Rehospitalization and growth of infants with bronchopulmonary dysplasia: a matched control study

Laryngeal mask airway surfactant administration for prevention of morbidity and mortality in preterm infants with or at risk of respiratory distress syndrome

BACKGROUND

Laryngeal mask airway surfactant administration (S-LMA) has the potential benefit of surfactant administration whilst avoiding endotracheal intubation and ventilation, ventilator-induced lung injury and bronchopulmonary dysplasia (BPD).

OBJECTIVES

To evaluate the benefits and harms of S-LMA either as prophylaxis or treatment (rescue) compared to placebo, no treatment, or intratracheal surfactant administration via an endotracheal tube (ETT) with the intent to rapidly extubate (InSurE) or extubate at standard criteria (S-ETT) or via other less-invasive surfactant administration (LISA) methods on morbidity and mortality in preterm infants with or at risk of respiratory distress syndrome (RDS).

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, and three trial registries in December 2022.

SELECTION CRITERIA

Randomised controlled trials (RCTs), cluster- or quasi-RCTs of S-LMA compared to placebo, no treatment, or other routes of administration (nebulised, pharyngeal instillation of surfactant before the first breath, thin endotracheal catheter surfactant administration or intratracheal surfactant instillation) on morbidity and mortality in preterm infants at risk of RDS. We considered published, unpublished and ongoing trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion and extracted data. We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included eight trials (seven new to this update) recruiting 510 newborns. Five trials (333 infants) compared S-LMA with surfactant administration via ETT with InSurE. One trial (48 infants) compared S-LMA with surfactant administration via ETT with S-ETT, and two trials (129 infants) compared S-LMA with no surfactant administration. We found no studies comparing S-LMA with LISA techniques or prophylactic or early S-LMA. S-LMA versus surfactant administration via InSurE S-LMA may have little or no effect on the composite outcome of death or BPD at 36 weeks' postmenstrual age (risk ratio (RR) 1.50, 95% confidence interval (CI) 0.27 to 8.34, I 2 = not applicable (NA) as 1 study had 0 events; risk difference (RD) 0.02, 95% CI -0.07 to 0.10; I 2 = 0%; 2 studies, 110 infants; low-certainty evidence). There may be a reduction in the need for mechanical ventilation at any time (RR 0.53, 95% CI 0.36 to 0.78; I 2 = 27%; RD -0.14, 95% CI -0.22 to -0.06, I 2 = 89%; number needed to treat for an additional beneficial outcome (NNTB) 7, 95% CI 5 to 17; 5 studies, 333 infants; low-certainty evidence). However, this was limited to four studies (236 infants) using analgesia or sedation for the InSurE group. There was little or no difference for air leak during first hospitalisation (RR 1.39, 95% CI 0.65 to 2.98; I 2 = 0%; 5 studies, 333 infants (based on 3 studies as 2 studies had 0 events); low-certainty evidence); BPD among survivors to 36 weeks' PMA (RR 1.28, 95% CI 0.47 to 3.52; I 2 = 0%; 4 studies, 264 infants (based on 3 studies as 1 study had 0 events); low-certainty evidence); or death (all causes) during the first hospitalisation (RR 0.28, 95% CI 0.01 to 6.60; I 2 = NA as 2 studies had 0 events; 3 studies, 203 infants; low-certainty evidence). Neurosensory disability was not reported. Intraventricular haemorrhage ( IVH) grades III and IV were reported among the study groups (1 study, 50 infants). S-LMA versus surfactant administration via S-ETT No study reported death or BPD at 36 weeks' PMA. S-LMA may reduce the use of mechanical ventilation at any time compared with S-ETT (RR 0.47, 95% CI 0.31 to 0.71; RD -0.54, 95% CI -0.74 to -0.34; NNTB 2, 95% CI 2 to 3; 1 study, 48 infants; low-certainty evidence). We are very uncertain whether S-LMA compared with S-ETT reduces air leak during first hospitalisation (RR 2.56, 95% CI 0.11 to 59.75), IVH grade III or IV (RR 2.56, 95% CI 0.11 to 59.75) and death (all causes) during the first hospitalisation (RR 0.17, 95% CI 0.01 to 3.37) (1 study, 48 infants; very low-certainty evidence). No study reported BPD to 36 weeks' PMA or neurosensory disability. S-LMA versus no surfactant administration Rescue surfactant could be used in both groups. There may be little or no difference in death or BPD at 36 weeks (RR 1.65, 95% CI 0.85 to 3.22; I 2 = 58%; RD 0.08, 95% CI -0.03 to 0.19; I 2 = 0%; 2 studies, 129 infants; low-certainty evidence). There was probably a reduction in the need for mechanical ventilation at any time with S-LMA compared with nasal continuous positive airway pressure without surfactant (RR 0.57, 95% CI 0.38 to 0.85; I 2 = 0%; RD -0.24, 95% CI -0.40 to -0.08; I 2 = 0%; NNTB 4, 95% CI 3 to 13; 2 studies, 129 infants; moderate-certainty evidence). There was little or no difference in air leak during first hospitalisation (RR 0.65, 95% CI 0.23 to 1.88; I 2 = 0%; 2 studies, 129 infants; low-certainty evidence) or BPD to 36 weeks' PMA (RR 1.65, 95% CI 0.85 to 3.22; I 2 = 58%; 2 studies, 129 infants; low-certainty evidence). There were no events in either group for death during the first hospitalisation (1 study, 103 infants) or IVH grade III and IV (1 study, 103 infants). No study reported neurosensory disability.

AUTHORS' CONCLUSIONS

In preterm infants less than 36 weeks' PMA, rescue S-LMA may have little or no effect on the composite outcome of death or BPD at 36 weeks' PMA. However, it may reduce the need for mechanical ventilation at any time. This benefit is limited to trials reporting the use of analgesia or sedation in the InSurE and S-ETT groups. There is low- to very-low certainty evidence for no or little difference in neonatal morbidities and mortality. Long-term outcomes are largely unreported. In preterm infants less than 32 weeks' PMA or less than 1500 g, there are insufficient data to support or refute the use of S-LMA in clinical practice. Adequately powered trials are required to determine the effect of S-LMA for prevention or early treatment of RDS in extremely preterm infants. S-LMA use should be limited to clinical trials in this group of infants.

Indications and practice of home invasive mechanical ventilation in children

BACKGROUND

Developments and technological advances in neonatal and pediatric intensive care units have led to a prolonged life expectancy of pediatric patients with chronic respiratory failure. Therefore, the number of hemodynamically stable pediatric patients with chronic respiratory failure who need mechanical ventilator assistance throughout the day has significantly increased.

AIMS

Numerous conditions, including parenchymal lung diseases, airway disorders, neuromotor disorders, or respiratory defects, can lead to chronic respiratory failure. For individuals who cannot tolerate non-invasive mechanical ventilation (NIMV), invasive mechanical ventilation (IMV) is the only suitable choice. Due to increasing need, mechanical ventilator technology is continuously evolving.

RESULTS

As a result of this process, home-type mechanical ventilators have been produced for patients requiring long-term IMV. Patients with chronic respiratory failure can be safely monitored at home with these ventilators.

DISCUSSION

Home follow-up of these patients has many benefits such as an increase in general quality of life and a positive contribution to their emotional and cognitive development.

CONCLUSION

In this compilation, indications for home-based IMV, features of home invasive mechanical ventilators (HMVs), patient monitoring, and the detailed advantages of using IMV at home will be elucidated.

Outpatient Respiratory Management of Infants, Children, and Adolescents with Post-Prematurity Respiratory Disease: An Official American Thoracic Society Clinical Practice Guideline

Background: Premature birth affects millions of neonates each year, placing them at risk for respiratory disease due to prematurity. Bronchopulmonary dysplasia is the most common chronic lung disease of infancy, but recent data suggest that even premature infants who do not meet the strict definition of bronchopulmonary dysplasia can develop adverse pulmonary outcomes later in life. This post-prematurity respiratory disease (PPRD) manifests as chronic respiratory symptoms, including cough, recurrent wheezing, exercise limitation, and reduced pulmonary function. This document provides an evidence-based clinical practice guideline on the outpatient management of infants, children, and adolescents with PPRD. Methods: A multidisciplinary panel of experts posed questions regarding the outpatient management of PPRD. We conducted a systematic review of the relevant literature. The Grading of Recommendations, Assessment, Development, and Evaluation approach was used to rate the quality of evidence and the strength of the clinical recommendations. Results: The panel members considered the strength of each recommendation and evaluated the benefits and risks of applying the intervention. In formulating the recommendations, the panel considered patient and caregiver values, the cost of care, and feasibility. Recommendations were developed for or against three common medical therapies and four diagnostic evaluations in the context of the outpatient management of PPRD. Conclusions: The panel developed recommendations for the outpatient management of patients with PPRD on the basis of limited evidence and expert opinion. Important areas for future research were identified.

Growth failure of very low birth weight infants during the first 3 years: A Korean neonatal network

We aimed to evaluate risk factors for growth failure in very low birth weight (VLBW) infants at 18-24 months of corrected age (follow-up1, FU1) and at 36 months of age (follow-up2, FU2). In this prospective cohort study, a total of 2,943 VLBW infants from the Korean Neonatal Network between 2013 and 2015 finished follow-up at FU1. Growth failure was defined as a z-score below -1.28. Multiple logistic regression was used to analyze risk factors for growth failure after dividing the infants into small for gestational age (SGA) and appropriate for gestational age (AGA) groups. Overall, 18.7% of infants were SGA at birth. Growth failure was present in 60.0% at discharge, 20.3% at FU1, and 35.2% at FU2. Among AGA infants, male sex, growth failure at discharge, periventricular leukomalacia, treatment of retinopathy of prematurity, ventriculoperitoneal shunt status and treatment of rehabilitation after discharge were independent risk factors for growth failure at FU1. Among SGA infants, lower birth weight, pregnancy-induced hypertension, and treatment of rehabilitation after discharge were independent risk factors for growth failure at FU1. Mean weight z-score graphs from birth to 36 month of age revealed significant differences between SGA and non-SGA and between VLBW infants and extremely low birth weight infants. Growth failure remains an issue, and VLBW infants with risk factors should be closely checked for growth and nutrition.

Neighborhood Disadvantage and Early Respiratory Outcomes in Very Preterm Infants with Bronchopulmonary Dysplasia

OBJECTIVE

To investigate the impact of neighborhood conditions on respiratory-related hospital admissions in the first year after discharge from the neonatal unit in a population of infants born very preterm with bronchopulmonary dysplasia (BPD).

STUDY DESIGN

Very preterm infants (gestational age <33 weeks) who had BPD at 36 weeks postconceptional age and who received follow-up in a French regional medical network were included. Socioeconomic context was estimated using a neighborhood-based Socioeconomic Deprivation Index. Poisson regression analysis was used to identify risk factors associated with rehospitalization.

RESULTS

The study included 423 infants with a mean gestational age of 27 ± 2 weeks and mean birth weight of 941 ± 277 g; 51% of the population lived in a disadvantaged area. The hospital admission rate was increased by 8.8% for infants living in affluent areas and by 24% for those living in disadvantaged areas (P <.01) and reached 30% in extremely preterm infants from disadvantaged areas. After adjusting for perinatal characteristics, home oxygen therapy, and season of birth, the respiratory-related hospitalization rate was almost 3-fold higher in infants living in disadvantaged areas, with an adjusted incidence rate ratio of 2.79 (95% CI, 1.29-6.09; P <.01).

CONCLUSIONS

Disadvantaged neighborhoods adversely impact early respiratory outcomes in infants born very preterm with BPD. The social context should be considered in routine follow-up care of children born preterm. Further studies investigating the underlying mechanisms are warranted for implementing preventive strategies.

Advances in extracorporeal membrane oxygenator design for artificial placenta technology

Extreme prematurity, defined as a gestational age of fewer than 28 weeks, is a significant health problem worldwide. It carries a high burden of mortality and morbidity, in large part due to the immaturity of the lungs at this stage of development. The standard of care for these patients includes support with mechanical ventilation, which exacerbates lung pathology. Extracorporeal life support (ECLS), also called artificial placenta technology when applied to extremely preterm (EPT) infants, offers an intriguing solution. ECLS involves providing gas exchange via an extracorporeal device, thereby doing the work of the lungs and allowing them to develop without being subjected to injurious mechanical ventilation. While ECLS has been successfully used in respiratory failure in full-term neonates, children, and adults, it has not been applied effectively to the EPT patient population. In this review, we discuss the unique aspects of EPT infants and the challenges of applying ECLS to these patients. In addition, we review recent progress in artificial placenta technology development. We then offer analysis on design considerations for successful engineering of a membrane oxygenator for an artificial placenta circuit. Finally, we examine next-generation oxygenators that might advance the development of artificial placenta devices.

Long term outcomes in chronic lung disease requiring tracheostomy and chronic mechanical ventilation

Bronchopulmonary dysplasia (BPD) is the most common serious complication associated with preterm birth. Infants with severe BPD often require prolonged and intensive pulmonary care. Among those with the most severe lung disease, this care may include tracheostomy and long-term invasive mechanical ventilation. Although there is a plethora of data on long term respiratory and developmental outcomes of BPD survivors, relevant information on BPD survivors requiring chronic respiratory failure are limited. When compared to those born at term gestation, infants with BPD requiring chronic ventilation are at increased risk of hospitalizations and develop more frequent lower respiratory infections. In childhood and young adulthood, spirometry often shows an obstructive flow pattern. From a neurodevelopmental standpoint, the short-term outcomes appear optimistic, with improvement in growth and increased participation in development-promoting activities. Nonetheless, children born prematurely are vulnerable for long term cognitive, educational and behavioral impairments. BPD is an additional risk factor which exacerbates these deficits, thus contributing to lifelong neurodevelopmental impairments of prematurity.

Home Oxygen and 2-Year Outcomes of Preterm Infants With Bronchopulmonary Dysplasia

OBJECTIVES

To compare medical and developmental outcomes over the first 2 years of life in extremely preterm infants with bronchopulmonary dysplasia (BPD) who were discharged on supplemental oxygen via nasal cannula with outcomes of infants with a similar severity of respiratory illness who were discharged breathing in room air.

METHODS

We performed a propensity score-matched cohort study. Eligible infants were born at <27 weeks' gestation, were receiving supplemental oxygen or respiratory support at 36 weeks' postmenstrual age, and were assessed at 18 to 26 months' corrected age. Study outcomes included growth, resource use, and neurodevelopment between discharge and follow-up. Outcomes were compared by using multivariable models adjusted for center and age at follow-up.

RESULTS

A total of 1039 infants discharged on supplemental oxygen were propensity score matched 1:1 to infants discharged breathing in room air. Infants on oxygen had a marginal improvement in weight z score (adjusted mean difference 0.11; 95% confidence interval [CI] 0.00 to 0.22), with a significantly improved weight-for-length z score (adjusted mean difference 0.13; 95% CI 0.06 to 0.20) at 22 to 26 months' corrected age. Infants on oxygen were more likely to be rehospitalized for respiratory illness (adjusted relative risk 1.33; 95% CI 1.16 to 1.53) and more likely to use respiratory medications and equipment. Rates of neurodevelopmental impairment were similar between the groups.

CONCLUSIONS

In this matched cohort of infants with BPD, postdischarge oxygen was associated with marginally improved growth and increased resource use but no difference in neurodevelopmental outcomes. Ongoing and future trials are critical to assess the efficacy and safety of postdischarge supplemental oxygen for infants with BPD.

The Impact of Bronchopulmonary Dysplasia on Childhood Outcomes

The rate of bronchopulmonary dysplasia (BPD) in preterm infants is increasing; this trend reflects, in part, improved survival among extremely premature infants. BPD is associated with adverse developmental and medical outcomes in early childhood and at least through school age. Therefore, BPD imposes a significant burden on infants and children, their families, and society. Many interventions to decrease BPD and the sequelae of BPD have been studied; few to date have been proved to decrease both BPD and later disability.

The influence of gender on respiratory outcomes in children with bronchopulmonary dysplasia during the first 3 years of life

INTRODUCTION

Since premature males are more likely to be diagnosed with bronchopulmonary dysplasia we hypothesized that differences in respiratory outcomes after initial hospital discharge and during the first 3 years of life would exist between females and males diagnosed with BPD.

METHODS

Subjects with the diagnosis of BPD were recruited from the Johns Hopkins Bronchopulmonary Dysplasia Clinic between 2008 and 2014. Clinical features were assessed through chart review (n = 482). Respiratory morbidities were assessed by caregiver questionnaires at clinic visits (n = 429), including emergency department visits, hospital admissions, systemic steroid use, and antibiotic use for respiratory reasons since the last BPD clinic visit or after initial hospital discharge if assessed at the first visit.

RESULTS

Male infants weighed significantly more at birth, had higher birth weight percentiles and were more likely to be non-white compared to female infants. The frequency of ever acute care use was 36.9% for emergency department visits, 27.4% for hospital admissions, 36.9% for systemic steroid use, and 40.5% for antibiotic use for a respiratory illness. No differences in respiratory morbidities were found between males and females. Females however, tended to be weaned from supplemental oxygen over 3 months later than males.

CONCLUSIONS

Compared to females with BPD, males were more likely to weigh more, have higher birth weight percentiles and be non-white. After initial hospital discharge, there were no difference in respiratory morbidities between males and females with BPD. Female infants however were more likely to be weaned from supplemental oxygen at a later age than male infants. Pediatr Pulmonol. 2017;52:217-224. © 2016 Wiley Periodicals, Inc.

Bronchopulmonary Dysplasia Within and Beyond the Neonatal Unit

BACKGROUND

Bronchopulmonary dysplasia (BPD), also known as chronic lung disease of prematurity or chronic neonatal lung disease, is a major cause of respiratory illness in premature babies. Newborn babies survive at gestational ages of 23 to 26 weeks, earlier than when BPD was first described. New mechanisms of lung injury have therefore emerged and the clinical and pathological characteristics of pulmonary involvement have changed.

PURPOSE

Improved neonatal intensive care unit modalities have increased survival rates; the overall prevalence of the condition, however, has not changed. Management of evolving BPD aims at minimizing lung injury. Management of established, especially severe BPD, still poses significant clinical challenge as these babies need long-term oxygen therapy (LTOT) for variable length of time. We aim to give an overview of management of established BPD with particular focus on weaning home oxygen therapy at our local center in the United Kingdom.

SEARCH AND RESULTS

On the basis of most recent evidence, we concluded that an integrated pathway for managing babies on LTOT is very important after discharge from neonatal unit.

IMPLICATIONS FOR PRACTICE

A structured weaning pathway for premature babies on home oxygen improves outcome.

IMPLICATIONS FOR RESEARCH

The management of severe BPD and related complications, particularly during the first 2 years of life, remains a continuing challenge for parents and healthcare providers. The most beneficial respiratory support strategy to minimize lung injury and/or promote lung healing remains unclear and requires further investigation.

Home Mechanical Ventilation in Children

The number of children dependent on home mechanical ventilation has been reported to be increasing in many countries around the world. Home mechanical ventilation has been well accepted as a standard treatment of children with chronic respiratory failure. Some children may need mechanical ventilation as a lifelong therapy. To send mechanically ventilated children back home may be more difficult than adults. However, relatively better outcomes have been demonstrated in children. Children could be safely ventilated at home if they are selected and managed properly. Conditions requiring home ventilation include increased respiratory load from airway or lung pathologies, ventilatory muscle weakness and failure of neurologic control of ventilation. Home mechanical ventilation should be considered when the patient develops progressive respiratory failure or intractable failure to wean mechanical ventilation. Polysomnography or overnight pulse oximetry plus capnometry are used to detect nocturnal hypoventilation in early stage of respiratory failure. Ventilator strategy including non-invasive and invasive approach should be individualized for each patient. The author strongly believes that parents and family members are able to take care of their child at home if they are trained and educated effectively. A good team work with dedicated members is the key factor of success.

High Risk Infants Follow-Up: A Case Study in Iran

Background. A follow-up program for high risk infants was initiated in Alzahra Maternity Hospital in Tabriz city, Iran, in 2013. The aim of this paper is to give a brief report of the program. Material and Methods. Two groups of high risk neonates were studied. The first group comprising 509 infants received services in Alzahra Maternity Hospital implemented by the follow-up program. This included a full package for family to look after high risk infant and periodic clinical evaluation at two and four weeks after birth and then two, three, four, five, and six months later again. The second group including 131 infants in Taleqani Maternity Hospital received routine services after birth with no specific follow-up care. Results. Some anthropometric indices showed a significant improvement in the intervention hospital compared to control group. These included the following: head circumference at first and second months; weight in the first, fourth, fifth, and sixth months; and height in sixth month only. Clinical evaluation of infants showed an improvement for some of the medical conditions. Conclusion. Follow-up care program for a minimum of six months after discharge from maternity hospitals may help to avoid adverse and life threatening consequences in high risk infants.

Hair nicotine levels in children with bronchopulmonary dysplasia

BACKGROUND

Tobacco smoke exposure (TSE) may increase respiratory morbidities in young children with bronchopulmonary dysplasia (BPD). Rapid respiratory rates, close proximity to a smoking caregiver, and increased dermal absorption of tobacco smoke components can contribute to systemic exposure. In this study, hair nicotine levels were used as a biomarker of chronic TSE in young children with BPD to determine if hair nicotine levels correlate with caregiver self-report of TSE and respiratory morbidities.

METHODS

From 2012 to 2014, hair nicotine levels were measured from consecutive children seen in a BPD outpatient clinic and compared with caregiver questionnaires on household smoking. The relationship between respiratory morbidities and self-reported TSE or hair nicotine level was assessed.

RESULTS

The mean hair nicotine level from 117 children was 3.1 ± 13.2 ng/mg. Hair nicotine levels were significantly higher in children from smoking households by caregiver self-report compared with caregivers who reported no smoking (8.2 ± 19.7 ng/mg vs 1.8 ± 10.7; P < .001). In households that reported smoking, hair nicotine levels were higher in children with a primary caregiver who smoked compared with a primary caregiver who did not smoke. Among children with BPD who required respiratory support (n = 50), a significant association was found between higher log hair nicotine levels and increased hospitalizations and limitation of activity.

CONCLUSIONS

Chronic TSE is common in children with BPD, with hair nicotine levels being more likely to detect TSE than caregiver self-report. Hair nicotine levels were also a better predictor of hospitalization and activity limitation in children with BPD who required respiratory support at outpatient presentation.

Epidemiology of bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is among the most common and serious sequelae of preterm birth. BPD affects at least one-quarter of infants born with birth weights less than 1500 g. The incidence of BPD increases with decreasing gestational age and birth weight. Additional important risk factors include intrauterine growth restriction, sepsis, and prolonged exposure to mechanical ventilation and supplemental oxygen. The diagnosis of BPD predicts multiple adverse outcomes including chronic respiratory impairment and neurodevelopmental delay. This review summarizes the diagnostic criteria, incidence, risk factors, and long-term outcomes of BPD.

Secondhand smoke exposure in preterm infants with bronchopulmonary dysplasia

OBJECTIVES

Preterm infants and children with bronchopulmonary dysplasia (BPD) often experience significant respiratory morbidities during the first two years of life. Second hand smoke (SHS) has been demonstrated to lead to respiratory morbidities in the general population. The objectives of this study were to assess the prevalence/impact of SHS on preterm infants and children with BPD.

METHODS

Subjects (n = 352) were recruited from the Johns Hopkins BPD outpatient clinic between January 2008 and August 2012. Second hand smoke exposure and respiratory morbidities were assessed through questionnaires and chart review.

RESULTS

Twenty-eight percent of preterm infants with BPD were exposed to SHS in the home setting, despite having significant lung disease. SHS was associated with multiple measures of socio-economic status, including lower household income (P < 0.001), lower caregiver education level (P = 0.013), and having public versus private insurance (P = 0.002). We found no difference in acute care use or chronic symptoms with SHS exposure. We observed trends that preterm infants who were exposed to SHS were more likely to be prescribed inhaled corticosteroids (P = 0.054) and were weaned off of supplemental oxygen over 2 months later (P = 0.13) than infants not exposed to SHS.

CONCLUSION

SHS exposure in preterm infants with BPD is common, even in those receiving supplemental oxygen and respiratory medications. Although there were no associations between respiratory outcomes and self-reported SHS exposure, trends toward increased use of inhaled steroids and a longer duration of supplemental oxygen use were noted. Further work is needed to determine more accurate means of assessing SHS risk in this vulnerable population.

Association of a FGFR-4 gene polymorphism with bronchopulmonary dysplasia and neonatal respiratory distress

Background. Bronchopulmonary dysplasia (BPD) is the most common chronic lung disease of premature birth, characterized by impaired alveolar development and inflammation. Pathomechanisms contributing to BPD are poorly understood. However, it is assumed that genetic factors predispose to BPD and other pulmonary diseases of preterm neonates, such as neonatal respiratory distress syndrome (RDS). For association studies, genes upregulated during alveolarization are major candidates for genetic analysis, for example, matrix metalloproteinases (MMPs) and fibroblast growth factors (FGFs) and their receptors (FGFR). Objective. Determining genetic risk variants in a Caucasian population of premature neonates with BPD and RDS. Methods. We genotyped 27 polymorphisms within 14 candidate genes via restriction fragment length polymorphism (RFLP): MMP-1, -2, -9, and -12, -16, FGF receptors 2 and 4, FGF-2, -3, -4, -7, and -18, Signal-Regulatory Protein α (SIRPA) and Thyroid Transcription Factor-1 (TTF-1). Results. Five single nucleotide polymorphisms (SNPs) in MMP-9, MMP-12, FGFR-4, FGF-3, and FGF-7 are associated (P < 0.05) with RDS, defined as surfactant application within the first 24 hours after birth. One of them, in FGFR-4 (rs1966265), is associated with both RDS (P = 0.003) and BPD (P = 0.023). Conclusion. rs1966265 in FGF receptor 4 is a possible genetic key variant in alveolar diseases of preterm newborns.

Exercise-induced bronchoconstriction in school-aged children who had chronic lung disease in infancy

OBJECTIVES

To assess for exercise-induced bronchoconstriction in 8- to 12-year-old children who had chronic lung disease (CLD) in infancy, and to evaluate the response of bronchoconstriction to bronchodilation with albuterol in comparison with preterm and term controls.

STUDY DESIGN

Ninety-two children, including 29 with CLD, 33 born preterm at ≤32 weeks' gestation, and 30 born at term, underwent lung spirometry before and after cycle ergometry testing and after postexercise bronchodilation with albuterol.

RESULTS

Doctor-diagnosed asthma and exercise-induced wheeze were reported more frequently in the CLD group than in the preterm and term groups, but only 10% were receiving a bronchodilator. There were no differences among the groups in peak minute ventilation, oxygen uptake, or carbon dioxide output at maximum exercise. After maximal exercise, predicted forced expiratory volume in 1 second (FEV1) decreased from a mean baseline value of 81.9% (95% CI, 76.6-87.0%) to 70.8% (95% CI, 65.5-76.1%) after exercise in the CLD group, from 92.0% (95% CI, 87.2-96.8%) to 84.3% (95% CI, 79.1-89.4%) in the preterm group, and from 97.5% (95% CI, 92.5-102.6%) to 90.3% (95% CI, 85.1-95.5%) in the term group. After albuterol administration, FEV1 increased to 86.8% (95% CI, 81.7-92.0%) in the CLD group, 92.1% (95% CI, 87.3-96.9%) in the preterm group, and 97.1% (95% CI, 92.0-102.3%) in the term group. The decrease in predicted FEV1 after exercise and increase in predicted FEV1 after bronchodilator use were greatest in the CLD group (-11.0% [95% CI, -18.4 to -3.6%] and 16.0% [95% CI, 8.6-23.4%], respectively; P < .005 for both), with differences of <8% in the 2 control groups.

CONCLUSION

School-age children who had CLD in infancy had significant exercise-induced bronchoconstriction that responded significantly to bronchodilation. Reversible exercise-induced bronchoconstriction is common in children who experienced CLD in infancy and should be actively assessed for and treated.

Anaesthetic management of the child with co-existing pulmonary disease

Children with co-existing pulmonary disease have a wide range of clinical manifestations with significant implications for anaesthetists. Although there are a number of pulmonary diseases in children, this review focuses on two of the most common pulmonary disorders, asthma and bronchopulmonary dysplasia (BPD). These diseases share the physiology of bronchoconstriction and variably decreased flow in the airways, but also have unique physiological consequences. The anaesthetist can make a difference in outcomes with proper preoperative evaluation and appropriate preparation for surgery in the context of a team approach to perioperative care with implementation of a stepwise approach to disease management. An understanding of the importance of minimizing the risk for bronchoconstriction and having the tools at hand to treat it when necessary is paramount in the care of these patients. Unique challenges exist in the management of pulmonary hypertension in BPD patients. This review covers medical treatment, intraoperative management, and postoperative care for both patient populations.

Nebulised surfactant in preterm infants with or at risk of respiratory distress syndrome

BACKGROUND

Nebulised surfactant has the potential to deliver surfactant to the infant lung with the goal of avoiding endotracheal intubation and ventilation, ventilator-induced lung injury and bronchopulmonary dysplasia (BPD).

OBJECTIVES

To determine the effect of nebulised surfactant administration either as prophylaxis or treatment compared to placebo, no treatment or intratracheal surfactant administration on morbidity and mortality in preterm infants with, or at risk of, respiratory distress syndrome (RDS).

SEARCH METHODS

Searches were performed of CENTRAL (The Cochrane Library, January 2012), MEDLINE and PREMEDLINE (1950 to January 2012), EMBASE (1980 to January 2012) and CINAHL (1982 to January 2012), as well as proceedings of scientific meetings, clinical trial registries, Google Scholar and reference lists of identified studies. Expert informants and surfactant manufacturers were contacted.

SELECTION CRITERIA

Randomised, cluster-randomised or quasi-randomised controlled trials of nebulised surfactant administration compared to placebo, no treatment, or other routes of administration (laryngeal, pharyngeal instillation of surfactant before the first breath, thin endotracheal catheter surfactant administration or intratracheal surfactant instillation) on morbidity and mortality in preterm infants at risk of RDS. We considered published, unpublished and ongoing trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for eligibility and quality, and extracted data.

MAIN RESULTS

No studies of prophylactic or early nebulised surfactant administration were found. A single small study of late rescue nebulised surfactant was included. The study is of moderate risk of bias. The study enrolled 32 preterm infants born < 36 weeks' gestation with RDS on nasal continuous positive airway pressure (nCPAP). The study reported no significant difference between nebulised surfactant administration compared to no treatment groups in chronic lung disease (risk ratio (RR) 5.00; 95% confidence interval (CI) 0.26 to 96.59) or other outcomes (oxygenation 1 to 12 hours after randomisation, need for mechanical ventilation, days of mechanical ventilation or continuous positive airways pressure (CPAP) or days of supplemental oxygen). No side effects of the nebulised surfactant therapy or aerosol inhalation were reported.

AUTHORS' CONCLUSIONS

There are insufficient data to support or refute the use of nebulised surfactant in clinical practice. Adequately powered trials are required to determine the effect of nebulised surfactant administration for prevention or early treatment of RDS in preterm infants. Nebulised surfactant administration should be limited to clinical trials.

Rehospitalization in the first 2 years of life in children born preterm

AIM

Aim of the study is to investigate the frequency of and predictors for rehospitalization within the first 2 years of life among preterm infants.

METHODS

All children born before 32 weeks of gestation in Northern Tyrol between January 2003 and July 2008 were prospectively enrolled. Data on rehospitalizations were obtained from hospital admission records. The association between candidate risk factors and readmission was analysed by means of logistic regression analysis.

RESULTS

In the first and second years of life, 151 and 93 of 377 children (40.1% and 24.7%), respectively, were readmitted to one of the hospitals in Northern Tyrol. The most common causes of rehospitalization were respiratory disorders, accounting for 42.1% and 47.4% of total readmissions in the first and second years of life. Chronic lung disease (CLD), male sex and smoking in pregnancy were risk conditions relevant to readmission in the first year of life, but only CLD in the second year.

CONCLUSION

Infants born before 32 weeks of gestation have a high risk of rehospitalization with respiratory illness significantly contributing to postdischarge morbidity. Neonatal intensive care should aim to further improve respiratory health in preterm infants, and adequate follow-up services must be offered.

Elastase inhibitory activity of airway α1-antitrypsin is protected by treatment with a catalytic antioxidant in a baboon model of severe bronchopulmonary dysplasia

Recent studies in animal models of bronchopulmonary dysplasia (BPD) suggest that antioxidant treatments may be beneficial for the disease. However, the mechanisms by which these drugs improve the course of BPD are not completely known. Alpha1-antitrypsin (α1-AT) is one of the major serine protease inhibitors in human plasma that has antielastase and antiapoptotic activities. Both activities of α1-AT are dependent on its reactive site loop (RSL), which is highly susceptible to oxidative inactivation. In this study, we investigated the elastase inhibitory activity of α1-AT in two different baboon models of BPD, the "new BPD" and the "severe BPD" models, and determined the effect of treatment with a catalytic antioxidant, Mn(III) meso-tetrakis(N-ethylpyridinium-2-yl)porphyrin (MnTE-2-PyP), on the elastase inhibitory activity of α1-AT in the severe BPD model. Our results demonstrate the presence of sufficient elastase inhibitory activity of the airway α1-AT in the new but not in the severe BPD model. Treatment of severe BPD group baboons with the catalytic antioxidant MnTE-2-PyP resulted in augmentation of the elastase inhibitory activity of α1-AT. These findings suggest that prevention of the oxidative inactivation of α1-AT may be one of the mechanisms by which antioxidant therapy improves the pulmonary outcomes in animal models of severe BPD.

Laryngeal mask airway surfactant administration for prevention of morbidity and mortality in preterm infants with or at risk of respiratory distress syndrome

BACKGROUND

Laryngeal mask airway (LMA) administration is one way of delivering surfactant to the infant lung, with the potential benefit of avoiding endotracheal intubation and ventilation, ventilator induced lung injury and bronchopulmonary dysplasia (BPD).

OBJECTIVES

To determine the effect of LMA surfactant administration either as prophylaxis or treatment compared to placebo, no treatment, or intratracheal surfactant administration on morbidity and mortality in preterm infants with, or at risk of, respiratory distress syndrome (RDS).

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library, October 2010), MEDLINE and PREMEDLINE (1950 to October 2010), EMBASE (1980 to October 2010) and CINAHL (1982 to October 2010). We also searched proceedings of scientific meetings, clinical trial registries, Google Scholar and reference lists of identified studies, as well as contacting expert informants and surfactant manufacturers.

SELECTION CRITERIA

Randomised, cluster-randomised or quasi-randomised controlled trials of laryngeal mask surfactant administration compared to placebo, no treatment, or other routes of administration (nebulised, pharyngeal instillation of surfactant before the first breath, thin endotracheal catheter surfactant administration or intratracheal surfactant instillation) on morbidity and mortality in preterm infants at risk of RDS. We considered published, unpublished and ongoing trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for eligibility and quality, and extracted data.

MAIN RESULTS

We found no studies of prophylactic or early LMA surfactant administration. A single small study of late rescue LMA surfactant was identified as eligible for inclusion. The study enrolled 26 preterm infants born ≥ 1200 g with RDS on continuous positive airway pressure (nCPAP). LMA surfactant administration compared to no treatment resulted in a reduction in mean FiO(2) required to maintain oxygen saturation between 88% and 92% for 12 hours after the intervention. No significant difference was reported in subsequent mechanical ventilation and endotracheal surfactant, pneumothorax, days on intermittent positive airway pressure (IPPV), and days on IPPV or oxygen.

AUTHORS' CONCLUSIONS

There is evidence from a single small trial that LMA surfactant administration in preterm infants ≥ 1200 g with established RDS may have a short term effect in reducing oxygen requirements although the study is underpowered to detect important clinical effects. Adequately powered trials are required to determine the effect of LMA surfactant administration for prevention or treatment of RDS in preterm infants. LMA surfactant administration should be limited to clinical trials.

Intratracheal Clara cell secretory protein (CCSP) administration in preterm infants with or at risk of respiratory distress syndrome

BACKGROUND

Clara cell secretary protein (CCSP) is an immune-modulating and anti-inflammatory agent. CCSP is available synthetically as recombinant human Clara cell protein (rhCC10). It has been shown in animal models to reduce lung injury, improve pulmonary compliance and oxygenation, decrease systemic inflammation and up-regulate surfactant protein and vascular endothelial growth factor expression. These properties makes intratracheally administered CCSP a potential agent in prevention of chronic lung disease (CLD).

OBJECTIVES

To determine the effect of intratracheal CCSP administration compared to placebo or no treatment on morbidity and mortality in preterm infants with or at risk of respiratory distress syndrome (RDS).

SEARCH STRATEGY

We searched CENTRAL (The Cochrane Library, October 2010), MEDLINE and PREMEDLINE (1950 to October 2010), EMBASE (1980 to October 2010) and CINAHL (1982 to October 2010). We searched proceedings of scientific meetings, Google Scholar and reference lists of identified studies, and contacted expert informants and surfactant manufacturers.

SELECTION CRITERIA

Published, unpublished and ongoing randomised controlled, cluster-randomised or quasi-randomised trials of intratracheal CCSP administration, compared to placebo or no treatment on morbidity and mortality in preterm infants at risk of RDS.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for eligibility and quality, and extracted data.

MAIN RESULTS

One pilot study was identified and included. This study enrolled 22 preterm infants 700 to 1300g with established RDS who required ventilation for surfactant administration. Infants received one intratracheal dose of placebo (n = 7), 1.5 mg/kg (n = 8) or 5 mg/kg (n = 7) rhCC10 within four hours of surfactant treatment. At either dose of rhCC10, no significant difference was reported in CLD (36 weeks postmenstrual age or 28 days), mortality, intraventricular haemorrhage, periventricular leukomalacia, patent ductus arteriosus, necrotising enterocolitis, sepsis or days supplemental oxygen compared to placebo. A significant increase in days mechanical ventilation was reported for infants receiving rhCC10 5mg/kg (mean difference 12.00, 95% confidence interval 0.39 to 23.61) but not at the lower dose. The study reported that a single intratracheal dose of rhCC10 was well tolerated and resulted in a significant reduction in tracheal aspirate neutrophil and total cell count, and lung protein concentration. There was no significant difference reported in tracheal aspirate cytokine levels between groups.

AUTHORS' CONCLUSIONS

There are insufficient data to determine the role of rhCC10 in clinical practice. Further studies are required to determine if rhCC10 reduces lung inflammation in infants at risk of CLD, and to determine dose and dosing strategy.

Pharyngeal instillation of surfactant before the first breath for prevention of morbidity and mortality in preterm infants at risk of respiratory distress syndrome

BACKGROUND

Intrapartum pharyngeal instillation of surfactant before the first breath may result in surfactant administration to the infant lung, with the potential benefit of avoiding endotracheal intubation and ventilation, ventilator induced lung injury and bronchopulmonary dysplasia.

OBJECTIVES

To determine the effect of pharyngeal instillation of surfactant before the first breath compared to placebo, no treatment or intratracheal surfactant administration followed by intermittent positive pressure ventilation (IPPV) on morbidity and mortality in preterm infants at risk of respiratory distress syndrome (RDS).

SEARCH STRATEGY

Searches were made of CENTRAL (The Cochrane Library, to September 2010), MEDLINE and PREMEDLINE (1950 to September 2010), EMBASE (1980 to 2010) and CINAHL (1982 to 2010). This strategy was supplemented by searches of proceedings of scientific meetings, Google Scholar and reference lists of identified studies, as well as contact with expert informants and surfactant manufacturers.

SELECTION CRITERIA

Published, unpublished and ongoing randomised controlled or quasi-randomised trials (using individual or cluster allocation) of pharyngeal instillation of surfactant before the first breath compared to placebo or no treatment, or intratracheal surfactant instillation followed by IPPV, on morbidity and mortality in preterm infants at risk of RDS.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility and quality.

MAIN RESULTS

No published, unpublished or ongoing trials that met the inclusion criteria for this review were found.

AUTHORS' CONCLUSIONS

There were no data from randomised controlled or quasi-randomised trials that evaluated the effect of intrapartum instillation of pharyngeal surfactant before the first breath. Evidence from animal and observational human studies suggest that pharyngeal instillation of surfactant before the first breath is potentially safe, feasible and may be effective. Well designed trials are needed.

Environmental Modifiers of Chronic Lung Disease of Prematurity During Infancy

Chronic lung disease is a common complication of prematurity with substantial mortality and morbidity. Although the variation seen in bronchopulmonary dysplasia has a strong genetic component, the limited environmental variation in neonatal intensive care units may lead to underestimates of the contribution of environmental factors to lung disease variation. Once discharged from the hospital, preterm infants are exposed to a variety of environmental factors that likely worsen their disease. Recognition of these factors may lead to improved outcomes in this vulnerable population through more effective guidelines and counseling. This review examines the role of selected outpatient environmental factors on respiratory outcomes during infancy in preterm infants with lung disease.

The use of culture-independent tools to characterize bacteria in endo-tracheal aspirates from pre-term infants at risk of bronchopulmonary dysplasia

Although premature infants are increasingly surviving the neonatal period, up to one-third develop bronchopulmonary dysplasia (BPD). Despite evidence that bacterial colonization of the neonatal respiratory tract by certain bacteria may be a risk factor in BPD development, little is known about the role these bacteria play. The aim of this study was to investigate the use of culture-independent molecular profiling methodologies to identify potential etiological agents in neonatal airway secretions. This study used terminal restriction fragment length polymorphism (T-RFLP) and clone sequence analyses to characterize bacterial species in endo-tracheal (ET) aspirates from eight intubated pre-term infants. A wide range of different bacteria was identified in the samples. Forty-seven T-RF band lengths were resolved in the sample set, with a range of 0-15 separate species in each patient. Clone sequence analyses confirmed the identity of individual species detected by T-RFLP. We speculate that the identification of known opportunistic pathogens including S. aureus, Enterobacter sp., Moraxella catarrhalis, Pseudomonas aeruginosa and Streptococcus sp., within the airways of pre-term infants, might be causally related to the subsequent development of BPD. Further, we suggest that culture-independent techniques, such as T-RFLP, hold important potential for the characterization of neonatal conditions, such as BPD.

Severity of bronchopulmonary dysplasia and increased risk of feeding desaturation and growth delay in very low birth weight preterm infants

Oral feeding has been reported to compromise breathing among preterm infants with bronchopulmonary dysplasia (BPD) during hospitalization or shortly after discharge. However, limited information was available concerning whether preterm infants with BPD remain vulnerable to feeding and growth insufficiency after a longer term of follow-up. The purpose of this study was therefore to examine the effect of severity of BPD on pulse oxygen saturation (SpO(2)) during feeding and growth in very low birth weight (VLBW) preterm infants during infancy. Seventy-two preterm infants with VLBW and 15 term infants were prospectively examined their growth and SpO(2) during feeding at 2, 4, and 6 months of corrected age. The severity of BPD was graded in VLBW infants according to the American National Institutes of Health consensus definition. In comparison to VLBW infants with mild BPD and term infants, VLBW infants with severe BPD showed significantly lower mean levels of SpO(2) during feeding at 2-6 months corrected age (P < 0.05). Those with severe BPD further exhibited higher rates of growth delay (weight < 10th percentile) throughout the study period. Among VLBW infants, severe BPD had an adverse relation with subsequent weight measures after adjustment for medical and demographic confounding variables (beta = -904 g, P = 0.03). The consensus BPD definition is useful to identify those preterm infants who are at greater risk of feeding desaturation and growth delay during infancy and close monitoring of SpO(2) during feeding should be advised.

Intra-amniotic surfactant for women at risk of preterm birth for preventing respiratory distress in newborns

BACKGROUND

Early surfactant reduces mortality and pulmonary complications in preterm infants with respiratory distress syndrome. However, current surfactant administration strategies require endotracheal intubation with or without continued mechanical ventilation. Bronchopulmonary dysplasia and chronic lung disease (CLD) are associated with mechanical ventilation and potentially life-long effects. Non-invasive methods of surfactant administration including intra-amniotic surfactant may avoid endotracheal intubation and mechanical ventilation, potentially preventing development of CLD.

OBJECTIVES

To determine if intra-amniotic instillation of surfactant for women at risk of preterm birth, compared to placebo or no treatment or post-delivery tracheal surfactant instillation, reduces morbidity or mortality, or both, in preterm infants. If intra-amniotic instillation is effective, in subgroup analysis to determine the effect of 1) gestational age; 2) type of surfactant; 3) dose; 4) timing; 5) indication; and 6) multiple pregnancy.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (August 2009), MEDLINE (1950-August 2009), handsearched the Proceedings of Pediatric Academic Societies (American Pediatric Society, Society for Pediatric Research and European Society for Pediatric Research) from 1990-2009 in Pediatric Research Journal and Abstracts online and the Proceedings of Perinatal Society of Australia and New Zealand (PSANZ) (1996-2009). We also searched the Science Citation Index (Web of Science) (August 2009) and checked reference lists of identified studies. We contacted Abbott Laboratories, Inc for unpublished studies.

SELECTION CRITERIA

Published, unpublished and ongoing randomised controlled, cluster-randomised or quasi-randomised trials of intra-amniotic instillation of surfactant for women at risk of preterm birth, compared to placebo or no treatment or post-delivery tracheal surfactant instillation.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed study eligibility and quality.

MAIN RESULTS

We found no trials were found met the inclusion criteria for this review.

AUTHORS' CONCLUSIONS

We identified no randomised trials that evaluated the effect of intra-amniotic instillation of surfactant for women at risk of preterm birth. Evidence from animal and observational human studies suggest that intra-amniotic surfactant administration is potentially safe, feasible and effective. Well designed trials of intra-amniotic instillation of surfactant for women at risk of preterm birth are needed.

A pumpless lung assist device reduces mechanical ventilation-induced lung injury in juvenile piglets

Respiratory failure is a major contributor to mortality and morbidity in newborn infants. The lung assist device (LAD) is a novel gas exchange device that supplements mechanical ventilation. The objective is to test the effect of the LAD on pulmonary histopathology in juvenile piglets with acute lung injury caused by saline lung lavage (SLL) followed by intermittent mandatory ventilation (IMV). Three- to 4-wk-old piglets were randomized to no intervention (control group), SLL alone (SLL group), SLL + IMV (IMV group), or SLL + IMV + LAD (LAD group) (n = 6 per group). The carotid artery and jugular vein were cannulated and an arteriovenous circuit completed, and the LAD was inserted into this circuit. Gas exchange via the LAD was initiated by passage of 100% oxygen over the blood-carrying hollow fibers of the LAD. Hemodynamic variables were recorded. Mechanical ventilation was systematically weaned. Lung histology was scored by two observers masked to treatment group. There were no differences in hemodynamic variables between the study groups. There was a significant increase in the total lung injury score in the IMV group compared with the LAD group. The novel pumpless low-resistance LAD has shown feasibility and potential to decrease ventilator-induced lung injury in a juvenile animal model.

Long-term outcomes of bronchopulmonary dysplasia

As more very preterm infants survive, more survivors will have bronchopulmonary dysplasia (BPD). Children with BPD have higher rates of cognitive, educational and behavioural impairments, and also reduced lung function, through childhood and into early life than would normally be expected. The importance of these neurological and respiratory problems later into adult life needs to be determined.

Hyperoxia-induced neonatal rat lung injury involves activation of TGF-{beta} and Wnt signaling and is protected by rosiglitazone

Despite tremendous technological and therapeutic advances, bronchopulmonary dysplasia (BPD) remains a leading cause of respiratory morbidity in very low birth weight infants, and there are no effective preventive and/or therapeutic options. We have previously reported that hyperoxia-induced neonatal rat lung injury might be prevented by rosiglitazone (RGZ). Here, we characterize 1) perturbations in wingless/Int (Wnt) and transforming growth factor (TGF)-beta signaling, and 2) structural aberrations in lung morphology following 7-day continuous in vivo hyperoxia exposure to neonatal rats. We also tested whether treatment of neonatal pups with RGZ, concomitant to hyperoxia, could prevent such aberrations. Our study revealed that hyperoxia caused significant upregulation of Wnt signaling protein markers lymphoid enhancer factor 1 (Lef-1) and beta-catenin and TGF-beta pathway transducers phosphorylated Smad3 and Smad7 proteins in whole rat lung extracts. These changes were also accompanied by upregulation of myogenic marker proteins alpha-smooth muscle actin (alpha-SMA) and calponin but significant downregulation of the lipogenic marker peroxisome proliferator-activated receptor-gamma (PPARgamma) expression. These molecular perturbations were associated with reduction in alveolar septal thickness, radial alveolar count, and larger alveoli in the hyperoxia-exposed lung. These hyperoxia-induced molecular and morphological changes were prevented by systemic administration of RGZ, with lung sections appearing near normal. This is the first evidence that in vivo hyperoxia induces activation of both Wnt and TGF-beta signal transduction pathways in lung and of its near complete prevention by RGZ. Hyperoxia-induced arrest in alveolar development, a hallmark of BPD, along with these molecular changes strongly implicates these proteins in hyperoxia-induced lung injury. Administration of PPARgamma agonists may thus be a potential strategy to attenuate hyperoxia-induced lung injury and subsequent BPD.

The long-term follow-up of patients with a congenital diaphragmatic hernia: a broad spectrum of morbidity

Congenital diaphragmatic hernia (CDH) is a life-threatening anomaly with a mortality rate of approximately 40-50%, depending on case selection. It has been suggested that new therapeutic modalities such as nitric oxide (NO), high frequency oxygenation (HFO) and extracorporal membrane oxygenation (ECMO) might decrease mortality associated with pulmonary hypertension and the sequelae of artificial ventilation. When these new therapies indeed prove to be beneficial, a larger number of children with severe forms of CDH might survive, resulting in an increase of CDH-associated complications and/or consequences. In follow-up studies of infants born with CDH, many complications including pulmonary damage, cardiovascular disease, gastro-intestinal disease, failure to thrive, neurocognitive defects and musculoskeletal abnormalities have been described. Long-term pulmonary morbidity in CDH consists of obstructive and restrictive lung function impairments due to altered lung structure and prolonged ventilatory support. CDH has also been associated with persistent pulmonary vascular abnormalities, resulting in pulmonary hypertension in the neonatal period. Long-term consequences of pulmonary hypertension are unknown. Gastro-esophageal reflux disease (GERD) is also an important contributor to overall morbidity, although the underlying mechanism has not been fully understood yet. In adult CDH survivors incidence of esophagitis is high and even Barrett's esophagus may ensue. Yet, in many CDH patients a clinical history compatible with GERD seems to be lacking, which may result in missing patients with pathologic reflux disease. Prolonged unrecognized GERD may eventually result in failure to thrive. This has been found in many young CDH patients, which may also be caused by insufficient intake due to oral aversion and increased caloric requirements due to pulmonary morbidity. Neurological outcome is determined by an increased risk of perinatal and neonatal hypoxemia in the first days of life of CDH patients. In patients treated with ECMO, the incidence of neurological deficits is even higher, probably reflecting more severe hypoxemia and the risk of ECMO associated complications. Many studies have addressed the substantial impact of the health problems described above, on the overall well-being of CDH patients, but most of them concentrate on the first years after repair and only a few studies focus on the health-related quality of life in CDH patients. Considering the scattered data indicating substantial morbidity in long-term survivors of CDH, follow-up studies that systematically assess long-term sequelae are mandatory. Based on such studies a more focused approach for routine follow-up programs may be established.

One-year respiratory outcomes of preterm infants enrolled in the Nitric Oxide (to prevent) Chronic Lung Disease trial

OBJECTIVE

To identify whether inhaled nitric oxide treatment decreased indicators of long-term pulmonary morbidities after discharge from the neonatal intensive care unit.

STUDY DESIGN

The Nitric Oxide (to Prevent) Chronic Lung Disease trial enrolled preterm infants (<1250 g) between 7 to 21 days of age who were ventilated and at high risk for bronchopulmonary dysplasia. Follow-up occurred at 12 +/- 3 months of age adjusted for prematurity; long-term pulmonary morbidity and other outcomes were reported by parents during structured blinded interviews.

RESULTS

A total of 456 infants (85%) were seen at 1 year. Compared with control infants, infants randomized to inhaled nitric oxide received significantly less bronchodilators (odds ratio [OR] 0.53 [95% confidence interval 0.36-0.78]), inhaled steroids (OR 0.50 [0.32-0.77]), systemic steroids (OR 0.56 [0.32-0.97]), diuretics (OR 0.54 [0.34-0.85]), and supplemental oxygen (OR 0.65 [0.44-0.95]) after discharge from the neonatal intensive care unit. There were no significant differences between parental report of rehospitalizations (OR 0.83 [0.57-1.21]) or wheezing or whistling in the chest (OR 0.70 [0.48-1.03]).

CONCLUSIONS

Infants treated with inhaled nitric oxide received fewer outpatient respiratory medications than the control group. However, any decision to institute routine use of this dosing regimen should also take into account the results of the 24-month neurodevelopmental assessment.

Cardiopulmonary outcomes of extreme prematurity

Cardiopulmonary diseases dominate the early days after birth for very preterm babies, but most survive these disorders. However, a minority who survive remain oxygen-dependent for a prolonged period, including after discharge. For the remaining very preterm survivors, cardiopulmonary problems are not major health issues in early childhood, apart from higher rates of hospital readmission for respiratory illnesses in the first few years after the primary hospitalization. However, as they progress through childhood and into adulthood, it is clear that very preterm survivors have reduced lung function, higher blood pressure, and other cardiovascular abnormalities that may lead to adverse cardiopulmonary outcomes much earlier in adult life than would normally be expected. The contribution of these cardiopulmonary problems in early adulthood to morbidity in middle and old ages needs to be determined.

Behaviour and quality of life at school age of children who had bronchopulmonary dysplasia

BACKGROUND

There is little information available concerning behavioural and functional health problems in children who had bronchopulmonary dysplasia (BPD).

AIM

To compare behavioural problems and quality of life in a cohort of children at school age who had BPD with preterm and term controls.

METHODS

The cohort of 78 BPD children of 26 to 33 weeks' gestation was matched for birth weight with preterm controls. At school age follow-up, information was available for 66 BPD children and 60 preterm controls. (Three children with severe cerebral palsy were excluded). Parents completed the Child Behaviour Checklist (CBCL) and the Child Health Questionnaire (CHQ). The child's teacher completed the Teacher Report Form (TRF) of the CBCL, with the teachers of the BPD children completing a TRF on a classroom control. Parents completed a questionnaire on their levels of anxiety and depression.

RESULTS

The mean total problem score on the CBCL for the BPD children was similar to the controls, with the BPD children displaying more internalising behaviours. Little variation was seen between the BPD and preterm children on the TRF. Significant differences between classroom controls and the BPD children were found for the total problem scores (p=0.001), internalising behaviours (p=0.01) and social (p=0.047), attention (p=0.0001) and thought problems (0.047). Results from the CHQ showed no difference between the groups in their physical health or the impact of health problems on family life.

CONCLUSION

BPD children at school age display more internalising behaviour than preterm controls, with marked differences on comparison with classroom controls. Quality of life, however, does not seem to be adversely affected compared to the preterm controls.

Is there evidence that long-term outcomes have improved with intensive care?

Advances in perinatal interventions over the past three decades, such as antenatal steroid therapy, ventilator techniques, surfactant therapy, and enhanced nutrition have resulted in a dramatic improvement in the survival of very low birth weight (VLBW) infants. Simultaneously, other advances in reproductive technology procedures have resulted in greater numbers of preterm and multiple births. These extremely premature births account for the vast majority of infant mortality and morbidity in the developed world. Despite the innovative interventions, VLBW infants remain at substantial risk for a wide spectrum of long-term morbidity including cerebral palsy (CP), mental retardation, developmental delay, school problems, behavioral issues, growth failure, and overall poor health status. Recently, ethical concerns have been expressed that improved survival rates for the most immature infants may result in increased rates of disability with substantial resource utilization and declining quality of life for the survivors. This chapter critically evaluates the available neurodevelopmental and health outcomes of very premature infants from the developed world in an attempt to determine if there is evidence that long-term outcomes have improved with neonatal intensive care. Studies on the rates of neurodevelopmental impairment including CP, early childhood and school age functional problems, and special health care issues are surveyed in order to evaluate changes over time and provide an assessment of the success of neonatal intensive care over the past three decades.

Chronic lung disease of prematurity and respiratory outcome at eight years of age

AIM

The study aimed to determine the respiratory outcome of children who had chronic lung disease of prematurity (CLD) compared with a preterm control group of children at school age.

METHODS

Fifty-two preterm infants with CLD born between 26 and 33 weeks gestation were assessed regarding respiratory illness with 47 having lung function testing. Information regarding respiratory illness was obtained from 52 children in the birthweight-matched control group of whom 45 had lung function testing. The results were compared between the CLD and control groups.

RESULTS

There was no difference in respiratory symptomatology between CLD groups and control preterm infants. On lung function testing, a significantly lower mean forced expiratory flow at 25-75% of vital capacity was identified compared with the preterm controls (P=0.024). This significant difference did not persist after bronchodilator therapy. There was no evidence of increased air trapping or bronchial hyper-reactivity in the CLD children compared with the controls.

CONCLUSION

Lung function in CLD children is largely normal in comparison with preterm controls, apart from some evidence of reversible small airway obstruction. Respiratory symptomatology is not increased in chronic disease children in comparison with control preterm children.

Prevention of bronchopulmonary dysplasia: finally, something that works

Due to a lack of understanding of the molecular mechanisms involved in its pathogenesis, bronchopulmonary dysplasia (BPD) still remains a major cause of morbidity and mortality in the premature infant and there is no effective preventive and/or therapeutic intervention. We have taken a basic biologic approach to elucidate the pathophysiology of BPD and have discovered that disruption of the alveolar Parathyroid Hormone-related Protein (PTHrP) signaling is centrally involved in this process. Further, stabilization of this signaling pathway by using exogenous PTHrP agonists can prevent and/or rescue the molecular injuries caused by insults that lead to BPD. Based upon years of work in this field, here I provide a novel and innovative molecular approach, i.e, exogenous treatment with PTHrP pathway agonists to prevent and/or treat BPD. However, to avoid any later surprises, it is important to emphasize that before translating it into human trials, this approach needs further testing and refinement in animal models.

Pulmonary outcomes in bronchopulmonary dysplasia

The incidence of bronchopulmonary dysplasia (BPD), defined as oxygen need at 36 weeks of postmenstrual age, is about 30% for infants with birth weights <1000 g. BPD is associated with persistent structural changes in the lung that result in significant effects on lung mechanics, gas exchange, and pulmonary vasculature. Up to 50% of infants with BPD require readmission to the hospital for lower respiratory tract illness in the first year of life. Long-term measurements of lung function in BPD include normalization of pulmonary mechanics and some lung volumes over time as somatic and lung growth occur, whereas abnormality of small airway function persists. The majority of data reveals no long-term decrease in exercise capacity. Mild to moderate radiological abnormalities persist. BPD is a result of dynamic processes involving inflammation, injury, repair, and maturation. Infants with BPD have significant pulmonary sequelae during childhood and adolescence, and continued surveillance of young adults with BPD is critical.

Prenatal predictors of chronic lung disease in very preterm infants

OBJECTIVE

To identify prenatal risk factors for chronic lung disease (CLD) at 36 weeks postmenstrual age in very preterm infants.

POPULATION

Data were collected prospectively as part of the ongoing audit of the Australian and New Zealand Neonatal Network (ANZNN) of all infants born at less than 32 weeks gestation admitted to all tertiary neonatal intensive care units in Australia and New Zealand.

METHODS

Prenatal factors up to 1 minute of age were examined in the subset of infants born at gestational ages 22-31 weeks during 1998-2001, and who survived to 36 weeks postmenstrual age (n = 11 453). Factors that were significantly associated with CLD at 36 weeks were entered into a multivariate logistic regression model.

RESULTS

After adjustment, low gestational age was the dominant risk factor, with an approximate doubling of the odds with each week of decreasing gestational age from 31 to less than 25 weeks (trend p<0.0001). Birth weight for gestational age also had a dose-response effect: the lower the birth weight for gestational age, the greater the risk, with infants below the third centile having 5.67 times greater odds of CLD than those between the 25th and 75th centile (trend p<0.0001). There was also a significantly increased risk for male infants (odds ratio 1.51 (95% confidence interval 1.36 to 1.68), p<0.0001).

CONCLUSIONS

These population based data show that the prenatal factors low gestational age, low birth weight for gestational age, and male sex significantly predict the development of chronic respiratory insufficiency in very preterm infants and may assist clinical decision about delivery.

Gender differences in respiratory symptoms in 19-year-old adults born preterm

Objective

To study the prevalence of respiratory and atopic symptoms in (young) adults born prematurely, differences between those who did and did not develop Bronchopulmonary Disease (BPD) at neonatal age and differences in respiratory health between males and females.

Methods

Design: Prospective cohort study.

Setting: Nation wide follow-up study, the Netherlands.

Participants: 690 adults (19 year old) born with a gestational age below 32 completed weeks and/or with a birth weight less than 1500 g. Controls were Dutch participants of the European Community Respiratory Health Survey (ECRHS).

Main outcome measures: Presence of wheeze, shortness of breath, asthma, hay fever and eczema using the ECRHS-questionnaire

Results

The prevalence of doctor-diagnosed asthma was significantly higher in the ex-preterms than in the general population, whereas eczema and hay fever were significant lower. Women reported more symptoms than men. Preterm women vs controls: asthma 13% vs 5% (p < 0.001); hay fever 8% vs 20% (p < 0.001); eczema 10% vs 42% (p < 0.001). Preterm men vs controls: asthma 9% vs 4% (p = 0.007); hay fever 8% vs 17% (p = 0.005); eczema 9% vs 31% (p < 0.001) Preterm women reported more wheeze and shortness of breath during exercise (sob) than controls: wheeze 30% vs 22% (p = 0.009); sob 27% vs 16% (p < 0.001); 19-year-old women with BPD reported a higher prevalence of doctor diagnosed asthma compared to controls (24% vs 5% p < 0.001) and shortness of breath during exercise (43% vs 16% p = 0.008). The prevalence of reported symptoms by men with BPD were comparable with the controls.

Conclusion

Our large follow-up study shows a higher prevalence of asthma, wheeze and shortness of breath in the prematurely born young adults. 19-year-old women reported more respiratory symptoms than men. Compared to the general population atopic diseases as hay fever and eczema were reported less often.

Réhospitalisation dans l'année suivant leur naissance des prématurés d'âge gestationnel inférieur ou égal à 32 semaines d'aménorrhée. Comparaison de 2 cohortes : 1997 et 2002

OBJECTIVE

The aim of the study was to compare the rehospitalization rate in the first year of life between 2 groups of very preterm infants born on 1997 and 2002; then we compared the very preterm infants' rehospitalization rate between our retrospective 1997 group and literature (including French cohort Epipage).

PATIENTS AND METHODS

Our retrospective study included all neonates born<or=33 GA, living in Gironde, discharged from neonatal unit at children's hospital of Bordeaux on 1997 and 2002 and rehospitalized during their first year of life.

RESULTS

Respectively 29.1% and 30.1% premature infants were rehospitalized (at least once) in 1997 and 2002 (38.2% in Epipage cohort, no statistical difference). Mean number of rehospitalizations was 1.66 in 1997 and 1.77 in 2002. Mean duration of rehospitalization was 11.8 days in 1997 and 16.8 days in 2002. These data showed no statistical difference between 1997 and 2002. Respiratory disease was the first reason of rehospitalization. Several factors were correlated with an increase risk of rehospitalization: birth weight less than 1000 g, chronic lung disease and gestational age less than 28 weeks at birth (only in 2002 cohort).

CONCLUSION

Rehospitalization rate remained stable between 1997 and 2002 whereas during this period of time, the gravity of these preterm infants had increased. The use of specific hospital discharge procedure represents a real benefit for premature infants. It must be continued after the discharge with the establishment of a strong network with the implication of parents, infants, hospital and city health workers. It may contribute to limit the very premature babies' rehospitalization rate.

Some chronic obstructive pulmonary disease will originate in neonatal intensive care units

Chronic lung disease is the most common adverse outcome in survivors of prematurity. These infants experience frequent hospitalisation because of respiratory-related illness in their first year, as well as persistent cough, wheeze and oxygen dependence. Although the severity of respiratory illness decreases and supplemental oxygen is needed less as their lungs mature, childhood is still complicated by persistent wheeze, cough and reduced exercise tolerance in comparison with their peers. Although there is little longitudinal follow-up data beyond adolescence, imaging studies suggest that these infants are highly likely to suffer with respiratory problems akin to chronic obstructive pulmonary disease in later adulthood. The nature of their long-term respiratory problems, the impact of cigarette smoking and the effect on life expectancy are all unanswered questions that need addressing as these infants grow up.