Risk factors for bronchopulmonary dysplasia in five Portuguese neonatal intensive care units

A Systematic Review: Is Early Fluid Restriction in Preterm Neonates Going to Prevent Bronchopulmonary Dysplasia?

Preterm birth causes constant challenges, with bronchopulmonary dysplasia (BPD) being a major concern. Immediately after birth, it takes time to establish feeding between the mother and the premature baby. During this time, the telological shifting of fluid from extracellular space to intracellular space will help the baby; this transition should be smooth. Both normal physiologic changes and pathophysiologic events are capable of disrupting this delicate fluid shifting that occurs in very low-birth-weight infants during the first week of life. The immaturity of the renal system and evaporative losses complicate this process. This lack of fluid displacement can be associated with an increased amount of water in the lungs and reduced lung compliance. This can lead to the need for more ventilatory support and a higher oxygen requirement, which, in turn, leads to lung damage. The fluid restriction is also associated with complications such as severe dehydration, intracranial hemorrhage, and bilirubin toxicity. However, the administration of large amounts of fluid and salt is associated with an increased incidence of patent ductus arteriosus, BPD, necrotizing enterocolitis, and intraventricular hemorrhage. There were studies conducted in both the pre-surfactant and surfactant eras that were inconclusive regarding fluid restriction in BPD. We only included very recent studies. This systematic review attempts to summarize the current evidence, focusing on the efficacy and safety of early fluid management in preterm infants. This reduces the risk of BPD and improves outcomes for premature infants. As we know, intact survival is very important. Our review supported the early fluid restriction.

Development and Validation of a Risk Scoring Tool for Bronchopulmonary Dysplasia in Preterm Infants Based on a Systematic Review and Meta-Analysis

Background: Bronchopulmonary dysplasia (BPD) is the most common serious pulmonary morbidity in preterm infants with high disability and mortality rates. Early identification and treatment of BPD is critical. Objective: This study aimed to develop and validate a risk scoring tool for early identification of preterm infants that are at high-risk for developing BPD. Methods: The derivation cohort was derived from a systematic review and meta-analysis of risk factors for BPD. The statistically significant risk factors with their corresponding odds ratios were utilized to construct a logistic regression risk prediction model. By scoring the weights of each risk factor, a risk scoring tool was established and the risk stratification was divided. External verification was carried out by a validation cohort from China. Results: Approximately 83,034 preterm infants with gestational age < 32 weeks and/or birth weight < 1500 g were screened in this meta-analysis, and the cumulative incidence of BPD was about 30.37%. The nine predictors of this model were Chorioamnionitis, Gestational age, Birth weight, Sex, Small for gestational age, 5 min Apgar score, Delivery room intubation, and Surfactant and Respiratory distress syndrome. Based on the weight of each risk factor, we translated it into a simple clinical scoring tool with a total score ranging from 0 to 64. External validation showed that the tool had good discrimination, the area under the curve was 0.907, and that the Hosmer-Lemeshow test showed a good fit (p = 0.3572). In addition, the results of the calibration curve and decision curve analysis suggested that the tool showed significant conformity and net benefit. When the optimal cut-off value was 25.5, the sensitivity and specificity were 0.897 and 0.873, respectively. The resulting risk scoring tool classified the population of preterm infants into low-risk, low-intermediate, high-intermediate, and high-risk groups. This BPD risk scoring tool is suitable for preterm infants with gestational age < 32 weeks and/or birth weight < 1500 g. Conclusions: An effective risk prediction scoring tool based on a systematic review and meta-analysis was developed and validated. This simple tool may play an important role in establishing a screening strategy for BPD in preterm infants and potentially guide early intervention.

The association of vitamin D and vitamin E levels at birth with bronchopulmonary dysplasia in preterm infants

BACKGROUND

Despite improvements made in neonatal care, bronchopulmonary dysplasia (BPD) is still the most common respiratory disease in preterm infants. The relationship between the blood contents of vitamin D/E in premature infants and BPD is still controversial.

METHODS

Preterm infants were recruited as the research subjects. On the basis of the inclusion and exclusion criteria, a total of 133 eligible cases were finally included. A total of 63 preterm infants with a clear diagnosis of BPD and 5 preterm infants who died before the diagnosis of BPD were in the case group, and 65 non-BPD preterm infants with equivalent baseline characteristics were in the control group. The BPD group included 38 cases in Grade Ⅰ, 18 cases in Grade Ⅱ, and 12 cases in Grade Ⅲ. The contents of vitamin D and E in the cord blood of different groups were detected by high-performance liquid chromatography and enzyme-linked immunosorbent assay. Correlation analysis adopted the Pearson correlation analytic method.

RESULTS

The serum vitamin D and E levels at birth were remarkably lower in the BPD group than the non-BPD group, both of which were also correlated with the severity of BPD. The vitamin D and E contents were negatively correlated with the oxygen support duration required for premature infants with BPD.

CONCLUSION

This study deepens our understanding of the field of BPD pathogenesis by demonstrating an association between vitamin D/E deficiency and BPD severity, suggesting that vitamin D and E might have potential clinical value in the prognosis and treatment of BPD.

Association of Chorioamnionitis With Bronchopulmonary Dysplasia Among Preterm Infants: A Systematic Review, Meta-analysis, and Metaregression

Importance

Bronchopulmonary dysplasia (BPD), a chronic lung disease of prematurity, remains one of the major and most common complications of very preterm birth. Insight into factors associated with the pathogenesis of BPD is key to improving its prevention and treatment.

Objective

To perform a systematic review, meta-analysis, and metaregression of clinical studies exploring the association between chorioamnionitis (CA) and BPD in preterm infants.

Data Sources

PubMed and Embase were searched without language restriction (last search, October 1, 2018). Key search terms included bronchopulmonary dysplasia, chorioamnionitis, and risk factors.

Study Selection

Included studies were peer-reviewed studies examining preterm (<37 weeks' gestation) or very low-birth-weight (<1500 g) infants and reporting primary data that could be used to measure the association between exposure to CA and the development of BPD.

Data Extraction and Synthesis

The Meta-analysis of Observational Studies in Epidemiology (MOOSE) guideline was followed. Data were independently extracted by 2 researchers. A random-effects model was used to calculate odds ratios (ORs) and 95% CIs. Heterogeneity in effect size across studies was studied using multivariate, random-effects metaregression analysis.

Main Outcomes and Measures

The primary outcome was BPD, defined as supplemental oxygen requirement on postnatal day 28 (BPD28) or at the postmenstrual age of 36 weeks (BPD36). Covariates considered as potential confounders included differences between CA-exposed and CA-unexposed infants in gestational age, rates of respiratory distress syndrome (RDS), exposure to antenatal corticosteroids, and rates of early- and late-onset sepsis.

Results

A total of 3170 potentially relevant studies were found, of which 158 met the inclusion criteria (244 096 preterm infants, 20 971 CA cases, and 24 335 BPD cases). Meta-analysis showed that CA exposure was significantly associated with BPD28 (65 studies; OR, 2.32; 95% CI, 1.88-2.86; P < .001; heterogeneity: I2 = 84%; P < .001) and BPD36 (108 studies; OR, 1.29; 95% CI, 1.17-1.42; P < .001; heterogeneity: I2 = 63%; P < .001). The association between CA and BPD remained significant for both clinical and histologic CA. In addition, significant differences were found between CA-exposed and CA-unexposed infants in gestational age, birth weight, odds of being small for gestational age, exposure to antenatal corticosteroids, and early- and late-onset sepsis. Chorioamnionitis was not significantly associated with RDS (48 studies; OR, 1.10; 95% CI, 0.92-1.34; P = .24; heterogeneity: I2 = 90%; P < .001), but multivariate metaregression analysis with backward elimination revealed that a model combining the difference in gestational age and the odds of RDS was associated with 64% of the variance in the association between CA and BPD36 across studies.

Conclusions and Relevance

The results of this study confirm that among preterm infants, exposure to CA is associated with a higher risk of developing BPD, but this association may be modulated by gestational age and risk of RDS.

Exploring clinical, echocardiographic and molecular biomarkers to predict bronchopulmonary dysplasia

Introduction

Bronchopulmonary dysplasia (BPD) is the most common chronic lung disease in childhood, related to prematurity, and the most common cause of pulmonary hypertension (PH) secondary to pulmonary disease in children. Moderate and severe BPD have a worse outcome and relate more frequently with PH. The prediction of moderate or severe BPD development in extremely premature newborns is vital to implement preventive strategies. Starting with the hypothesis that molecular biomarkers were better than clinical and echocardiographic factors, this study aims to explore the ability of clinical, echocardiographic and analytical variables to predict moderate or severe BPD in a cohort of extremely preterm infants.

Patients and methods

We designed a prospective longitudinal study, in which we followed a cohort of preterm newborns (gestational age <28 weeks and weight ≤ 1250 grams). In these newborns we recorded weekly clinical and echocardiographic variables as well as blood and tracheal aspirate samples, to analyze molecular biomarkers (IL-6, IL-1, IP10, uric acid, HGF, endothelin-1, VEGF, CCL5). Variables and samples were collected since birth up to week 36 (postmenstrual age), time-point at which the diagnosis of BPD is established.

Results

We included 50 patients with a median gestational age of 26 weeks (IQR 25–27) and weight of 871 g (SD 161,0) (range 590-1200g). Three patients were excluded due to an early death. Thirty-five patients (74.5%) developed BPD (mild n = 14, moderate n = 15, severe n = 6). We performed a logistic regression in order to identify risk factors for moderate or severe BPD. We compared two predictive models, one with two variables (mechanical ventilation and inter-ventricular septum flattening), and another-one with an additional molecular biomarker (ET-1).

Conclusions

The combination of clinical and echocardiographic variables is a valuable tool for determining the risk of BPD. We find the two variable model (mechanical ventilation and echocardiographic signs of PH) more practical for clinical and research purposes. Future research on BPD prediction should be oriented to explore the potential role of ET-1.

Preventing bronchopulmonary dysplasia: new tools for an old challenge

Bronchopulmonary dysplasia (BPD) is the most prevalent chronic lung disease in infants and presents as a consequence of preterm birth. Due to the lack of effective preventive and treatment strategies, BPD currently represents a major therapeutic challenge that requires continued research efforts at the basic, translational, and clinical levels. However, not all very low birth weight premature babies develop BPD, which suggests that in addition to known gestational age and intrauterine and extrauterine risk factors, other unknown factors must be involved in this disease's development. One of the main goals in BPD research is the early prediction of very low birth weight infants who are at risk of developing BPD in order to initiate the adequate preventive strategies. Other benefits of determining the risk of BPD include providing prognostic information and stratifying infants for clinical trial enrollment. In this article, we describe new opportunities to address BPD's complex pathophysiology by identifying prognostic biomarkers and develop novel, complex in vitro human lung models in order to develop effective therapies. These therapies for protecting the immature lung from injury can be developed by taking advantage of recent scientific progress in -omics, 3D organoids, and regenerative medicine.

Preeclampsia predicts higher incidence of bronchopulmonary dysplasia

INTRODUCTION

It is not known whether very preterm infants born to preeclamptic women have worse outcomes than those delivered preterm for other causes.

OBJECTIVE

We assessed the association between preeclampsia (PE) and the neonatal morbidity and mortality of very preterm infants.

METHODS

Over 2015 and 2016, 11 collaborating Portuguese level III NICUs prospectively enrolled a cohort of mothers with or without PE who delivered liveborn premature infants between 24 and 30 completed weeks of gestation. Data on neonatal morbidities were collected and their association to PE was assessed.

RESULTS

The final cohort consisted of 410 mothers who delivered 494 preterm infants. Infants from PE mothers weighed less than those of non-PE mothers (819 ± 207 g vs. 989 ± 256 g, p < 0.0001). Incidences of respiratory distress syndrome, patent ductus arteriosus, early and nosocomial sepsis, necrotizing enterocolitis, pneumonia, meningitis, retinopathy of prematurity, intraventricular hemorrhage, periventricular infarction, periventricular leukomalacia, and mortality did not differ significantly between infants of PE or non-PE mothers. Incidence of bronchopulmonary dysplasia (BPD-defined as oxygen dependency at 36 weeks) was higher in PE infants compared with non-PE infants by both univariate and multivariate logistic regression (p = 0.007).

CONCLUSION

We conclude that, when controlling for gestational age, maternal PE results in higher incidence of only BPD among preterm Portuguese infants.

Respiratory Care for the Ventilated Neonate

Invasive ventilation is often necessary for the treatment of newborn infants with respiratory insufficiency. The neonatal patient has unique physiological characteristics such as small airway caliber, few collateral airways, compliant chest wall, poor airway stability, and low functional residual capacity. Pathologies affecting the newborn's lung are also different from many others observed later in life. Several different ventilation modes and strategies are available to optimize mechanical ventilation and to prevent ventilator-induced lung injury. Important aspects to be considered in ventilating neonates include the use of correct sized endotracheal tube to minimize airway resistance and work of breathing, positioning of the patient, the nursing care, respiratory kinesiotherapy, sedation and analgesia, and infection prevention, namely, the ventilator-associated pneumonia and nosocomial infection, as well as prevention and treatment of complications such as air leaks and pulmonary hemorrhage. Aspects of ventilation in patients under ECMO (extracorporeal membrane oxygenation) and in palliative care are of increasing interest nowadays. Online pulmonary mechanics and function testing as well as capnography are becoming more commonly used. Echocardiography is now a routine in most neonatal units. Near infrared spectroscopy (NIRS) is an attractive tool potentially helping in preventing intraventricular hemorrhage and periventricular leukomalacia. Lung ultrasound is an emerging tool of diagnosis and can be of added value in helping monitoring the ventilated neonate. The aim of this scientific literature review is to address relevant aspects concerning the respiratory care and monitoring of the invasively ventilated newborn in order to help physicians to optimize the efficacy of care.

Morbidity and mortality of coagulase-negative staphylococcal sepsis in very-low-birth-weight infants

BACKGROUND

Coagulase-negative staphylococci (CoNS) are the most common cause of late-onset sepsis in the neonatal intensive care unit (NICU) and usually require vancomycin treatment. Our objective was to determine whether CoNS are associated with neonatal morbidity and mortality.

METHODS

This was a retrospective cohort study of very-low-birth-weight (VLBW, ≤ 1500 g) infants from 1989 to 2015. Exclusion criteria were major congenital anomaly or death within 72 h. CoNS was considered a pathogen if recovered from ≥ 2 cultures, or 1 culture if treated for ≥ 5 days and signs of sepsis were present. Logistic regression was used to examine factors associated with morbidity and mortality.

RESULTS

Of 2242 VLBW infants, 285 (12.7%) had late-onset sepsis. CoNS (125, 44%), Staphylococcus aureus (52, 18%), and Escherichia coli (36, 13%) were the most commonly recovered organisms. In multivariate analysis, CoNS sepsis was not associated with mortality [OR 0.6 (95% CI 0.2-2.6)), but sepsis with other organisms was [OR 4.5 (95% CI 2.6-8.0)]. CoNS sepsis was associated with longer hospitalization but not risk for bronchopulmonary dysplasia, intraventricular hemorrhage, or retinopathy of prematurity.

CONCLUSION

CoNS sepsis was not associated with mortality or morbidities other than length of stay. These findings support vancomycin-reduction strategies in the NICU.