Respiratory characteristics of infants with pulmonary hypoplasia syndrome following preterm rupture of membranes: a preliminary study for establishing clinical diagnostic criteria

Predicting Clinical Outcomes of Severe Bronchopulmonary Dysplasia through New Definitions and Phenotypes

This study aimed to compare the accuracy of three newly proposed definitions of bronchopulmonary dysplasia (BPD) in predicting outcomes, and to investigate the impact of large airway versus parenchymal versus vascular BPD phenotypes on BPD outcomes.Retrospective chart review of 100 infants with severe BPD discharged from a Children's hospital between 2020 and 2021. Multivariable models evaluated the associations between BPD definitions and phenotypes with tracheostomy and death at 6 months and 1 year after NICU discharge. Secondary outcomes included the need for respiratory support, the use of pulmonary medications, and the need for long-term gastrostomy feeding.Neonatal research network (NRN) and BPD collaborative criteria best-predicted outcomes associated with tracheostomy and/or death (p < 0.001). Among the three BPD phenotypes, large airway disease was independently associated with death or tracheostomy (odds ratios [OR]: 10.5; 95% confidence interval [CI]: 1.6, 68.1). The combination of all three phenotypes was also associated with death or tracheostomy (OR: 9.8; 95% CI: 1.0, 93.5). Both NRN and BPD collaborative definitions showed an association with the need for respiratory support, medication use, and need for long-term gastrostomy tube feeding. Among the 29 infants for whom complete information was available, 18 (62%), 20 (69%), and 18 (62%) had parenchymal, central airway and pulmonary vascular phenotype, respectively.Our results indicate that newer definitions of BPD may better predict the severity of BPD and the need for long-term invasive ventilation support compared with the 2001 National Institute of Health definition of BPD phenotypes impacting mortality and short-term outcomes. These data may be useful for counseling families and developing phenotype-based individualized treatment plans. · The current definition of BPD has limitations.. · New definitions of BPD better predict outcomes.. · BPD phenotypes can better predict outcomes..

Bilateral renal agenesis: fetal intervention and outcomes

Bilateral renal agenesis (BRA) is a fetal anomaly which leads to anhydramnios and resultant pulmonary hypoplasia. Historically, this anomaly was universally fatal early in the neonatal period due to the severity of the associated lung disease. Over the last 30 years, innovations in fetal therapies-specifically, serial amnioinfusions-have led to instances of infant pulmonary survival and initiation of postnatal dialysis, raising the possibility that early neonatal death may not be inevitable. Amnioinfusions are not without risk, and maternal complications can include prelabor rupture of membranes, preterm labor, infection, and bleeding. The data detailing neonatal outcomes are still limited and actively being collected. Two case series and one non-randomized clinical trial have supplied most of the known outcome data for infants with BRA after prenatal amnioinfusion. Although there are survivors reported in the literature, mortality remains high, with many deaths in infancy due to dialysis-associated sepsis. In addition, previously unknown morbidities have been documented in these infants, including neurologic injury. These challenges, in addition to the mechanical difficulties of providing dialysis to extremely small infants, can result in significant burdens for patients and their caregivers and moral distress for the health care team. The present review aims to explain the pathophysiology of BRA, detail the historical context and rationale for serial amnioinfusions to treat the pulmonary insufficiency associated with BRA, describe the available data regarding outcomes of infants born following prenatal amnioinfusions, discuss ethical issues surrounding this fetal intervention, and describe critical aspects of prenatal counseling for patients considering the intervention.

Contemporary neonatal outcome following rupture of membranes prior to 25 weeks with prolonged oligohydramnios

BACKGROUND

Prolonged oligohydramnios following early preterm prelabour rupture of membranes (PPROM) is traditionally associated with high neonatal mortality and significant risk of pulmonary hypoplasia. However, recent evidence points to an apparent improvement in outcome.

AIMS

To document current neonatal outcomes following rupture of membranes prior to 25 weeks with severe persistent oligohydramnios and a latency to delivery of at least 14 days.

METHODS

A retrospective case note analysis over a 28-month period at Saint Luc University Hospital, Brussels.

RESULTS

From 23 pregnancies that were complicated by PPROM prior to 25 weeks, 15 infants were born after 24 weeks with a latency of more than 14 days and persistent oligohydramnios. Nine infants (60%) had severe respiratory failure and clinical signs compatible with pulmonary hypoplasia. Seven of these infants (78%) responded to high frequency ventilation and inhaled nitric oxide therapy with good clinical outcome but two died from severe respiratory failure. Five infants showed no clinical signs of pulmonary hypoplasia and responded to conventional neonatal management. One of these infants died at 77 days of age of necrotising enterocolitis. One infant was not resuscitated and died within minutes of birth, following prior discussion with the perinatal team and the parents. Survivors in this high-risk group (73%) had low morbidity at the time of discharge.

SUMMARY

The favourable neonatal survival and morbidity figures are in keeping with recent published evidence. This study confirms improved outcome even amongst the highest risk infants with documented persistent oligohydramnios.

Effects of antenatal corticosteroid treatment on pulmonary ventilation and circulation in neonatal lambs with hypoplastic lungs

Our aim was to determine whether antenatal corticosteroids improve perinatal adaptation of the pulmonary circulation in lambs with lung hypoplasia (LH). LH was induced in 12 ovine fetuses between 105 and 140 days gestation (term approximately 147 days); in 6 of these the ewe was given a single dose of betamethasone (11.4 mg im) 24 hr before delivery (LH + B). All lambs, including a control group (n = 6), were delivered at approximately 140 days and ventilated for 2 hr during which arterial pressures, pulmonary blood flow (PBF), and ventilating pressure and flow were recorded. During ventilation, respiratory system compliance was lower in both LH + B and LH groups than in controls. Pulmonary vascular resistance (PVR) was lower in LH + B lambs than in LH lambs and similar to controls; PBF was reduced in LH lambs but was restored to control levels by betamethasone. The mean density of small arteries of LH + B lambs was similar to that of LH lambs (P = 0.06) and lower than in controls; the thickness of the media of small pulmonary arteries from LH + B lambs was similar to that in LH lambs and thicker than in controls. VEGF mRNA levels were not different between groups. PDGF mRNA levels in LH + B lambs were higher than in LH lambs; a similar trend (P = 0.06) was seen for PECAM-1. SP-C mRNA levels were greater in both LH and LH + B lambs than in controls. Effects of betamethasone were greater on indices of pulmonary circulation than ventilation. We conclude that a single dose of maternal betamethasone 24 hr prior to birth has significant favorable effects on the postnatal adaptation of the pulmonary circulation in lambs with LH.