Early inhaled glucocorticoid therapy to prevent bronchopulmonary dysplasia

Efficacy and safety of different inhaled corticosteroids for bronchopulmonary dysplasia prevention in preterm infants: A systematic review and meta-analysis

BACKGROUND

This systematic review and meta-analysis aimed to evaluate the efficacy and safety of inhaled corticosteroids (budesonide, beclomethasone, or fluticasone propionate) in preventing bronchopulmonary dysplasia (BPD) for premature infants.

METHOD

Electronic databases, including PubMed, EMBASE, Web of science, Scopus, and Cochrane library, were searched from databases inception to January 2022 for eligible randomized controlled trials. Clinical outcomes such as BPD, mortality, BPD or death, adverse events, and neurodevelopmental outcomes were assessed.

RESULTS

Overall, budesonide was significantly associated with a reduction in BPD at 36 weeks' postmenstrual age (RR 0.48; 95 % CI [0.38, 0.62]) and patent ductus arteriosus (PDA) (RR 0.75; 95 % CI [0.63, 0.89]) compared with control treatments. Early longer duration inhalation of budesonide alone was associated with a lower risk of BPD at 36 weeks' postmenstrual age and PDA compared with controls. Early shorter duration intratracheal instillation of budesonide with surfactant as vehicle was associated with a lower risk of BPD at 36 weeks' postmenstrual age and all-cause mortality compared with surfactant. There was no statistically significant difference between budesonide and control groups regarding neurodevelopmental impairment. Beclomethasone and fluticasone propionate did not show any superior or inferior effect on clinical outcomes compared to control treatments.

CONCLUSION

These findings suggest that budesonide, especially intratracheal instillation of budesonide using surfactant as a vehicle, is a safe and effective option in preventing BPD for preterm infants. More well-design large-scale trials with long-term follow-ups are necessary to verify the present findings.

Corticosteroids for the prevention and treatment of bronchopulmonary dysplasia: an overview of systematic reviews

BACKGROUND

Bronchopulmonary dysplasia (BPD) remains an important complication of prematurity. Pulmonary inflammation plays a central role in the pathogenesis of BPD, explaining the rationale for investigating postnatal corticosteroids. Multiple systematic reviews (SRs) have summarised the evidence from numerous randomised controlled trials (RCTs) investigating different aspects of administrating postnatal corticosteroids. Besides beneficial effects on the outcome of death or BPD, potential short- and long-term harms have been reported.

OBJECTIVES

The primary objective of this overview was to summarise and appraise the evidence from SRs regarding the efficacy and safety of postnatal corticosteroids in preterm infants at risk of developing BPD.

METHODS

We searched the Cochrane Database of Systematic Reviews, MEDLINE, Embase, CINAHL, and Epistemonikos for SRs in April 2023. We included all SRs assessing any form of postnatal corticosteroid administration in preterm populations with the objective of ameliorating pulmonary disease. All regimens and comparisons were included. Two review authors independently checked the eligibility of the SRs comparing corticosteroids with placebo, and corticosteroids with different routes of administration and regimens. The included outcomes, considered key drivers in the decision to administer postnatal corticosteroids, were the composite outcome of death or BPD at 36 weeks' postmenstrual age (PMA), its individual components, long-term neurodevelopmental sequelae, sepsis, and gastrointestinal tract perforation. We independently assessed the methodological quality of the included SRs by using AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews) and ROBIS (Risk Of Bias In Systematic reviews) tools. We assessed the certainty of the evidence using GRADE. We provided a narrative description of the characteristics, methodological quality, and results of the included SRs.

MAIN RESULTS

We included nine SRs (seven Cochrane, two non-Cochrane) containing 87 RCTs, 1 follow-up study, and 9419 preterm infants, investigating the effects of postnatal corticosteroids to prevent or treat BPD. The quality of the included SRs according to AMSTAR 2 varied from high to critically low. Risk of bias according to ROBIS was low. The certainty of the evidence according to GRADE ranged from very low to moderate. Early initiated systemic dexamethasone (< seven days after birth) likely has a beneficial effect on death or BPD at 36 weeks' PMA (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.81 to 0.95; number needed to treat for an additional beneficial outcome (NNTB) 16, 95% CI 10 to 41; I2 = 39%; 17 studies; 2791 infants; moderate-certainty evidence) and on BPD at 36 weeks' PMA (RR 0.72, 95% CI 0.63 to 0.82; NNTB 13, 95% CI 9 to 21; I2 = 39%; 17 studies; 2791 infants; moderate-certainty evidence). Early initiated systemic hydrocortisone may also have a beneficial effect on death or BPD at 36 weeks' PMA (RR 0.90, 95% CI 0.82 to 0.99; NNTB 18, 95% CI 9 to 594; I2 = 43%; 9 studies; 1376 infants; low-certainty evidence). However, these benefits are likely accompanied by harmful effects like cerebral palsy or neurosensory disability (dexamethasone) or gastrointestinal perforation (both dexamethasone and hydrocortisone). Late initiated systemic dexamethasone (≥ seven days after birth) may have a beneficial effect on death or BPD at 36 weeks' PMA (RR 0.75, 95% CI 0.67 to 0.84; NNTB 5, 95% CI 4 to 9; I2 = 61%; 12 studies; 553 infants; low-certainty evidence), mostly contributed to by a beneficial effect on BPD at 36 weeks' PMA (RR 0.76, 95% CI 0.66 to 0.87; NNTB 6, 95% CI 4 to 13; I2 = 14%; 12 studies; 553 infants; low-certainty evidence). No harmful side effects were shown in the outcomes chosen as key drivers to the decision to start or withhold late systemic dexamethasone. No effects, either beneficial or harmful, were found in the subgroup meta-analyses of late hydrocortisone studies. Early initiated inhaled corticosteroids probably have a beneficial effect on death and BPD at 36 weeks' PMA (RR 0.86, 95% CI 0.75 to 0.99; NNTB 19, 95% CI not applicable; I2 = 0%; 6 studies; 1285 infants; moderate-certainty evidence), with no apparent adverse effects shown in the SRs. In contrast, late initiated inhaled corticosteroids do not appear to have any benefits or harms. Endotracheal instillation of corticosteroids (budesonide) with surfactant as a carrier likely has a beneficial effect on death or BPD at 36 weeks' PMA (RR 0.60, 95% CI 0.49 to 0.74; NNTB 4, 95% CI 3 to 6; I2 = 0%; 2 studies; 381 infants; moderate-certainty evidence) and on BPD at 36 weeks' PMA. No evidence of harmful effects was found. There was little evidence for effects of different starting doses or timing of systemic corticosteroids on death or BPD at 36 weeks' PMA, but potential adverse effects were observed for some comparisons. Lowering the dose might result in a more unfavourable balance of benefits and harms. Moderately early initiated systemic corticosteroids, compared with early systemic corticosteroids, may result in a higher incidence of BPD at 36 weeks' PMA. Pulse dosing instead of continuous dosing may have a negative effect on death and BPD at 36 weeks' PMA. We found no differences for the comparisons of inhaled versus systemic corticosteroids.

AUTHORS' CONCLUSIONS

This overview summarises the evidence of nine SRs investigating the effect of postnatal corticosteroids in preterm infants at risk for BPD. Late initiated (≥ seven days after birth) systemic administration of dexamethasone is considered an effective intervention to reduce the risk of BPD in infants with a high risk profile for BPD, based on a favourable balance between benefits and harms. Endotracheal instillation of corticosteroids (budesonide) with surfactant as a carrier is a promising intervention, based on the beneficial effect on desirable outcomes without (so far) negative side effects. Pending results of ongoing large, multicentre RCTs investigating both short- and long-term effects, endotracheal instillation of corticosteroids (budesonide) with surfactant as a carrier is not appropriate for clinical practice at present. Early initiated (< seven days after birth) systemic dexamethasone and hydrocortisone and late initiated (≥ seven days after birth) hydrocortisone are considered ineffective interventions, because of an unfavourable balance between benefits and harms. No conclusions are possible regarding early and late inhaled corticosteroids, as more research is needed.

Late (≥ 7 days) inhaled corticosteroids to reduce bronchopulmonary dysplasia in preterm infants

BACKGROUND

Bronchopulmonary dysplasia (BPD), defined as oxygen dependence at 36 weeks' postmenstrual age (PMA), remains an important complication of prematurity. Pulmonary inflammation plays a central role in the pathogenesis of BPD. Attenuating pulmonary inflammation with postnatal systemic corticosteroids reduces the incidence of BPD in preterm infants but may be associated with an increased risk of adverse neurodevelopmental outcomes. Local administration of corticosteroids via inhalation may be an effective and safe alternative.

OBJECTIVES

To assess the benefits and harms of inhaled corticosteroids versus placebo, initiated between seven days of postnatal life and 36 weeks' postmenstrual age, to preterm infants at risk of developing bronchopulmonary dysplasia.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, and three trials registries to August 2022. We searched conference proceedings and the reference lists of retrieved articles for additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing inhaled corticosteroids to placebo, started between seven days' postnatal age (PNA) and 36 weeks' PMA, in infants at risk of BPD. We excluded trials investigating systemic corticosteroids versus inhaled corticosteroids.

DATA COLLECTION AND ANALYSIS

We collected data on participant characteristics, trial methodology, and inhalation regimens. The primary outcomes were mortality, BPD, or both at 36 weeks' PMA. Secondary outcomes included short-term respiratory outcomes (mortality or BPD at 28 days' PNA, failure to extubate, total days of mechanical ventilation and oxygen use, and need for systemic corticosteroids) and adverse effects. We contacted the trial authors to verify the validity of extracted data and to request missing data. We analysed all data using Review Manager 5. Where possible, we reported the results of meta-analyses using risk ratios (RRs) and risk differences (RDs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, along with their 95% confidence intervals (CIs). We analysed ventilated and non-ventilated participants separately. We used the GRADE approach to assess the certainty of the evidence.

MAIN RESULTS

We included seven trials involving 218 preterm infants in this review. We identified no new eligible studies in this update. The evidence is very uncertain regarding whether inhaled corticosteroids affects the combined outcome of mortality or BPD at 36 weeks' PMA (RR 1.10, 95% CI 0.74 to 1.63; RD 0.07, 95% CI -0.21 to 0.34; 1 study, 30 infants; very low-certainty) or its separate components: mortality (RR 3.00, 95% CI 0.35 to 25.78; RD 0.07, 95% CI -0.08 to 0.21; 3 studies, 61 infants; very low-certainty) and BPD (RR 1.00, 95% CI 0.59 to 1.70; RD 0.00, 95% CI -0.31 to 0.31; 1 study, 30 infants; very low-certainty) at 36 weeks' PMA. Inhaled corticosteroids may reduce the need for systemic corticosteroids, but the evidence is very uncertain (RR 0.51, 95% CI 0.26 to 1.00; RD -0.22, 95% CI -0.42 to -0.02; number needed to treat for an additional beneficial outcome 5, 95% CI 2 to 115; 4 studies, 74 infants; very low-certainty). There was a paucity of data on short-term and long-term adverse effects. Despite a low risk of bias in the individual studies, we considered the certainty of the evidence for all comparisons discussed above to be very low, because the studies had few participants, there was substantial clinical heterogeneity between studies, and only three studies reported the primary outcome of this review.

AUTHORS' CONCLUSIONS

Based on the available evidence, we do not know if inhaled corticosteroids initiated from seven days of life in preterm infants at risk of developing BPD reduces mortality or BPD at 36 weeks' PMA. There is a need for larger randomised placebo-controlled trials to establish the benefits and harms of inhaled corticosteroids.

A systematic review and meta-analysis of pulmonary surfactant combined with budesonide in the treatment of neonatal respiratory distress syndrome

BACKGROUND

Neonatal respiratory distress syndrome (NRDS), if caused by a lack of pulmonary surfactant (PS), leads to progressive alveolar collapse. Glucocorticoids have anti-inflammatory and anti-allergic effects and can reduce bronchial and pulmonary edema. This research hopes to systematically evaluate the efficacy and safety of animal-derived PS combined with the glucocorticoid drug budesonide in the treatment of NRDS.

METHODS

Electronic databases (i.e., Wanfang, Weipu, CNKI, PubMed, Embase, Cochrane Library) were searched from inception until May 30th, 2021. Studies relevant to the treatment of pulmonary surfactant combined with budesonide in the treatment of neonatal respiratory distress syndrome were identified. Consequently, all the studies that met the inclusion criteria were considered qualified for screening. For the meta-analysis, all data were analyzed using RevMan 5.3 software. Furthermore, subgroup analysis was performed to evaluate the administration method of budesonide (nebulized inhalation, intratracheal instillation) combined with intratracheal instillation of pulmonary surfactant.

RESULTS

A total of 10 articles were included in this study, involving 527 children. This meta-analysis suggests that the treatment of intratracheal infusion of pulmonary surfactant combined with budesonide therapy can effectively (I) reduce the time of mechanical ventilation (OR =-1.72,95% CI: -2.44 to -1.01, P<0.00001); (II) reduce the length of stay (OR =-5.17, 95% CI: -9.35 to -0.99, P=0.02); (III) reduce the incidence of bronchopulmonary dysplasia (BPD) (OR =0.52, 95% CI: 0.39-0.68, P<0.00001); and (IV) reduce the incidence of BPD (RR =0.73, 95% CI: 0.40-1.35, P=0.32). There was no significant difference in the incidence of retinopathy of prematurity (ROP), necrotizing enterocolitis (NEC), patent ductus arteriosus (PDA), or sepsis between the experimental group and the control group.

DISCUSSION

The treatment of animal-derived pulmonary surfactant combined with budesonide can effectively shorten the hospital stay and reduce the time of invasive mechanical ventilation and the incidence of BPD. Meanwhile, it does not increase the risk of related complications or death. This approach can be applied clinically.

Current evidence for prenatal and postnatal corticosteroids in preterm infants

Antenatal corticosteroids undoubtedly save many lives and improve the quality of many others. However, the currently accepted dosage schedule has been in place since 1972, and recent studies have suggested that beneficial effects may be seen with less. Most but not all studies of long-term outcome show no adverse effects. The use of antenatal corticosteroids in women with COVID-19 raises important questions regarding potential risks and benefits. However, currently, most authorities recommend continuing according to published guidelines. With regard to postnatal corticosteroids, alternatives to systemic dexamethasone, the somewhat tainted standard of care, show promise in preventing bronchopulmonary dysplasia without adverse effects. Systemic hydrocortisone and inhaled corticosteroids are of note. The mixture of surfactant and corticosteroids deserves particular attention in the coming years.

Assessment of Postnatal Corticosteroids for the Prevention of Bronchopulmonary Dysplasia in Preterm Neonates: A Systematic Review and Network Meta-analysis

IMPORTANCE

The safety of postnatal corticosteroids used for prevention of bronchopulmonary dysplasia (BPD) in preterm neonates is a controversial matter, and a risk-benefit balance needs to be struck.

OBJECTIVE

To evaluate 14 corticosteroid regimens used to prevent BPD: moderately early-initiated, low cumulative dose of systemic dexamethasone (MoLdDX); moderately early-initiated, medium cumulative dose of systemic dexamethasone (MoMdDX); moderately early-initiated, high cumulative dose of systemic dexamethasone (MoHdDX); late-initiated, low cumulative dose of systemic dexamethasone (LaLdDX); late-initiated, medium cumulative dose of systemic dexamethasone (LaMdDX); late-initiated, high cumulative dose of systemic dexamethasone (LaHdDX); early-initiated systemic hydrocortisone (EHC); late-initiated systemic hydrocortisone (LHC); early-initiated inhaled budesonide (EIBUD); early-initiated inhaled beclomethasone (EIBEC); early-initiated inhaled fluticasone (EIFLUT); late-initiated inhaled budesonide (LIBUD); late-initiated inhaled beclomethasone (LIBEC); and intratracheal budesonide (ITBUD).

DATA SOURCES

PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, World Health Organization's International Clinical Trials Registry Platform (ICTRP), and CINAHL were searched from inception through August 25, 2020.

STUDY SELECTION

In this systematic review and network meta-analysis, the randomized clinical trials selected included preterm neonates with a gestational age of 32 weeks or younger and for whom a corticosteroid regimen was initiated within 4 weeks of postnatal age. Peer-reviewed articles and abstracts in all languages were included.

DATA EXTRACTION AND SYNTHESIS

Two independent authors extracted data in duplicate. Network meta-analysis used a bayesian model.

MAIN OUTCOMES AND MEASURES

Primary combined outcome was BPD, defined as oxygen requirement at 36 weeks' postmenstrual age (PMA), or mortality at 36 weeks' PMA. The secondary outcomes included 15 safety outcomes.

RESULTS

A total of 62 studies involving 5559 neonates (mean [SD] gestational age, 26 [1] weeks) were included. Several regimens were associated with a decreased risk of BPD or mortality, including EHC (risk ratio [RR], 0.82; 95% credible interval [CrI], 0.68-0.97); EIFLUT (RR, 0.75; 95% CrI, 0.55-0.98); LaHdDX (RR, 0.70; 95% CrI, 0.54-0.87); MoHdDX (RR, 0.64; 95% CrI, 0.48-0.82); ITBUD (RR, 0.73; 95% CrI, 0.57-0.91); and MoMdDX (RR, 0.61; 95% CrI, 0.45-0.79). Surface under the cumulative ranking curve (SUCRA) value ranking showed that MoMdDX (SUCRA, 0.91), MoHdDX (SUCRA, 0.86), and LaHdDX (SUCRA, 0.76) were the 3 most beneficial interventions. ITBUD (RR, 4.36; 95% CrI, 1.04-12.90); LaHdDX (RR, 11.91; 95% CrI, 1.64-44.49); LaLdDX (RR, 6.33; 95% CrI, 1.62-18.56); MoHdDX (RR, 4.96; 95% CrI, 1.14-14.75); and MoMdDX (RR, 3.16; 95% CrI, 1.35-6.82) were associated with more successful extubation from invasive mechanical ventilation. EHC was associated with a higher risk of gastrointestinal perforation (RR, 2.77; 95% CrI, 1.09-9.32). MoMdDX showed a higher risk of hypertension (RR, 3.96; 95% CrI, 1.10-30.91). MoHdDX had a higher risk of hypertrophic cardiomyopathy (RR, 5.94; 95% CrI, 1.95-18.11).

CONCLUSIONS AND RELEVANCE

This study suggested that MoMdDX may be the most appropriate postnatal corticosteroid regimen for preventing BPD or mortality at a PMA of 36 weeks, albeit with a risk of hypertension. The quality of evidence was low.

Early inhaled budesonide in extremely preterm infants decreases long-term respiratory morbidity

BACKGROUND

There is no strict correlation between early bronchopulmonary dysplasia and long-term respiratory disease. Early inhaled corticosteroids seem to reduce the incidence of bronchopulmonary dysplasia, but the long-term outcome remains unknown.

RESEARCH QUESTION

The aim of this study was to evaluate the effect of early inhaled corticosteroids on chronic respiratory morbidity.

METHODS

Fifty-nine survivors from the Prague cohort included in Neonatal European Study of Inhaled Steroids underwent further follow-up comprising of respiratory morbidity monitoring during the first 2 years of life followed by objective lung function testing performed at the age of 5.9 years (range 5-7 years). Both outcomes were pursued and finalized before the unblinding of budesonide subgroups.

RESULTS

Fifty randomized (budesonide vs placebo group, 56% vs 44%) survivors were included in the study. Spirometry was successfully performed in 48 children. No statistically significant differences were found in the lung function test (forced expiratory flow [FEF] - FEF₇₅ , FEF_50, FEF₂₅ , and FEF_25-75; FEV₁ , forced vital capacity [FVC], FEV₁ /FVC) although mild trend to the improvement of expiratory flow pattern was observed in the budesonide group (median z-score of FEV₁ /FVC -0.376 vs -0.983, P = .13; median z-score of FEF_25-75 -1.004 vs -1.458, P = .13; median z-score of FEF₇₅ -0.527 vs -0.996, P = .17). Children assigned to budesonide had a significantly lower rate of symptoms of chronic lung disease (34.6% vs 68.2%; P = .04) than children assigned to placebo.

INTERPRETATION

Our study suggests that early inhaled budesonide was associated with the trend to the improvement of functional lung parameters and with a lower rate of symptoms of chronic lung disease within the first 2 years of life.

Biophysical and chemical stability of surfactant/budesonide and the pulmonary distribution following intra-tracheal administration

Intra-tracheal instillation of budesonide using surfactant as a vehicle significantly decreased the incidence of bronchopulmonary dysplasia or death in preterm infants. The formularity of surfactant supplemented with budesonide and biophysical and chemical stability of the suspension has not been well reported. The aims are to investigate the biophysical and chemical stability of two surfactant preparations, Survanta and Curosurf, supplemented with budesonide. Biophysical property of the surface tension of Survanta and Survanta/budesonide suspension and of Curosurf and Curosurf/budesonide suspension was conducted by a pulsating bubble surfactometer and by a drop shape tensiometer. Chemical stability of Survanta/budesonide and of Curosurf/budesonide suspensions was tested by high-performance liquid chromatography analysis (HPLC). Pulmonary distribution of Survanta/¹⁸F-budesonide suspension was examined by a Nano/PET digital scan in rats. The Marangoni effect of Survanta, Curosurf, and budesonide was tested by digital high speed photography. For Survanta supplemented with budesonide, with a concentration ratio of ≥50, the surface tension-lowering activity was minimally affected. Similarly, the surface tension-lowering activity of Curosurf was not significantly affected by addition of budesonide, if the concentration ratio was ≥160. With these concentration ratios of both suspensions, HPLC analysis revealed no new compounds identified. Curosurf as compared to Survanta exhibited a significantly higher Marangoni effect. We conclude that with current dosage recommended for Survanta and Curosurf, both surfactant/budesonide suspensions are biophysically and chemically stable. Both surfactants can act as an effective vehicle for budesonide delivery.

Efficacy and safety of pulmonary application of corticosteroids in preterm infants with respiratory distress syndrome: a systematic review and meta-analysis

BACKGROUND

Systemic corticosteroids as the frontline treatment of respiratory distress syndrome (RDS) in preterm infants are associated with adverse effects on growth and neurodevelopmental outcome, but the pulmonary administration of steroids may help prevent the development of bronchopulmonary dysplasia (BPD) without these side effects.

OBJECTIVES

To evaluate the efficacy and safety of pulmonary application of corticosteroids in preterm infants with RDS.

METHODS

MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, the WHO's International Clinical Trials Registry and grey literature were searched with no restriction on date and language of publication from inception to May 2016. Using a random-effect model, we pooled data from randomised controlled trials (RCTs) comparing inhaled or endotracheal corticosteroids with the standard of care, placebo or no other intervention in preterm infants with RDS.

RESULTS

We identified 873 potential citations and included 12 unique RCTs. Pulmonary corticosteroid therapy was associated with a significant reduction in the composite outcome of BPD or death (relative risk (RR) 0.85, 95% CI 0.76 to 0.96). Pulmonary application of corticosteroids significantly reduced the incidence of patent ductus arteriosus (PDA) (RR 0.82, 95% CI 0.74 to 0.92) and pneumonia (RR 0.57, 95% CI 0.35 to 0.92). There was no evidence of a significant difference regarding the risk of neurodevelopmental impairment or other side effects.

CONCLUSIONS

Pulmonary administration of corticosteroids reduces the incidence of BPD or death, pneumonia, PDA without causing any major side effects in preterm infants with RDS.

Bronchopulmonary dysplasia: Pathogenesis and treatment

Bronchopulmonary dysplasia (BPD) is a form of chronic lung disease of infancy, which mostly affects premature infants with significant morbidity and mortality. Premature infants who require to be treated for conditions including respiratory distress syndrome have a higher risk of developing BPD. In spite of the improvement in clinical methods, the incidence of BPD has not reduced. In the present review, the pathogenesis of BPD is described along with the treatments available at present and the role of nursing in the management of BPD. Emerging preventive therapies for BPD are also discussed, including the use of recombinant human superoxide dismutase, which has been proven effective in reducing respiratory injury and its long-term effects.

The Effect of Inhaled Budesonide on the Prevention of Chronic Lung Disease in Premature Neonates with Respiratory Distress Syndrome

BACKGROUND

Considering all the latest achievements in neonatal respiratory care, bronchopulmonary dysplasia (BPD) is still among the most prevalent morbidity causes in premature infants. Involvement in this process results in longer period of hospitalization for the newborn and in the long run makes the living conditions more difficult. Taking the multifactorial pathogenesis into account, approaches to tackle chronic lung disease (CLD) are mainly focused on interventions and prevention procedures. This study tries to investigate the potential capability of inhaled budesonide in the prevention of BPD in newborns with gestational age of <28 weeks with the respiratory distress syndrome (RDS).

METHODS

This study was a randomized clinical trial done on seventy newborns with gestational ages of 23-28 weeks with RDS in Isfahan Shahid Beheshti Educational Hospital from June 2014 to April 2016. Patients were randomly assigned to two groups of intervention with budesonide and control. There were 35 newborns in each group. Upon recording demographic characteristics, the newborns in two groups were compared based on the length of noninvasive ventilation, the need for invasive mechanical ventilation, the number of surfactant administrations, pneumothorax, intraventricular hemorrhage, patent ductus arteriosus (PDA), CLD, and death.

RESULTS

The length of the need for nasal continuous positive airway pressure showed no statistically significant difference between the groups (P = 0.54). The number of newborns who needed invasive mechanical ventilation also revealed no meaningful difference (P = 0.14). Similarly, the number of newborns who were characterized as affected by CLD also showed no significant difference between the groups (P = 0.053). Moreover, the number of newborns who experienced pneumothorax was not significantly different for the groups (P = 0.057). The number of newborns who received three administrations of surfactant had also no statistically meaningful difference between the groups (P = 0.69). However, the number of newborns who received two doses of surfactant was statistically lower in budesonide intervention group than the control (P = 0.041). The prevalence of intraventricular hemorrhage with degrees of I, II, and III also showed no statistically meaningful difference between the groups with P = 0.74, 0.32, and 0.49, respectively. The occurrence of PDA had no meaningful difference between the groups (P = 0.66). Relative death cases also revealed no significant difference between the groups (P = 0.53).

CONCLUSIONS

The current study revealed a decrease in CLD prevalence for newborns in interventional group; however, this decrease was not statistically meaningful. The newborns, in the intervention group, who had received two doses of surfactant (survanta) showed a significant decrease, which can be the basis for further research in this field.

Airway administration of corticosteroids for prevention of bronchopulmonary dysplasia in premature infants: a meta-analysis with trial sequential analysis

BACKGROUND

Uncertainly prevails with regard to the use of inhalation or instillation steroids to prevent bronchopulmonary dysplasia in preterm infants. The meta-analysis with sequential analysis was designed to evaluate the efficacy and safety of airway administration (inhalation or instillation) of corticosteroids for preventing bronchopulmonary dysplasia (BPD) in premature infants.

METHODS

We searched MEDLINE, EMBASE, CINAHL, and Cochrane CENTRAL from their inceptions to February 2017. All published randomized controlled trials (RCTs) evaluating the effect of airway administration of corticosteroids (AACs) vs placebo or systemic corticosteroid in prematurity were included. All meta-analyses were performed using Review Manager 5.3.

RESULTS

Twenty five RCTs retrieved (n = 3249) were eligible for further analysis. Meta-analysis and trial sequential analysis corrected the 95% confidence intervals estimated a lower risk of the primary outcome of BPD (relative risk 0.71, adjusted 95% confidence interval 0.57-0.87) and death or BPD (relative risk 0.81, adjusted 95% confidence interval 0.71-0.97) in AACs group than placebo and it is equivalent for preventing BPD than systemic corticosteroids. Moreover, AACs fail to increasing risk of death compared with placebo (relative risk 0.90, adjusted 95% confidence interval 0.40-2.03) or systemic corticosteroids (relative risk 0.81, 95% confidence interval 0.62-1.06).

CONCLUSIONS

Our findings suggests that AACs (especially instillation of budesonide using surfactant as a vehicle) are an effective and safe option for preventing BPD in preterm infants. Furthermore, the appropriate dose and duration, inhalation or instillation with surfactant as a vehicle and the long-term safety of airway administration of corticosteroids needs to be assessed in large trials.

Development and Evaluation of a Family of Human Face and Upper Airway Models for the Laboratory Testing of Orally Inhaled Products

Many orally inhaled products are supplied with a facemask instead of a mouthpiece, enabling aerosolized medication to be transferred from the inhaler to the lungs when the user lacks the capability to use a mouthpiece. Until recently, laboratory evaluation of an orally inhaled product-facemask was frequently undertaken by removing the facemask, treating the facemask adapter as being equivalent to a mouthpiece. Measurements of delivered drug mass were therefore subject to bias arising from the absence of dead volume, had the facemask been present. We have described the development of the Aerosol Delivery to an Anatomic Model (ADAM) infant, small child, and adult faces and upper airways, and their subsequent evaluation. Each model possesses physical features of appropriate size, and the soft tissues are also simulated. Rudimentary underlying bony structure is also present, because its purpose is only to provide support, enabling the mechanical response of the facial soft tissues when a facemask is applied to be realized. A realistic upper airway (nasopharynx for the infant model, naso- and oropharynx for the child and oropharynx for the adult models) is also incorporated, so that each model can be used to determine the mass of inhaled medication likely to penetrate as far as the lungs where therapy is intended to be applied. Measurements of the mass of pressurized metered-dose inhaler-delivered salbutamol at a filter distal to the upper airway of each model, simulating age-appropriate tidal breathing, were remarkably consistent, almost all being in the range 0.3 to 1.0 μg/kg across the model age ranges, when expressed as a fraction of body weight.

Efficacy of glucocorticoids, vitamin A and caffeine therapies for neonatal mortality in preterm infants: a network meta-analysis

Introduction

The paper aimed to evaluate the efficacy of different therapies in improving survival among preterm infants.

Materials and Methods

PubMed and Embase were searched from inception to 2017. We assessed studies for eligibility and extracted data. A Bayesian random-effects model was used to evaluate different therapies combined direct comparisons with indirect evidence. Consistency analysis was achieved using node-splitting plots. Surface under the cumulative ranking curve (SUCRA) was calculated to rank different therapies. Rankings of the competing therapies were also performed.

Results

A total of 42 randomized controlled trials (RCTs) were included for the network meta-analysis. Forest plots demonstrated that dexamethasone (OR = 10.13, 95% CrI: 5.11 to 17.89) and vitamin A (OR = 28.44, 95% CrI: 14.66 to 42.11) is superior to placebo in duration of oxygen supplementation while vitamin A (OR = −29.76, 95% CrI: −57.66 to −1.75) is inferior to placebo with regard to duration of hospitalization. Also, dexamethasone (OR = 0.42, 95% CrI: 0.24 to 0.68) showed lower incidence rate of BPD.

SUCRA results showed the superiority of Budesonide based on primary efficacy outcomes. In addition, dexamethasone also showed high efficacy ranking in duration of ventilation, duration of oxygen supplementation, and occurrence of BPD. Hydrocortisone was effective in reducing neonatal mortality. No significant difference was found among these drugs.

Conclusions

No significant heterogeneity was found among these drugs. In general, budesonide might have the potential to be the optimal drug for its efficacy in reducing neonatal mortality and BPD, the two most essential outcome measures. Dexamethasone might be the suboptimal drug.

The use of inhaled corticosteroids in chronically ventilated preterm infants

Bronchopulmonary dysplasia (BPD) is the most usual reason for preterm infants to require chronic mechanical ventilation. Inflammation is a key factor underlying the lung injury leading to the development of BPD, and the rationale for use of corticosteroids in the management of ventilator-dependent preterm infants is based on their anti-inflammatory effects. Because systemic corticosteroids are associated with significant adverse effects in preterm infants, attention has turned to the use of inhaled corticosteroids (ICS) as a potentially safer therapy for BPD. The aim of this review is to discuss what is known about the efficacy and safety of ICS in chronically ventilated preterm infants. However, this has been a challenge since there is a paucity of high-grade evidence for the use of ICS in these patients. Thus, there is a real need for well-powered randomized controlled trials examining short- and long-term outcomes of ICS use in this population.

Late (≥ 7 days) inhalation corticosteroids to reduce bronchopulmonary dysplasia in preterm infants

BACKGROUND

Bronchopulmonary dysplasia (BPD), defined as oxygen dependence at 36 weeks postmenstrual age (PMA), remains an important complication of prematurity. Pulmonary inflammation plays a central role in the pathogenesis of BPD. Attenuating pulmonary inflammation with postnatal systemic corticosteroids reduces the incidence of BPD in preterm infants but may be associated with an increased risk of adverse neurodevelopmental outcomes. Local administration of corticosteroids via inhalation might be an effective and safe alternative.

OBJECTIVES

To determine if administration of inhalation corticosteroids after the first week of life until 36 weeks PMA to preterm infants at high risk of developing BPD is effective and safe in reducing the incidence of death and BPD as separate or combined outcomes.

SEARCH METHODS

We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2017, Issue 4), MEDLINE via PubMed (1966 to 19 May 2017), Embase (1980 to 19 May 2017), and CINAHL (1982 to 19 May 2017). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised controlled trials and quasi-randomised trials.

SELECTION CRITERIA

We included randomised controlled trials comparing inhalation corticosteroids, started ≥ 7 days postnatal age (PNA) but before 36 weeks PMA, to placebo in ventilated and non-ventilated infants at risk of BPD. We excluded trials investigating systemic corticosteroids versus inhalation corticosteroids.

DATA COLLECTION AND ANALYSIS

We collected data on participant characteristics, trial methodology, and inhalation regimens. The primary outcome was death or BPD at 36 weeks PMA. Secondary outcomes were the combined outcome death or BPD at 28 days PNA, the seperate outcomes of death and BPD at both 28 days PNA, and at 36 weeks PMA, and short-term respiratory outcomes, such as failure to extubate; total days of mechanical ventilation and oxygen use; and the need for systemic corticosteroids. We contacted the original trialists to verify the validity of extracted data and to provide missing data. We analysed all data using Review Manager 5. When possible, we performed meta-analysis using typical risk ratio (RR) for dichotomous outcomes and weighted mean difference (WMD) for continuous outcomes along with their 95% confidence intervals (CI). We analysed ventilated and non-ventilated participants separately.We used the GRADE approach to assess the quality of the evidence.

MAIN RESULTS

We included eight trials randomising 232 preterm infants in this review. Inhalation corticosteroids did not reduce the separate or combined outcomes of death or BPD. The meta-analyses of the studies showed a reduced risk in favor of inhalation steroids regarding failure to extubate at seven days (typical RR (TRR) 0.80, 95% CI 0.66 to 0.98; 5 studies, 79 infants) and at the latest reported time point after treatment onset (TRR 0.60, 95% CI 0.45 to 0.80; 6 studies, 90 infants). However, both analyses showed increased statistical heterogeneity (I² statistic 73% and 86%, respectively). Furthermore, inhalation steroids did not impact total duration of mechanical ventilation or oxygen dependency. There was a trend toward a reduction in the use of systemic corticosteroids in infants receiving inhalation corticosteroids (TRR 0.51, 95% CI 0.26 to 1.00; 4 studies, 74 infants; very low-quality evidence). There was a paucity of data on short- and long-term adverse effects. Our results should be interpreted with caution because the total number of randomised participants is relatively small, and most trials differed considerably in participant characteristics, inhalation therapy, and outcome definitions.

AUTHORS' CONCLUSIONS

Based on the results of the currently available evidence, inhalation corticosteroids initiated at ≥ 7 days of life for preterm infants at high risk of developing BPD cannot be recommended at this point in time. More and larger randomised, placebo-controlled trials are needed to establish the efficacy and safety of inhalation corticosteroids.

In Vitro Assessment of Small Charged Pharmaceutical Aerosols in a Model of a Ventilated Neonate

Aerosolized medications may benefit infants receiving mechanical ventilation; however, the lung delivery efficiency of these aerosols is unacceptably low. In vitro experiments were conducted to evaluate aerosol delivery through conventional and modified ventilation systems to the end of a 3mm endotracheal tube (ETT) under steady state and realistic cyclic flow conditions. System modifications were employed to investigate the use of small charged particles and included streamlined components, a reduction in nebulizer liquid flow rate, synchronization with inspiration, and implementation of a previously designed low-flow induction charger (LF-IC), which was further modified in this study. Cyclic flow experiments implemented a modern ventilator with bias airflow and an inline flow meter, both of which are frequently excluded from in vitro tests but included in clinical practice. The modified LF-IC system demonstrated superior delivery efficiency to the end of the ETT (34%) compared with the commercial system (~1.3%) operating under cyclic ventilation conditions. These findings indicate that commercial systems still provide very low lung delivery efficiencies despite decades of innovation. In contrast, the modified system increased dose delivery to the end of the ETT by 26-fold. Despite initial concerns, the charged aerosol could be efficiently delivered through the small diameter ETT and reach the lungs. Future studies will be required to determine if the applied particle charge can eliminate expected high exhalation aerosol loss and will require the development of a realistic lung model.

[Early postnatal application of glucocorticoids for preventing bronchopulmonary dysplasia in preterm infants: a Meta analysis]

OBJECTIVE

To study the clinical effect and safety of early postnatal application of glucocorticoids in the prevention of bronchopulmonary dysplasia (BPD) in preterm infants.

METHODS

The databases including PubMed, Cochrane Library, Embase, CNKI, Wanfang Data, and VIP were comprehensively searched for articles on early postnatal application of glucocorticoids in the prevention of BPD in preterm infants published up to June 2016. Review Manager 5.3 was used for the Meta analysis of 16 randomized controlled trials (RCTs) that met the inclusion criteria.

RESULTS

A total of 2 962 participants were enrolled in the 16 RCTs, with 1 486 patients in the trial group and 1 476 in the control group. The Meta analysis showed that early postnatal application of glucocorticoids reduced the incidence rate of BPD at a corrected gestational age of 36 weeks (OR=0.73, 95%CI: 0.61-0.87, P=0.0004), but there was an increase in the risk of hyperglycemia (OR=1.61, 95%CI: 1.24-2.09, P=0.0003), hypertension (OR=1.63, 95%CI: 1.11-2.38, P=0.01), and intestinal perforation (OR=1.51, 95%CI: 1.12-2.04, P=0.007).

CONCLUSIONS

At present, it is not recommended to use glucocorticoids to prevent BPD in preterm infants. Its advantages and disadvantages need further studies, with special focuses on the adverse effects of hyperglycemia, hypertension, and intestinal perforation.

Drug versus placebo randomized controlled trials in neonates: A review of ClinicalTrials.gov registry

BACKGROUND

Despite specific initiatives and identified needs, most neonatal drugs are still used off-label, with variable dosage administrations and schedules. In high risk preterm and term neonates, drug evaluation is challenging and randomized controlled trials (RCT) are difficult to conduct and even more is the use of a placebo, required in the absence of a reference validated drug to be used as comparator.

METHODS

We analyzed the complete ClinicalTrials.gov registry 1) to describe neonatal RCT involving a placebo, 2) to report on the medical context and ethical aspects of placebo use.

RESULTS

Placebo versus drug RCT (n = 146), either prevention trials (n = 57, 39%) or therapeutic interventions (n = 89, 61%), represent more than a third of neonatal trials registered in the National Institute of Health clinical trial database (USA) since 1999. They mainly concerned preterm infants, evaluating complications of prematurity. Most trials were conducted in the USA, were single centered, and funded by non-profit organizations. For the three top drug trials evaluating steroids (n = 13, 9.6%), erythropoietin (EPO, n = 10, 6.8%) and nitric oxide (NO, n = 9, 6.2%), the objectives of the trial and follow-up were analyzed in more details.

CONCLUSION

Although a matter of debate, the use of placebo should be promoted in neonates to evaluate a potential new treatment, in the absence of reference drug. Analysis of the trials evaluating steroids showed that long-term follow-up of exposed patients, although required by international guidelines, is frequently missing and should be planned to collect additional information and optimize drug evaluation in these high-risk patients.

[Clinical efficacy of pulmonary surfactant combined with budesonide for preventing bronchopulmonary dysplasia in very low birth weight infants]

OBJECTIVE

To explore the clinical efficacy of intratracheal instillation of pulmonary surfactant (PS) combined with budesonide for preventing bronchopulmonary dysplasia (BPD) in very low birth weight (VLBW) infants.

METHODS

Thirty VLBW infants with gestational age <32 weeks who developed neonatal respiratory distress syndrome (NRDS) (grade III-IV) suffering from intrauterine infection were randomly assigned into a PS + budesonide group and a PS alone group. The changes were compared between the two groups in arterial blood gas indexes, oxygenation index (OI), duration of mechanical ventilation, duration of oxygen supplementation, incidence of BPD, mortality rate at 36 weeks corrected gestational age and incidences of other complications except BPD.

RESULTS

Compared with the PS alone group, the PS+budesonide group had a lower incidence of BPD, shorter duration of mechanical ventilation and oxygen supplementation (P<0.05). On the 2nd to 6th day after treatment, the PS+budesonide group had higher pH value of arterial blood gas and OI and lower carbon dioxide partial pressure compared with the PS alone group (P<0.05). There were no significant differences in the mortality rate at 36 weeks corrected gestational age and the incidences of other complications except BPD between the two groups (P>0.05).

CONCLUSIONS

Intratracheal instillation of PS combined with budesonide can effectively reduce the incidence of BPD in VLBW premature infants with severe NRDS.

Early administration of inhaled corticosteroids for preventing chronic lung disease in very low birth weight preterm neonates

BACKGROUND

Chronic lung disease (CLD) remains a common complication among preterm infants. There is increasing evidence that inflammation plays an important role in the pathogenesis of CLD. Due to their strong anti-inflammatory properties, corticosteroids are an attractive intervention strategy. However, there are growing concerns regarding short- and long-term effects of systemic corticosteroids. Theoretically, administration of inhaled corticosteroids may allow for beneficial effects on the pulmonary system with a lower risk of undesirable systemic side effects.

OBJECTIVES

To determine the impact of inhaled corticosteroids administered to preterm infants with birth weight up to 1500 grams (VLBW) beginning in the first two weeks after birth for the prevention of CLD as reflected by the requirement for supplemental oxygen at 36 weeks' postmenstrual age (PMA).

SEARCH METHODS

Randomised and quasi-randomised trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 12) in the Cochrane Library (searched 5 January 2016), MEDLINE (1966 to 5 January 2016), Embase (1980 to 5 January 2016), CINAHL (1982 to 5 January 2016), reference lists of published trials and abstracts published in Pediatric Research or electronically on the Pediatric Academic Societies web-site (1990 to May 2016).

SELECTION CRITERIA

We included in this review randomised controlled trials of inhaled corticosteroid therapy initiated within the first two weeks of life in VLBW preterm infants.

DATA COLLECTION AND ANALYSIS

We evaluated data regarding clinical outcomes, including: CLD at 28 days or 36 weeks' PMA; mortality; combined outcome of death or CLD at 28 days of age and at 36 weeks' PMA; the need for systemic corticosteroids; failure to extubate within 14 days; and adverse effects of corticosteroids. All data were analysed using Review Manager (RevMan) 5. Meta-analyses were performed using relative risk (RR) and risk difference (RD), along with their 95% confidence intervals (CI). If RD was significant, the number needed to treat for an additional beneficial outcome (NNTB) was calculated. We used the GRADE approach to assess the quality of evidence.

MAIN RESULTS

According to GRADE the quality of the studies was moderate. Three additional trials are included in this update. The present review includes data analyses based on 10 qualifying trials that enrolled 1644 neonates. There was no significant difference in the incidence of CLD at 36 weeks' PMA in the inhaled steroid versus the placebo group (5 trials, 429 neonates) among all randomised (typical RR 0.97, 95% CI 0.62 to 1.52; typical RD -0.00, 95% CI -0.07 to 0.06). There was no heterogeneity for this outcome (typical RR I² = 11%; typical RD I² = 0%). There was a significant reduction in the incidence of CLD at 36 weeks' PMA among survivors (6 trials, 1088 neonates) (typical RR 0.76, 95% CI 0.63 to 0.93; typical RD -0.07, 95% CI -0.13 to -0.02; NNTB 14, 95% CI 8 to 50). There was a significant reduction in the combined outcome of death or CLD at 36 weeks' PMA among all randomised neonates (6 trials, 1285 neonates) (typical RR 0.86, 95% CI 0.75 to 0.99; typical RD -0.06, 95% CI -0.11 to -0.00) (P = 0.04); NNTB 17, 95% CI 9 to infinity). There was no significant heterogeneity for any of these analyses (I² = 0%). A lower rate of reintubation was noted in the inhaled steroid group compared with the control group in one study. There were no statistically significant differences in short-term complications between groups and no differences in adverse events at long-term follow-up reported. Long-term follow-up of infants enrolled in the study by Bassler 2015 is ongoing.

AUTHORS' CONCLUSIONS

Based on this updated review, there is increasing evidence from the trials reviewed that early administration of inhaled steroids to VLBW neonates is effective in reducing the incidence of death or CLD at 36 weeks' PMA among either all randomised infants or among survivors. Even though there is statistical significance, the clinical relevance is of question as the upper CI limit for the outcome of death or CLD at 36 weeks' PMA is infinity. The long-term follow-up results of the Bassler 2015 study may affect the conclusions of this review. Further studies are needed to identify the risk/benefit ratio of different delivery techniques and dosing schedules for the administration of these medications. Studies need to address both the short- and long-term benefits and adverse effects of inhaled steroids with particular attention to neurodevelopmental outcome.

Inhaled Corticosteroids for Bronchopulmonary Dysplasia: A Meta-analysis

CONTEXT

Bronchopulmonary dysplasia (BPD) in preterm infants remains a major health burden despite many therapeutic interventions. Inhaled corticosteroids (IC) may be a safe and effective therapy.

OBJECTIVE

To assess the safety and efficacy of IC for prevention or treatment of BPD or death in preterm infants.

DATA SOURCES

PubMed, the Cochrane Library, Embase, and CINAHL from their inception until November 2015 together with other relevant sources.

STUDY SELECTION

Randomized controlled trials of ICs versus placebo for either prevention or treatment of BPD.

DATA EXTRACTION

This meta-analysis used a random-effects model with assessment of quality of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system.

RESULTS

Thirty-eight trials were identified, and 16 met inclusion criteria. ICs were associated with a significant reduction in death or BPD at 36 weeks' postmenstrual age (risk ratio [RR] = 0.86, 95% confidence interval [CI] 0.75 to 0.99, I² = 0%, P = .03; 6 trials, n = 1285). BPD was significantly reduced (RR = 0.77, 95% CI 0.65 to 0.91, I² = 0%, 7 trials, n = 1168), although there was no effect on death (RR = 0.97, 95% CI 0.42 to 2.2, I² = 50%, 7 trials, n = 1270). No difference was found for death or BPD at 28 days' postnatal age. The use of systemic steroids was significantly reduced in treated infants (13 trials, n = 1537, RR = 0.87, 95% CI 0.76 to 0.98 I² = 3%,). No significant differences were found in neonatal morbidities and other adverse events.

LIMITATIONS

Long-term follow-up data are awaited from a recent large randomized controlled trial.

CONCLUSIONS

Very preterm infants appear to benefit from ICs with reduced risk for BPD and no effect on death, other morbidities, or adverse events. Data on long-term respiratory, growth, and developmental outcomes are eagerly awaited.

Early inhaled steroid use in extremely low birthweight infants: a randomised controlled trial

OBJECTIVE

We hypothesised that a prophylactic inhaled steroid would prevent the progression of bronchopulmonary dysplasia (BPD) in extremely low birthweight infants (ELBWIs).

DESIGN

This study was a multicentre, randomised, double-blinded, placebo-controlled trial.

SETTING

This investigation was conducted in 12 level III neonatal intensive care units (NICUs).

PATIENTS

A total of 211 ELBWIs requiring ventilator support were enrolled.

INTERVENTION

Starting within 24 h of birth and continuing until 6 weeks of age or extubation, two doses of 50 μg fluticasone propionate (FP) or placebo were administered every 24 h.

MAIN OUTCOME MEASUREMENT

The primary outcome measure used to indicate the morbidity of severe BPD incidence was death or oxygen dependence at discharge from the NICU. The secondary measures were neurodevelopmental impairments (NDIs) at 18 months of postmenstrual age and 3 years of age. We performed subgroup analyses based on gestational week (GW) and the presence of chorioamnionitis (CAM).

RESULTS

Infants were randomised into the FP (n=107) or placebo (n=104) groups. No significant differences were detected between the FP and placebo groups with respect to either the frequency of death or the oxygen dependence at discharge or NDIs. In subgroup analyses, the frequencies of death and oxygen dependence at discharge were significantly decreased in the FP group for infants born at 24-26 GWs and for infants with CAM, regardless of the GW at birth.

CONCLUSIONS

Inhaled steroids have no effect on the prevention of severe BPD or long-term NDI but might decrease the severity of BPD for ELBWIs with a risk factor.

TRIAL REGISTRATION NUMBER

UMIN-CTR C000000405.

Effects of antenatal glucocorticoids on the developing brain

Glucocorticoids (GCs) regulate distinct physiological processes in the developing fetus, in particular accelerating organ maturation that enables the fetus to survive outside the womb. In preterm birth, the developing fetus does not receive sufficient exposure to endogenous GCs in utero for proper organ development predisposing the neonate to complications including intraventricular hemorrhage, respiratory distress syndrome (RDS) and necrotizing enterocolitis (NEC). Synthetic GCs (sGCs) have proven useful in the prevention of these complications since they are able to promote the rapid maturation of underdeveloped organs present in the fetus. While these drugs have proven to be clinically effective in the prevention of IVH, RDS and NEC, they may also trigger adverse developmental side effects. This review will examine the current clinical use of antenatal sGC therapy in preterm birth, their placental metabolism, and their effects on the developing brain.

Lung Injury and Bronchopulmonary Dysplasia in Newborn Infants

Bronchopulmonary dysplasia is the most common morbidity among surviving premature infants. Injury to the developing lung is the result of the interaction between a susceptible host and a number of contributing factors such as mechanical ventilation and infection. The resulting persistent impairment of pulmonary function and need for ongoing therapy are the underlying characteristics of bronchopulmonary dysplasia. Important insights into the pathogenesis of bronchopulmonary dysplasia have led to numerous therapies and preventive approaches. Although significant progress has been made, in order to further affect the incidence and severity of the disease, we need to further study (a) the genetically determined predisposing factors, (b) the relative contribution of the various pathogenetic pathways, and, most important, (c) how to best translate the knowledge gained from these studies into effective clinical approaches.

Intratracheal Administration of Budesonide/Surfactant to Prevent Bronchopulmonary Dysplasia

RATIONALE

Bronchopulmonary dysplasia (BPD) is an important complication of mechanical ventilation in preterm infants, and no definite therapy can eliminate this complication. Pulmonary inflammation plays a crucial role in its pathogenesis, and glucocorticoid is one potential therapy to prevent BPD.

OBJECTIVES

To compare the effect of intratracheal administration of surfactant/budesonide with that of surfactant alone on the incidence of death or BPD.

METHODS

A clinical trial was conducted in three tertiary neonatal centers in the United States and Taiwan, in which 265 very-low-birth-weight infants with severe respiratory distress syndrome who required mechanical ventilation and inspired oxygen (fraction of inspired oxygen, ≥50%) within 4 hours of birth were randomly assigned to one of two groups (131 intervention and 134 control). The intervention infants received surfactant (100 mg/kg) and budesonide (0.25 mg/kg), and the control infants received surfactant only (100 mg/kg), until each infant required inspired O2 at less than 30% or was extubated.

MEASUREMENTS AND MAIN RESULTS

The intervention group had a significantly lower incidence of BPD or death (55 of 131 [42.0%] vs. 89 of 134 [66%]; risk ratio, 0.58; 95% confidence interval, 0.44-0.77; P < 0.001; number needed to treat, 4.1; 95% confidence interval, 2.8-7.8). The intervention group required significantly fewer doses of surfactant than did the control group. The intervention group had significantly lower interleukin levels (IL-1, IL-6, IL-8) in tracheal aspirates at 12 hours and lower IL-8 at 3-5 and 7-8 days.

CONCLUSIONS

In very-low-birth-weight infants with severe respiratory distress syndrome, intratracheal administration of surfactant/budesonide compared with surfactant alone significantly decreased the incidence of BPD or death without immediate adverse effect. Clinical trial registered with www.clinicaltrials.gov (NCT-00883532).

Systematic Review of Inhaled Bronchodilator and Corticosteroid Therapies in Infants with Bronchopulmonary Dysplasia: Implications and Future Directions

BACKGROUND

There is much debate surrounding the use of inhaled bronchodilators and corticosteroids for infants with bronchopulmonary dysplasia (BPD).

OBJECTIVE

The objective of this systematic review was to identify strengths and knowledge gaps in the literature regarding inhaled therapies in BPD and guide future research to improve long-termoutcomes.

METHODS

The databases of Academic Search Complete, CINAHL, PUBMED/MEDLINE, and Scopus were searched for studies that evaluated both acute and long-term clinical outcomes related to the delivery and therapeutic efficacy of inhaled beta-agonists, anticholinergics and corticosteroids in infants with developing and/or established BPD.

RESULTS

Of 181 articles, 22 met inclusion criteria for review. Five evaluated beta-agonist therapies (n = 84, weighted gestational age (GA) of 27.1(26-30) weeks, weighted birth weight (BW) of 974(843-1310) grams, weighted post menstrual age (PMA) of 34.8(28-39) weeks, and weighted age of 53(15-86) days old at the time of evaluation). Fourteen evaluated inhaled corticosteroids (n = 2383, GA 26.2(26-29) weeks, weighted BW of 853(760-1114) grams, weighted PMA of 27.0(26-31) weeks, and weighted age of 6(0-45) days old at time of evaluation). Three evaluated combination therapies (n = 198, weighted GA of 27.8(27-29) weeks, weighted BW of 1057(898-1247) grams, weighted PMA of 30.7(29-45) weeks, and age 20(10-111) days old at time of evaluation).

CONCLUSION

Whether inhaled bronchodilators and inhaled corticosteroids improve long-term outcomes in BPD remains unclear. Literature regarding these therapies mostly addresses evolving BPD. There appears to be heterogeneity in treatment responses, and may be related to varying modes of administration. Further research is needed to evaluate inhaled therapies in infants with severe BPD. Such investigations should focus on appropriate definitions of disease and subject selection, timing of therapies, and new drugs, devices and delivery methods as compared to traditional methods across all modalities of respiratory support, in addition to the assessment of long-term outcomes of initial responders.

Generating Charged Pharmaceutical Aerosols Intended to Improve Targeted Drug Delivery in Ventilated Infants

The delivery of pharmaceutical aerosols to infants receiving mechanical ventilation is extremely challenging due to small diameter flow passages, low tidal volumes, and frequent exhalation of the aerosol. The use of small charged particles is proposed as a novel method to prevent deposition in ventilator components and foster deposition in the lower infant airways. The objective of this study was to compare the performance of multiple new devices for generating small charged particles that are expected to maximize respiratory drug delivery in ventilated infants. Criteria used to select a leading device included production of a charged aerosol with a mass median aerodynamic diameter (MMAD) ≤ approximately 1.8 μm; low device depositional loss of the aerosol (<20%); particle charge in the range of the Rayleigh limit/100; and high drug output with low performance variability. Proposed new devices were a wick electrospray (WES) system with accelerated cross-flow air; a condensational vapor (CV) system with a charged solution and strong field gradient; and a low flow - induction charger (LF-IC) designed to operate with a modified commercial mesh nebulizer. Based on infant ventilation conditions, flow rates through the devices were in a range of 2-5 L/min and the devices were assessed in terms of depositional drug loss and emitted drug mass; droplet size distribution (DSD) using a Mini-MOUDI; and DSD and net charge with a modified ELPI. Considering the WES, primary limitations were (i) low and variable aerosol production rates and (ii) high device depositional losses. The CV device produced a high quality aerosol with a MMAD of 0.14 μm and a drug delivery rate of 25 μg/min. However, the device was excluded because it failed to produce a charged aerosol. In contrast, the LF-IC produced a 1.6 μm aerosol with high net charge, low device depositional loss (<15% based on recovery), and low variability. In the ELPI size fraction bin nearest the MMAD, the LF-IC produced >100 elementary charges per particle, which was an order of magnitude increase compared to the case of zero charging voltage. In conclusion, the LF-IC was selected as a leading system that is expected to improve aerosol delivery efficiency in ventilated infants through the use of small charged particles.

Optimal delivery of aerosols to infants during mechanical ventilation

PURPOSE

The objective of this study was to determine optimal aerosol delivery conditions for a full-term (3.6 kg) infant receiving invasive mechanical ventilation by evaluating the effects of aerosol particle size, a new wye connector, and timing of aerosol delivery.

METHODS

In vitro experiments used a vibrating mesh nebulizer and evaluated drug deposition fraction and emitted dose through ventilation circuits containing either a commercial (CM) or new streamlined (SL) wye connector and 3-mm endotracheal tube (ETT) for aerosols with mass median aerodynamic diameters of 880 nm, 1.78 μm, and 4.9 μm. The aerosol was released into the circuit either over the full inhalation cycle (T1 delivery) or over the first half of inhalation (T2 delivery). Validated computational fluid dynamics (CFD) simulations and whole-lung model predictions were used to assess lung deposition and exhaled dose during cyclic ventilation.

RESULTS

In vitro experiments at a steady-state tracheal flow rate of 5 L/min resulted in 80-90% transmission of the 880-nm and 1.78-μm aerosols from the ETT. Based on CFD simulations with cyclic ventilation, the SL wye design reduced depositional losses in the wye by a factor of approximately 2-4 and improved lung delivery efficiencies by a factor of approximately 2 compared with the CM device. Delivery of the aerosol over the first half of the inspiratory cycle (T2) reduced exhaled dose from the ventilation circuit by a factor of 4 compared with T1 delivery. Optimal lung deposition was achieved with the SL wye connector and T2 delivery, resulting in 45% and 60% lung deposition for optimal polydisperse (∼1.78 μm) and monodisperse (∼2.5 μm) particle sizes, respectively.

CONCLUSIONS

Optimization of selected factors and use of a new SL wye connector can substantially increase the lung delivery efficiency of medical aerosols to infants from current values of <1-10% to a range of 45-60%.

Utilization of inhaled corticosteroids for infants with bronchopulmonary dysplasia

OBJECTIVE

To determine demographic and clinical variables associated with inhaled corticosteroid administration and to evaluate between-hospital variation in inhaled steroid use for infants with bronchopulmonary dysplasia (BPD).

DESIGN

Retrospective Cohort Study.

SETTING

Neonatal units of 35 US children's hospitals; as recorded in the Pediatric Health Information System (PHIS) database.

PATIENTS

1429 infants with evolving BPD at 28 days who were born at <29 weeks gestation with birth weight <1500 grams, admitted within the first 7 postnatal days, and discharged between January 2007-June 2011.

RESULTS

Inhaled steroids were prescribed to 25% (n = 352) of the cohort with use steadily increasing during the first two months of hospitalization. The most frequently prescribed steroid was beclomethasone (n = 194, 14%), followed by budesonide (n = 125, 9%), and then fluticasone (n = 90, 6%). Birth gestation <24 weeks, birth weight 500-999 grams, and prolonged ventilation all increased the adjusted odds of ever receiving inhaled corticosteroids (p<0.05). Wide variations between hospitals in the frequency of infants ever receiving inhaled steroids (range: 0-60%) and the specific drug prescribed were noted. This variation persisted, even after controlling for observed confounders.

CONCLUSIONS

Inhaled corticosteroid administration to infants with BPD is common in neonatal units within U.S. Children's hospitals. However, its utilization varies markedly between centers from no treatment at some institutions to the majority of infants with BPD being treated at others. This supports the need for further research to identify the benefits and potential risks of inhaled steroid usage in infants with BPD.

A systematic review of randomized controlled trials for the prevention of bronchopulmonary dysplasia in infants

OBJECTIVE

Bronchopulmonary dysplasia (BPD) is the most common cause of pulmonary morbidity in premature infants and is associated with life-long morbidities. Developing drugs for the prevention of BPD would improve public health. We sought to determine characteristics of favorable randomized controlled trials (RCTs) of drugs for BPD prevention.

STUDY DESIGN

We searched MEDLINE and EMBASE from 1992 to 2014 using the MeSH terms 'BPD' and 'respiratory distress syndrome, newborn'. We included a Cochrane Library search to ensure inclusion of all available RCTs. We identified RCTs with BPD as a primary or secondary outcome and determined the definition of BPD used by the study. We determined whether a phase I or phase II study-to determine drug safety, efficacy or optimal dose-was performed before the RCT. Finally, we searched the Cochrane Library for meta-analyses for each drug and used the results of available meta-analyses to define a favorable versus unfavorable RCT.

RESULT

We identified 2026 articles; 47 RCTs met our inclusion criteria encompassing 21 drugs; 5 of the drugs reduced the incidence of BPD. We found data from phase I or II studies for 16 of the drugs, but only 1 demonstrated a reduction of BPD.

CONCLUSION

The majority of the drugs studied in RCTs failed to reduce the incidence of BPD. Performing early-phase studies before phase III trials might provide necessary information on drugs and drug doses capable of preventing BPD, thus informing the development of future RCTs.

Early administration of inhaled corticosteroids for preventing chronic lung disease in ventilated very low birth weight preterm neonates

BACKGROUND

Chronic lung disease remains a common complication among preterm infants. There is increasing evidence that inflammation plays an important role in the pathogenesis of CLD. Due to their strong anti-inflammatory properties, corticosteroids are an attractive intervention strategy. However, there are growing concerns regarding short and long-term effects of systemic corticosteroids. Theoretically, administration of inhaled corticosteroids may allow for beneficial effects on the pulmonary system with a lower risk of undesirable systemic side effects.

OBJECTIVES

To determine the impact of inhaled corticosteroids administered to ventilated very low birth weight preterm neonates in the first two weeks of life for the prevention of chronic lung disease (CLD).

SEARCH METHODS

Randomised and quasi-randomised trials were identified by searching the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 3, 2007), MEDLINE (1966 to July 2007), EMBASE (1980 to July 2007), CINAHL (1982 to July 2007), reference lists of published trials and abstracts published in Pediatric Research or electronically on the Pediatric Academic Societies web-site (1990 to April 2007).This search was updated in 2011.

SELECTION CRITERIA

Randomised controlled trials of inhaled corticosteroid therapy initiated within the first two weeks of life in ventilated preterm infants with birth weight <1500 grams were included in this review.

DATA COLLECTION AND ANALYSIS

Data regarding clinical outcomes including chronic lung disease at 28 days or 36 weeks postmenstrual age (PMA), mortality, combined outcome of death or CLD at 28 days of age and at 36 weeks PMA, the need for systemic corticosteroids, failure to extubate within 14 days and adverse effects of corticosteroids were evaluated. All data were analysed using RevMan 4.2.10. When possible, meta-analysis was performed using relative risk (RR), risk difference (RD), along with their 95% confidence intervals (CI). If RD was significant, the number needed to treat (NNT) was calculated.

MAIN RESULTS

One ongoing trial was identified for inclusion in this update. Eleven trials assessing the impact of inhaled corticosteroid for the prevention of CLD were identified. Four trials were excluded. The present review includes data analyses based on seven qualifying trials. There was no statistically significant effect of inhaled steroids on CLD either at 28 days [typical RR 1.05 (95% CI 0.84 to 1.32); typical RD 0.02 (95% CO -0.07 to 0.11)] or at 36 weeks PMA [typical RR 0.97 (95% CI 0.62 to 1.52); typical RD 0.00 (95% CI -0.07, 0.06)], when analysed either for all randomised infants or among survivors. No statistically significant differences were noted for mortality or for the combined outcome of mortality and CLD either at 28 days of age or at 36 weeks PMA. There were no statistically significant differences in adverse events between groups.

AUTHORS' CONCLUSIONS

Based on this updated review, there is no evidence from the trials reviewed that early administration (in the first two weeks of life) of inhaled steroids to ventilated preterm neonates was effective in reducing the incidence of CLD. Currently, use of inhaled steroids in this population cannot be recommended. Studies are needed to identify the risk/benefit ratio of different delivery techniques and dosing schedules for the administration of these medications. Studies need to address both the short-term and long-term benefits and adverse effects of inhaled steroids with particular attention to neurodevelopmental outcome.

Late (≥ 7 days) inhalation corticosteroids to reduce bronchopulmonary dysplasia in preterm infants

BACKGROUND

Bronchopulmonary dysplasia (BPD), defined as oxygen dependence at 36 weeks postmenstrual age (PMA), remains an important complication of prematurity. Pulmonary inflammation plays a central role in the pathogenesis of BPD. Attenuating pulmonary inflammation with postnatal systemic corticosteroids reduces the incidence of BPD in preterm infants but may be associated with an increased risk of adverse neurodevelopmental outcomes. Local administration of corticosteroids via inhalation might be an effective and safe alternative.

OBJECTIVES

To determine if administration of inhalation corticosteroids after the first week of life to preterm infants at high risk of developing BPD is effective and safe in reducing the incidence of death and BPD as separate or combined outcomes.

SEARCH METHODS

We identified randomised, controlled trials by searching the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library), PubMed (from 1966), EMBASE (from 1974), CINAHL (from 1982), references from retrieved trials and handsearches of journals, all assessed to February 2012.

SELECTION CRITERIA

Randomised controlled trials comparing inhalation corticosteroids, started ≥ 7 days postnatal age (PNA) but before 36 weeks PMA, to placebo in ventilated and non-ventilated infants at risk of BPD were included. Trials investigating systemic corticosteroids versus inhalation corticosteroids were excluded.

DATA COLLECTION AND ANALYSIS

Data on patient characteristics, trial methodology, and inhalation regimens were collected. The primary outcomes were death or BPD, or both, at 28 days PNA or 36 weeks PMA. Secondary outcomes were short-term respiratory outcomes, such as failure to extubate, total days of mechanical ventilation and oxygen use, and the need for systemic corticosteroids. The original trialists were contacted to verify the validity of extracted data and to provide missing data. All data were analysed using RevMan 5.0.24. When possible, meta-analysis was performed using typical risk ratio (TRR) for dichotomous outcomes and weighted mean difference (WMD) for continuous outcomes along with their 95% confidence intervals (CI). Ventilated and non-ventilated participants were analysed separately.

MAIN RESULTS

Eight trials randomising 232 preterm infants were included in this review. Inhalation corticosteroids did not reduce the separate or combined outcomes of death or BPD. Furthermore, inhalation steroids did not impact short-term respiratory outcomes such as failure to extubate and total duration of mechanical ventilation or oxygen dependency. There was a trend to a reduced use of systemic corticosteroids in favour of inhalation corticosteroids (TRR 0.51; 95% CI 0.26 to 1.00). There was a paucity of data on short-term and long-term adverse effects. These results should be interpreted with caution because the total number of randomised patients is relatively small and most trials differed considerably in patient characteristics, inhalation therapy and outcome definitions.

AUTHORS' CONCLUSIONS

Based on the results of the currently available evidence, inhalation corticosteroids initiated at ≥ 7 days of life for preterm infants at high risk of developing BPD cannot be recommended at this point in time. More and larger randomised, placebo-controlled trials are needed to establish the efficacy and safety of inhalation corticosteroids.

Differential effects of cholesterol and budesonide on biophysical properties of clinical surfactant

INTRODUCTION

Corticosteroids have been widely used in clinical medicine as a first-line therapy to modify the inflammatory response in many pulmonary and systemic diseases. Inhaled and intratracheally administered corticosteroids have a particular interest in that their use allows the clinician to circumvent systemic steroid side effects. However, it is vital that corticosteroids delivered via the lungs not interfere with surface activity of the pulmonary surfactant lining layer.

RESULTS

We found differential effects of cholesterol and budesonide on the biophysical properties of a cholesterol-free clinical surfactant preparation, Curosurf. At a low concentration up to 1%, both steroids play a similar role of fluidizing the surfactant film. However, when steroid concentration is increased to 10%, cholesterol induces a unique phase transition that abolishes the surface activity of the Curosurf film. By contrast, 10% budesonide simply fluidizes the film, thus having only limited effects on surface activity.

DISCUSSION

Together with those of a previous study using a cholesterol-containing surfactant, our findings suggest that cholesterol-free surfactant preparations may be more advantageous than cholesterol-containing preparations as a carrier of budesonide because a larger amount of the drug may be delivered to the lungs without significantly compromising the surface activity of pulmonary surfactant.

METHODS

Langmuir balance was used to study the effect of cholesterol and budesonide added at different concentrations on surface activity of Curosurf. Atomic force microscopy (AFM) was used to reveal their effects on the interfacial molecular organization and lateral structure of Curosurf films.

Biophysical interaction between corticosteroids and natural surfactant preparation: implications for pulmonary drug delivery using surfactant a a carrier

Intratracheal administration of corticosteroids using a natural pulmonary surfactant as a delivery vehicle has recently received significant attention in hopes of treating premature newborns with or at high risk for chronic lung disease. As a new practice, both the surfactant preparation used as the carrier and the corticosteroid delivered as the anti-inflammatory agent, and their mixing ratios, have not been standardized and optimized. Given the concern that corticosteroids delivered via a pulmonary surfactant may compromise its surface activity and thus worsen lung mechanics, the present study was carried out to characterize the biophysical interaction between a natural surfactant preparation, Infasurf, and two commonly used inhaled corticosteroids, budesonide and beclomethasone dipropionate (BDP). Based on surface activity measurements by the Langmuir balance and lateral film structure studied by atomic force microscopy, our findings suggest that when Infasurf is used as a carrier, a budesonide concentration less than 1 wt% of surfactant or a BDP concentration up to 10 wt % should not significantly affect the biophysical properties of Infasurf, thus being feasible for pulmonary delivery. Increasing corticosteroid concentration beyond this range leads to early collapse of the surfactant film due to increased film fluidization. Our study further suggests that different affinities to the surfactant films are responsible for the different behavior of budesonide and BDP. In addition to the translational value in treating chronic lung disease, this study may also have implications in inhaled steroid therapy to treat asthma.

Postnatal corticosteroids for prevention and treatment of chronic lung disease in the preterm newborn

Despite significant progress in the treatment of preterm neonates, bronchopulmonary dysplasia (BPD) continues to be a major cause of neonatal morbidity. Affected infants suffered from long-term pulmonary and nonpulmonary sequel. The pulmonary sequels include reactive airway disease and asthma during childhood and adolescence. Nonpulmonary sequels include poor coordination and muscle tone, difficulty in walking, vision and hearing problems, delayed cognitive development, and poor academic achievement. As inflammation seems to be a primary mediator of injury in pathogenesis of BPD, role of steroids as antiinflammatory agent has been extensively studied and proven to be efficacious in management. However, evidence is insufficient to make a recommendation regarding other glucocorticoid doses and preparations. Numerous studies have been performed to investigate the effects of steroid. The purpose of this paper is to evaluate these studies in order to elucidate the beneficial and harmful effects of steroid on the prevention and treatment of BPD.

Early prophylactic inhaled beclomethasone in infants less than 1250 g for the prevention of chronic lung disease

OBJECTIVE

Inflammation plays an important role in the development of chronic lung disease (CLD), which has become a major cause of morbidity in surviving infants less than 1250 g at birth. The authors hypothesized that the progression of this inflammation and, therefore, the establishment of CLD would be decreased with the use of early prophylactic inhaled corticosteroids. Short, and long term respiratory and neurodevelopmental outcomes were also examined.

DESIGN

A double-blind, randomized placebo controlled trial.

SETTING

Level-III neonatal intensive care unit.

POPULATION STUDIED

Sixty infants less than 1250 g at birth, diagnosed with respiratory distress syndrome and requiring ventilatory support at 72 h of age were enrolled in the study.

INTERVENTION

Infants enrolled received either placebo or beclomethasone diproprionate by a metered dose inhaler, which was used in-line with the ventilator circuit while the infant was ventilated and then via a spacer until 28 days of age.

RESULTS

Thirty infants were given beclomethasone and 30 were given placebo. There were two deaths in each group. Among the surviving infants, the frequency of moderate-to-severe CLD was 17% in each study group. Mean time to extubation was not different for beclomethasone compared with placebo at 16.4 and 12.5 days (P=0.12), respectively. The requirement for intravenous corticosteroids was lower in the beclomethasone-treated group (RR 0.67, 95% CI 0.43 to 1.04), although this difference was not statistically significant. The incidence of growth failure, infection and intraventricular hemmorhage did not differ between the two groups. Long term outcomes were not different with respect to the incidence of respiratory re-admissions, cerebral palsy, developmental delay, blindness or deafness.

CONCLUSIONS

Early treatment with inhaled beclomethasone diproprionate did not reduce the incidence of CLD or decrease the duration of mechanical ventilation. The decrease in intravenous corticosteroid use was not statistically significant. Long term outcome was not affected.

Pathogenesis and treatment of bronchopulmonary dysplasia

PURPOSE OF REVIEW

Bronchopulmonary dysplasia (BPD) is a chronic lung disease of infancy affecting mostly premature infants with significant morbidity and mortality. Improved survival of very immature infants has led to increased numbers of infants with this disorder. Acute and chronic lung injury and impaired postnatal lung growth are thought to be responsible for the development of BPD. Whereas changes in clinical practice have improved the clinical course and outcomes for infants with BPD, over the past decade, the overall incidence of BPD has not changed. This review will describe the prenatal and postnatal factors that contribute to the pathogenesis of BPD as well as current and experimental therapies for treatment of BPD.

RECENT FINDINGS

The factors that contribute to the pathogenesis of BPD are well described; however, recent studies have better defined how these factors modulate lung growth. Inflammation, proinflammatory cytokines and altered angiogenic gene signaling contribute to lung injury and impair prenatal and postnatal lung growth resulting in BPD; however, to date no therapy has been identified that potently and consistently prevents or reverses their effects on lung growth. We will discuss the cell signaling pathways affected in BPD and current therapies available for modulating these pathways.

SUMMARY

Despite current advances in neonatal care, BPD remains a heavy burden on healthcare resources. New treatments directed at either reducing lung injury or improving lung growth are under study.

A follow-up study of preterm infants given budesonide using surfactant as a vehicle to prevent chronic lung disease in preterm infants

OBJECTIVE

Our study of early intratracheal instillation of budesonide using surfactant as vehicle showed a significant decrease in death or chronic lung disease (CLD) in preterm infants with severe respiratory distress syndrome (RDS). We now report the long-term outcome at about 2 to 3 years of age.

STUDY DESIGN

Of the 75 potential survivors, 67 (90%) were studied (35 budesonide-treated, 32 control). All infants had birth weight <1500 g and had severe RDS requiring intermittent mechanical ventilation shortly after birth. The treated group received a mixture of budesonide and surfactant every 8 hours. The control group received only surfactant.

RESULTS

The physical growth and the neurological examinations were comparable between the groups at follow-up. Infants in the group treated with budesonide tended to have higher PDI and MDI scores than infants in the control group (79 +/- 20 vs 74 +/- 18 and 80 +/- 19 vs 75 +/- 20), but these differences were not statistically significant. The incidence of neurodevelopmental impairment was 11 (31%) in the treated group and 13 (40%) in the control group (P = .367).

CONCLUSIONS

Early intratracheal instillation of budesonide using surfactant as a vehicle significantly improved pulmonary outcome without causing long-term adverse effects.

Quality improvement in respiratory care: decreasing bronchopulmonary dysplasia

Chronic lung disease (CLD) is one of the most common long-term complications in very preterm infants. Bronchopulmonary dysplasia (BPD) is the most common cause of CLD in infancy. Modern neonatal respiratory care has witnessed the emergence of a new BPD that exhibits decreased fibrosis and emphysema, but also decreased alveolar septation, and microvascular development. CLD encompasses the classic and the new BPD, and recognizes that lung injury can occur in term infants who need aggressive ventilatory support and who develop lung injury as a result, and that CLD is a multisystem disease. Controversy exists on whether quality improvement (QI) methods that implement multiple interventions will be effective in limiting pathology with multiple causes. Caution in generalization of QI findings is encouraged. QI methods toward improvement in CLD or any other outcome should be considered as a tool for implementing evidence and studying the effects of change in complex adaptive systems.

Postnatal corticosteroids for bronchopulmonary dysplasia

Corticosteroids are used to improve lung function in infants who are progressing toward bronchopulmonary dysplasia. Corticosteroids facilitate extubation, but there is conflicting information about adverse effects on the developing brain. An approach to minimizing risk is to use low-dose, short-duration treatments in the highest risk ventilator-dependent patients. Questions remain about which corticosteroid is the safest and how to dose that corticosteroid.

Adjunctive pharmacotherapy in neonates with respiratory failure

Whereas oxygen, continuous positive airway pressure (CPAP) and mechanical ventilation are the mainstays of treatment of pulmonary conditions in newborns, there are a number of adjunctive therapies that may improve the pulmonary function of these infants. These include the use of bronchodilators and diuretics given either systemically or through the inhaled route, mucolytic agents, and anti-inflammatory agents. This chapter gives an overview of the use of the most-studied agents including aerosolized bronchodilators, systemic and inhaled diuretics, and systemic and inhaled corticosteroids in the treatment and prevention of, where appropriate, respiratory distress syndrome, bronchopulmonary dysplasia, and meconium aspiration syndrome. Evidence on the use of mucolytic agents including acetylcysteine and deoxyribonuclease, and the anti-inflammatory agents including the macrolide antibiotics, cromolyn, pentoxyfylline, and recombinant human Clara cell protein are also reviewed.

Inhaled corticosteroid therapy reduces cytokine levels in sputum from very preterm infants with chronic lung disease

AIM

To evaluate the effects of inhaled corticosteroid therapy and high-frequency oscillatory ventilation (oscillation) on preterm infants with chronic lung disease (CLD).

METHODS

Ten infants with CLD who received inhaled corticosteroid therapy were enrolled. Week 1 was defined as the first week of therapy. The concentrations of interleukin (IL)-8, tumour necrosis factor-alpha (TNF-alpha), IL-1beta, IL-6, IL-10 and IL-12p70 in serial sputum specimens from the infants were determined using a cytometric bead array.

RESULTS

The sputum concentrations of IL-8 obtained from the infants during week 3-4 were significantly lower than those obtained before therapy and during week 1-2. The sputum concentrations of TNF-alpha, IL-6 and IL-10 during week 3-4 were significantly lower than the concentrations during week 1-2. The ratio of IL-8 levels during week 1-2 to those before therapy in infants who received oscillation (n = 4) was significantly lower than in those who received intermittent mandatory ventilation (n = 6).

CONCLUSION

Inhaled corticosteroids may be associated with a decrease in pro-inflammatory cytokine levels in sputum from infants with CLD from 2 weeks after the start of therapy. Our further investigations suggest that therapy with oscillation modulated airway inflammation earlier than therapy with intermittent mandatory ventilation.

Inflammatory mediators in the immunobiology of bronchopulmonary dysplasia

Inflammation is important in the development of bronchopulmonary dysplasia (BPD). Polymorphonuclear cells and macrophages and proinflammatory cytokines/chemokines denote early inflammation in clinical scenarios such as in utero inflammation with chorioamnionitis or initial lung injury associated with respiratory distress syndrome or ventilator-induced lung injury. The persistence and non-resolution of lung inflammation contributes greatly to BPD, including altering the lung's ability to repair, contributing to fibrosis, and inhibiting secondary septation, alveolarization, and normal vascular development. Further understanding of the role of inflammation in the pathogenesis of BPD, in particular, during the chronic inflammatory period, offers us the opportunity to develop inflammation-related prevention and treatment strategies of this disease that has long-standing consequences for very premature infants.

Early intratracheal instillation of budesonide using surfactant as a vehicle to prevent chronic lung disease in preterm infants: a pilot study

OBJECTIVE

Budesonide is an inhaled steroid with a strong topical effect but with minimal systemic effects; it has been effectively delivered to animal lungs using surfactant as a vehicle. The purposes of this study were to determine whether early intratracheal instillation of budesonide using surfactant as a vehicle would improve pulmonary status, reduce mortality, and reduce chronic lung disease morbidity.

PATIENTS AND METHODS

We conducted a prospective, randomized blind trial in 116 very low birth weight infants (< 1500 g) who had severe radiographic respiratory distress syndrome and required mechanical ventilation with fraction of inspired oxygen > or = 0.6 shortly after birth: 60 were in the treated group (intratracheal instillation of a mixture of 0.25 mg/kg of budesonide and 100.00 mg/kg of survanta, every 8 hours) and 56 were in the control group (100 mg/kg of survanta only, every 8 hours). The end point assessment was the number of infants who would die or develop chronic lung disease at 36 weeks' postconceptional age.

RESULTS

Infants in the treatment group required significantly lower mean airway pressure on day 1 and day 3 and had significantly lower oxygen index and PCO(2) during the first 3 days than infants in the control group. More infants were extubated in the treatment group than controls at 1 and 2 weeks. The combined outcome of deaths or chronic lung disease was significantly lower in the treatment group than in the control group (19 of 60 vs 34 of 56). No clinically significant adverse effects were observed during the study.

CONCLUSIONS

This pilot study indicated that early postnatal intratracheal instillation of budesonide using surfactant as vehicle significantly improved the combined outcome of death or chronic lung disease in small premature infants without causing immediate adverse effects. The results are encouraging, and a large sample multicenter trial is warranted.