition, the BPD animal model of premature infants was successfully established, which provided a new choice for the future research of BPD.

[Research advances in the effect of environmental stress in the neonatal intensive care unit on the neurodevelopment of preterm infants and its epigenetics]

Adverse environmental stimulation in the neonatal intensive care unit (NICU) can affect neurodevelopment through epigenetic modification and thus has adverse effects on the long-term developmental outcome of preterm infants. Developmental care can reverse epigenetic changes in genes and promote neurodevelopment in preterm infants. This article reviews the influence of environmental stress in the NICU and developmental care on neurodevelopment in preterm infants, as well as related epigenetic effects, in order to provide a reference for epigenetic studies of preterm infants.