Pulmonary function and bronchopulmonary dysplasia classification: insights from the Spanish Registry.

In 2016, the Spanish Research Group on Bronchopulmonary Dysplasia (BPD) (GEIDIS) established a national registry with participation of 66 hospitals to collect information on clinical characteristics and long-term outcomes of BPD infants into adulthood. The aim of this observational study is to examine forced spirometry data in early childhood and to assess their correlation with the respiratory support required at 36 weeks postmenstrual age (PMA). The study analyzed data from preterm infants with BPD born between January 2016 and December 2017 who underwent forced spirometry at 5-7 years of age. Statistical analyses were conducted to investigate the relationships between spirometry results, perinatal factors, and the required respiratory support at 36 weeks PMA. The study involved 143 patients with a median gestational age (GA) of 27.3 weeks (range 25.7-28.7) and a median weight of 880 g (range 740-1135). Abnormal spirometry results were observed in 39.2% (56) of the patients. Among patients diagnosed with BPD type 3, those requiring over 30% oxygen at 36 weeks PMA exhibited an increased risk of abnormal spirometry results (OR 4.48; 95% CI 1.11-18.13) compared to those requiring positive pressure with less than 30% oxygen. In addition, this subgroup had a higher risk of developing a restrictive-mixed pattern compared to those with BPD type 1 (OR 10.65; 95% CI 2.06-54.98) and BPD type 2 (OR 6.76; 95% CI 1.09-42.06). No significant differences were found in the incidence of an obstructive pattern between BPD types.      Conclusion: The requirement of more than 30% oxygen at 36 weeks PMA serves as a risk indicator for pulmonary function impairment in school-aged children with BPD. These findings suggest persistent airway and parenchymal injury in this specific patient population, and highlight the importance of careful monitoring to evaluate their long-term effects on lung function. What is Known: • Premature patients with bronchopulmonary dysplasia (BPD) may present abnormalities in pulmonary function tests during school age. However, the predictive accuracy of consensus BPD severity classification remains uncertain. What is New: • The requirement of more than 30% oxygen at 36 weeks postmenstrual age (PMA) indicates a potential risk of pulmonary function impairment in school-aged children with BPD. Additionally, a significant correlation has been observed between a restrictive-mixed pattern with exposure to mechanical ventilation and the development of severe forms of BPD.

Definitions of Bronchopulmonary Dysplasia: Which One Should We Use?

OBJECTIVE: To assess the clinical applicability of the current definitions of bronchopulmonary dysplasia (BPD) and their ability to predict subsequent respiratory outcomes. STUDY DESIGN: In this retrospective cohort study, data were collected from 104 preterm infants (mean gestational age, 25.8 weeks) diagnosed with BPD between 2010 and 2018 at a single tertiary care center. The infants were classified according to the following definitions: 2001 National Institute of Child Health and Human Development (NICHD), 2017 Canadian Neonatal Network (CNN), 2018 NICHD, and 2019 Neonatal Research Network (NRN). Logistic regression and the area under the receiver operating characteristic curve (AUC) were used to assess the predictive ability of each definition on mortality or severe respiratory morbidity at 18-24 months of age. RESULTS: All patients could be adequately classified by each definition, except for the 2001 NICHD definition, in which 11.4% were unclassifiable. The prevalence of BPD was 49% by the 2017 CNN definition and 70% by the 2018 NICHD and 2019 NRN definitions. The best regression model was the one that included the 2018 NICHD definition, which had an accuracy of 85.6% and a significantly higher AUC compared with the 2001 NICHD (0.891 vs 0.824; P = .015) and 2017 CNN (0.891 vs 0.811; P = .036) definitions, but not compared with the 2019 NRN definition (0.891 vs 0.833; P = .09). CONCLUSIONS: The current definitions of BPD showed a good predictive ability for mid-term respiratory outcomes, with the highest ability for the 2018 NICHD definition. Further studies are needed to establish the most appropriate definition of BPD.

Risk factors and bronchopulmonary dysplasia severity: data from the Spanish Bronchopulmonary Dysplasia Research Network.

GEIDIS is a national-based research-net registry of patients with bronchopulmonary dysplasia (BPD) from public and private Spanish hospitals. It was created to provide data on the clinical characterization and follow-up of infants with BPD until adulthood. The purpose of this observational study was to analyze the characteristics and the impact of perinatal risk factors on BPD severity. The study included 1755 preterm patients diagnosed with BPD. Of the total sample, 90.6% (n = 1591) were less than 30 weeks of gestation. The median gestational age was 27.1 weeks (25.8-28.5) and median birth weight 885 g (740-1,070 g). A total of 52.5% (n = 922) were classified as mild (type 1), 25.3% (n = 444) were moderate (type 2), and 22.2% (n = 389) were severe BPD (type 3). In patients born at under 30 weeks' gestation, most pre-and postnatal risk factors for type 2/3 BPD were associated with the length of exposure to mechanical ventilation (MV). Independent prenatal risk factors were male gender, oligohydramnios, and intrauterine growth restriction. Postnatal risk factors included the need for FiO2 of > 0.30 in the delivery room, nosocomial pneumonia, and the length of exposure to MV. Conclusion: In this national-based research-net registry of BPD patients, the length of MV is the most important risk factor associated with type 2/3 BPD. Among type 3 BPD patients, those who required an FiO2 > .30 at 36 weeks' postmenstrual age had a higher morbidity, during hospitalization and at discharge, compared to those with nasal positive pressure but FiO2 < .30. What is Known: • BPD is a highly complex multifactorial disease associated with preterm birth. What is New: • The length of exposure to mechanical ventilation is the most important postnatal risk factor associated to bronchopulmonary severity which modulate the effect of most pre and postnatal risk factors. • Among patients with BPD, the requirement for FiO2 >.30% at 36 weeks of postmenstrual age is associated with greater morbidity during hospitalization and at discharge.

Cryotherapy in the paediatric airway: Indications, success and safety.

BACKGROUND AND OBJECTIVE: Cryotherapy in interventional bronchoscopy is a new treatment modality, which has recently been made available for the paediatric airway. Lack of experience and safety concerns have led to hesitant adaptation. The aim of this study was to assess indications, success rates and complications of airway cryotherapy in children. METHODS: Bronchoscopists from medical centre performing cryotherapy in patients between 0 and 18 years were invited to participate in a prospective study based on an online questionnaire. Patient and participant data were collected between June 2020 and June 2021. RESULTS: A total of 69 cryotherapy procedures were performed in 57 patients a for three main indications: Biopsy (30), restoration of airway patency (23) and foreign body aspiration (16). The overall success rate was 93%, the remaining 7% were performed for foreign body removal and required a switch of technique. Restoration of airway patency was successfully applied in various pathologies, including mucus plugs, bronchial casts and post traumatic stenosis. The diagnostic yield of transbronchial biopsies was 96%. No severe complications were encountered; one pneumothorax following a cryobiopsy required a chest drain for 48 h. No child was admitted to intensive care or died from a procedural complication. CONCLUSION: In this largest paediatric case collection to date, cryotherapy was safe and carried a high success rate. Cryobiopsy compares favourably to the widely used forceps biopsy and could replace it in the future. Paediatric bronchoscopists are encouraged to add cryotherapy to their armamentarium of airway interventions.

Neutralizing antibodies after nebulized phage therapy in cystic fibrosis patients.

BACKGROUND: Cystic fibrosis (CF) patients are prone to recurrent multi-drug-resistant (MDR) bacterial lung infections. Under this scenario, phage therapy has been proposed as a promising tool. However, the limited number of reported cases hampers the understanding of clinical outcomes. Anti-phage immune responses have often been overlooked and only described following invasive routes of administration. METHODS: Three monophage treatments against Staphylococcus aureus and/or Pseudomonas aeruginosa lung infections were conducted in cystic fibrosis patients. In-house phage preparations were nebulized over 10 days with standard-of-care antibiotics. Clinical indicators, bacterial counts, phage and antibiotic susceptibility, phage detection, and immune responses were monitored. FINDINGS: Bacterial load was reduced by 3-6 log in two of the treatments. No adverse events were described. Phages remained in sputum up to 33 days after completion of the treatment. In all cases, phage-neutralizing antibodies were detected in serum from 10 to 42 days post treatment, with this being the first report of anti-phage antibodies after nebulized therapy. CONCLUSIONS: Nebulized phage therapy reduced bacterial load, improving quality of life even without bacterial eradication. The emergence of antibodies emphasizes the importance of long-term monitoring to better understand clinical outcomes. These findings encourage the use of personalized monophage therapies in contrast to ready-to-use cocktails, which might induce undesirable antibody generation. FUNDING: This study was supported by the Spanish Ministry of Science, Innovation and Universities; Generalitat Valenciana; and a crowdfunding in collaboration with the Spanish Cystic Fibrosis Foundation.

Respiratory outcomes of "new" bronchopulmonary dysplasia in adolescents: A multicenter study.

OBJECTIVE: Long-term respiratory consequences of bronchopulmonary dysplasia (BPD) in preterm infants born in the post-surfactant era ("new" BPD) remain partially unknown. The present study aimed to evaluate the respiratory outcomes of "new" BPD in adolescents who were born preterm. METHODS: This multicenter, cross-sectional study included 286 adolescents born between 2003 and 2005 (mean age: 14.2 years); among them, 184 and 102 were born extremely preterm (EP; <28 weeks' gestation) and moderate-late preterm (32 to <37 weeks' gestation), respectively. Among EP adolescents, 92 had BPD, and 92 did not. All participants underwent lung function tests, skin prick testing, and questionnaires on asthma symptoms and quality of life. RESULTS: EP adolescents with BPD had significantly lower forced expiratory volume in 1 s (FEV1 ), forced vital capacity (FVC), FEV1 /FVC ratio, and forced expiratory flow between 25% and 75% of FVC than other included adolescents. FEV1 /FVC ratios were below the lower limit of normal (z-score <-1.645) in 30.4% of EP adolescents with BPD, 13.0% of EP adolescents without BPD, and 11.8% of adolescents who were born moderate-late preterm. Bronchodilator response and air-trapping were significantly higher in BPD adolescents than in other adolescents. Diffusion capacity was significantly lower in EP adolescents than in moderate-late preterm adolescents. Asthma symptoms and quality-of-life scores were similar among groups. CONCLUSION: EP adolescents with "new" BPD had poorer pulmonary function than EP adolescents without BPD or moderate-late preterm adolescents. Further studies are needed to determine whether "new" BPD is associated with early-onset chronic obstructive pulmonary disease in adulthood.