Inhaled bronchodilator exposure in the management of bronchopulmonary dysplasia in hospitalized infants

Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is a chronic lung disease, associated with premature birth, that arises during the infantile period. It is an evolving disease process with an unchanged incidence due to advancements in neonatal care which allow for the survival of premature infants of lower gestational ages and birth weights. Currently, there are few effective interventions to prevent BPD. However, careful attention to BPD phenotypes and comprehensive care provided by an interdisciplinary team have improved care. Interventions early in the disease course hold promise for improving long-term survival and outcomes in adulthood for this high-risk population.

Advances in the pharmacological management of bronchopulmonary dysplasia: an update of the literature

INTRODUCTION

Bronchopulmonary dysplasia (BPD) is the commonest adverse outcome of extremely prematurely born infants, and its incidence is increasing. Affected infants suffer chronic respiratory morbidity and are at risk of early onset of chronic obstructive pulmonary disease. It is, therefore, important that these infants are appropriately managed, with efficacious pharmacological treatments.

AREAS COVERED

Searches were made on Embase, PubMed, and the Cochrane database for ('treatment' or 'drug therapy/') and ('bronchopulmonary dysplasia' or 'chronic lung disease') and ('neonatology' or 'newborn' or 'prematurity' or 'baby') between 2019 and 2024. Corticosteroids, diuretics, caffeine, anti-asthmatics, nutritional supplements, and medications treating patent ductus arteriosus and pulmonary hypertension are discussed.

EXPERT OPINION

Dexamethasone is associated with adverse neurodevelopmental outcomes and impairment of adult lung function. Inhaled corticosteroids have not resulted in significant effects on BPD. Diuretics only result in short-term improvements in lung function and have side-effects. Evidence suggests it is better to wait and see than aggressively treat PDA; inhaled nitric oxide and sildenafil can improve oxygenation, but whether they improve long-term outcomes remains to be tested. Stem cells are a promising therapy, but further research is required. Appropriately designed trials are required to identify efficacious treatments for infants with BPD.

Recent progress in neonatal hyperoxic lung injury

With the progress in neonatal intensive care, there has been an increase in the survival rates of premature infants. However, this has also led to an increased incidence of neonatal hyperoxia lung injury and bronchopulmonary dysplasia (BPD), whose pathogenesis is believed to be influenced by various prenatal and postnatal factors, although the exact mechanisms remain unclear. Recent studies suggest that multiple mechanisms might be involved in neonatal hyperoxic lung injury and BPD, with sex also possibly playing an important role, and numerous drugs have been proposed and shown promise for improving the treatment outcomes of hyperoxic lung injury. Therefore, this paper aims to analyze and summarize sex differences in neonatal hyperoxic lung injury, potential pathogenesis and treatment progress to provide new ideas for basic and clinical research in this field.

Inhaled Corticosteroid Exposure in Hospitalized Infants with Bronchopulmonary Dysplasia

OBJECTIVE

The objective of this paper was to determine inhaled corticosteroid (IC) use in infants with bronchopulmonary dysplasia (BPD), define the interhospital variation of IC administration to infants with BPD, and compare clinical, demographic, and hospital factors associated with IC use.

STUDY DESIGN

Using the Pediatric Health Information System database, a retrospective multicenter cohort of 4,551 infants born at <32 weeks of gestation with developing BPD was studied. The clinical, demographic, and hospital characteristics of infants exposed and not exposed to ICs were compared.

RESULTS

IC use varied markedly between hospitals, ranging from 0 to 66% of infants with BPD exposed to ICs. Increased annual BPD census was not associated with IC use. In total, 25% (1,144 out of 4,551) of patients with BPD and 43% (536 out of 1,244) of those with severe BPD received ICs. Increased IC exposure was associated with lower birth weight and gestational age, days on respiratory support, need for positive pressure ventilation at 36-week postmenstrual age, need for tracheostomy, and increased use of systemic steroids, bronchodilators, and diuretics.

CONCLUSION

IC exposure is common in infants with BPD, with substantial interhospital variability. IC use was associated with more severe disease. Hospital experience did not account for the wide variability in IC use by the hospital. Further research into the effects of ICs use is urgently needed to help guide their use in this vulnerable population.

KEY POINTS

· The risks and benefits of IC use in infants with BPD are incompletely understood.. · IC use is common in infants with BPD (25%) and severe BPD (43%) varies widely by hospital (0-66% of patients with BPD received an IC).. · Hospital experience did not account for the wide interhospital variation in IC use..

Inhaled bronchodilators for the prevention and treatment of chronic lung disease in preterm infants

BACKGROUND

Chronic lung disease (CLD) occurs frequently in preterm infants and is associated with respiratory morbidity. Bronchodilators have the potential effect of dilating small airways with muscle hypertrophy. Increased compliance and tidal volume, and decreased airway resistance, have been documented with the use of bronchodilators in infants with CLD. Therefore, bronchodilators are widely considered to have a role in the prevention and treatment of CLD, but there remains uncertainty as to whether they improve clinical outcomes. This is an update of the 2016 Cochrane review.

OBJECTIVES

To determine the effect of inhaled bronchodilators given as prophylaxis or as treatment for chronic lung disease (CLD) on mortality and other complications of preterm birth in infants at risk for or identified as having CLD.

SEARCH METHODS

An Information Specialist searched CENTRAL, MEDLINE, Embase, CINAHL and three trials registers from 2016 to May 2023. In addition, the review authors undertook reference checking, citation searching and contact with trial authors to identify additional studies.

SELECTION CRITERIA

We included randomised and quasi-randomised controlled trials involving preterm infants less than 32 weeks old that compared bronchodilators to no intervention or placebo. CLD was defined as oxygen dependency at 28 days of life or at 36 weeks' postmenstrual age. Initiation of bronchodilator therapy for the prevention of CLD had to occur within two weeks of birth. Treatment of infants with CLD had to be initiated before discharge from the neonatal unit. The intervention had to include administration of a bronchodilator by nebulisation or metered dose inhaler. The comparator was no intervention or placebo.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. Critical outcomes included: mortality within the trial period; CLD (defined as oxygen dependency at 28 days of life or at 36 weeks' postmenstrual age); adverse effects of bronchodilators, including hypokalaemia (low potassium levels in the blood), tachycardia, cardiac arrhythmia, tremor, hypertension and hyperglycaemia (high blood sugar); and pneumothorax. We used the GRADE approach to assess the certainty of the evidence for each outcome.

MAIN RESULTS

We included two randomised controlled trials in this review update. Only one trial provided useable outcome data. This trial was conducted in six neonatal intensive care units in France and Portugal, and involved 173 participants with a gestational age of less than 31 weeks. The infants in the intervention group received salbutamol for the prevention of CLD. The evidence suggests that salbutamol may result in little to no difference in mortality (risk ratio (RR) 1.08, 95% confidence interval (CI) 0.50 to 2.31; risk difference (RD) 0.01, 95% CI -0.09 to 0.11; low-certainty evidence) or CLD at 28 days (RR 1.03, 95% CI 0.78 to 1.37; RD 0.02, 95% CI -0.13 to 0.17; low-certainty evidence), when compared to placebo. The evidence is very uncertain about the effect of salbutamol on pneumothorax. The one trial with usable data reported that there were no relevant differences between groups, without providing the number of events (very low-certainty evidence). Investigators in this study did not report if side effects occurred. We found no eligible trials that evaluated the use of bronchodilator therapy for the treatment of infants with CLD. We identified no ongoing studies.

AUTHORS' CONCLUSIONS

Low-certainty evidence from one trial showed that inhaled bronchodilator prophylaxis may result in little or no difference in the incidence of mortality or CLD in preterm infants, when compared to placebo. The evidence is very uncertain about the effect of salbutamol on pneumothorax, and neither included study reported on the incidence of serious adverse effects. We identified no trials that studied the use of bronchodilator therapy for the treatment of CLD. Additional clinical trials are necessary to assess the role of bronchodilator agents in the prophylaxis or treatment of CLD. Researchers studying the effects of inhaled bronchodilators in preterm infants should include relevant clinical outcomes in addition to pulmonary mechanical outcomes.

Outpatient management of established bronchopulmonary dysplasia: An update

As the incidence of infants with bronchopulmonary dyspasia (BPD) has continued to rise, so has their rate of survival. Their medical management is often complex and requires the use of numerous therapies such as steroids, bronchodilators, diuretics and modalities to deliver supplemental oxygen and positive pressure. It also requires multi-disciplinary care to ensure adequate growth and to optimize neurodevelopmental outcomes. This review aims to discuss the most widely used therapies in the treatment of patients with established BPD. The focus will be on ongoing outpatient (post-neonatal intensive care) management of children with BPD. Since many of the mentioned therapies lack solid evidence to support their use, more high quality research, such as randomized controlled trials, is needed to assess their effectiveness using defined outcomes.

Role of Postnatal Corticosteroids in the Treatment or Prevention of Bronchopulmonary Dysplasia

As the frequency of viable low birth weight preterm babies increases, bronchopulmonary dysplasia (BPD), one of the most important morbidities in these babies, also increases. Using postnatal steroids to reduce the development of BPD has not been fully enlightened. Besides all prevention strategies for reducing the development of BPD, it is known that steroid therapy used in the 1st week of life could induce negative neuromotor development according to current data. It may be recommended to administer low-dose dexamethasone between 8 and 49 days in infants dependent on mechanical ventilators in the postnatal period. It is seen that the use of hydrocortisone in the early period does not cause negative neuromotor development, but it cannot prevent the development of BPD as much as dexamethasone. All intensive care units must have their steroid protocol for BPD and use steroids in cases when the BPD development scale score is >60-65% and should have a goal of trying to keep the cumulative dose at the lowest level.

Respiratory management in the premature neonate

INTRODUCTION

Advances in neonatal care have made possible the increased survival of extremely preterm infants. Even though there is widespread recognition of the harmful effects of mechanical ventilation on the developing lung, its use has become imperative in the management of micro-/nano-preemies. There is an increased emphasis on the use of less-invasive approaches such as minimally invasive surfactant therapy and non-invasive ventilation that have been proven to result in improved outcomes.

AREAS COVERED

Here, we review the evidence-based practices surrounding the respiratory management of extremely preterm infants including delivery room interventions, invasive and non-invasive ventilation approaches, and specific ventilator strategies in respiratory distress syndrome and bronchopulmonary dysplasia. Adjuvant relevant respiratory pharmacotherapies used in preterm neonates are also discussed.

EXPERT OPINION

Early use of non-invasive ventilation and use of less invasive surfactant administration are key strategies in the management of respiratory distress syndrome in preterm infants. Ventilator management in bronchopulmonary dysplasia must be tailored according to the individual phenotype. There is strong evidence to start caffeine early to improve respiratory outcomes, but evidence is lacking on the use of other pharmacological agents in preterm neonates, and an individualized approach has to be considered for their use.

Oscillatory Mechanics Response to Inhaled Bronchodilators in Very Preterm Infants: A Retrospective Study

OBJECTIVES

To identify short-term repeatability of forced oscillation technique (FOT) measurement of lung function, assess the lung function response to bronchodilators (BDs) by FOT, and prove the concept that only some very preterm infants manifest a change in lung mechanics in response to BD.

STUDY DESIGN

We retrospectively analyzed respiratory system resistance and respiratory system reactance measured by FOT (Fabian HFOi). The measurement short-term repeatability was assessed in 43 patients on 60 occasions; BD responsiveness was assessed using a different data set, including 38 measurements in 18 infants. The coefficient of repeatability was calculated as twice the SD of differences between measurements performed 15 minutes apart. We assessed BD responsiveness by measuring respiratory system resistance and respiratory system reactance before and 15 minutes after administering 200 mcg/kg of nebulized salbutamol. A positive response was defined as an improvement in respiratory system resistance or respiratory system reactance greater than the identified coefficient of repeatability.

RESULTS

The coefficient of repeatability was 7.5 cmH₂O∗s/L (21%) for respiratory system resistance and 6.3 cmH₂O∗s/L (21%) for respiratory system reactance. On average, respiratory system resistance did not change significantly following BD administration, though respiratory system reactance increased significantly (from -32.0 [-50.2, -24.4] to -27.9 [-38.1, -22.0] cmH₂O∗s/L, P < .001). Changes in respiratory system resistance or respiratory system reactance after BD were greater than the identified coefficient of repeatability in 8 infants (44%) on 13 (34%) occasions.

CONCLUSIONS

We identified a threshold to assess BD responsiveness by FOT in preterm infants. We speculate that FOT could be used to assess and personalize treatment with BD.

Pharmacotherapy in Bronchopulmonary Dysplasia: What Is the Evidence?

Bronchopulmonary Dysplasia (BPD) is a multifactorial disease affecting over 35% of extremely preterm infants born each year. Despite the advances made in understanding the pathogenesis of this disease over the last five decades, BPD remains one of the major causes of morbidity and mortality in this population, and the incidence of the disease increases with decreasing gestational age. As inflammation is one of the key drivers in the pathogenesis, it has been targeted by majority of pharmacological and non-pharmacological methods to prevent BPD. Most extremely premature infants receive a myriad of medications during their stay in the neonatal intensive care unit in an effort to prevent or manage BPD, with corticosteroids, caffeine, and diuretics being the most commonly used medications. However, there is no consensus regarding their use and benefits in this population. This review summarizes the available literature regarding these medications and aims to provide neonatologists and neonatal providers with evidence-based recommendations.

An Update on the Prevention and Management of Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is a common morbidity affecting preterm infants and is associated with substantial long-term disabilities. There has been no change in the incidence of BPD over the past 20 years, despite improvements in survival and other outcomes. The preterm lung is vulnerable to injuries occurring as a result of invasive ventilation, hyperoxia, and infections that contribute to the development of BPD. Clinicians caring for infants in the neonatal intensive care unit use multiple therapies for the prevention and management of BPD. Non-invasive ventilation strategies and surfactant administration via thin catheters are treatment approaches that aim to avoid volutrauma and barotrauma to the preterm developing lung. Identifying high-risk infants to receive postnatal corticosteroids and undergo patent ductus arteriosus closure may help to individualize care and promote improved lung outcomes. In infants with established BPD, outpatient management is complex and requires coordination from several specialists and therapists. However, most current therapies used to prevent and manage BPD lack solid evidence to support their effectiveness. Further research is needed with appropriately defined outcomes to develop effective therapies and impact the incidence of BPD.

Evidence for the Management of Bronchopulmonary Dysplasia in Very Preterm Infants

BACKGROUND

Very preterm birth often results in the development of bronchopulmonary dysplasia (BPD) with an inverse correlation of gestational age and birthweight. This very preterm population is especially exposed to interventions, which affect the development of BPD.

OBJECTIVE

The goal of our review is to summarize the evidence on these daily procedures and provide evidence-based recommendations for the management of BPD.

METHODS

We conducted a systematic literature research using MEDLINE/PubMed on antenatal corticosteroids, surfactant-replacement therapy, caffeine, ventilation strategies, postnatal corticosteroids, inhaled nitric oxide, inhaled bronchodilators, macrolides, patent ductus arteriosus, fluid management, vitamin A, treatment of pulmonary hypertension and stem cell therapy.

RESULTS

Evidence provided by meta-analyses, systematic reviews, randomized controlled trials (RCTs) and large observational studies are summarized as a narrative review.

DISCUSSION

There is strong evidence for the use of antenatal corticosteroids, surfactant-replacement therapy, especially in combination with noninvasive ventilation strategies, caffeine and lung-protective ventilation strategies. A more differentiated approach has to be applied to corticosteroid treatment, the management of patent ductus arteriosus (PDA), fluid-intake and vitamin A supplementation, as well as the treatment of BPD-associated pulmonary hypertension. There is no evidence for the routine use of inhaled bronchodilators and prophylactic inhaled nitric oxide. Stem cell therapy is promising, but should be used in RCTs only.