Related Experiment Videos
Lung function outcome in children of premature birth
1University Department of Paediatrics/Department of Pulmonary Medicine, Women's & Children's Hospital, Adelaide, Australia. dkennedy@medicine.adelaide.edu.au
Insights
Improved survival for premature infants has increased bronchopulmonary dysplasia (BPD) cases. While early air trapping resolves, small airway obstruction persists, impacting lung growth and function long-term.
Area of Science:
- Neonatal Medicine
- Pediatric Pulmonology
- Respiratory Physiology
Background:
- Improved survival rates for premature infants (<1500g) since the 1960s have led to increased prevalence of bronchopulmonary dysplasia (BPD) and chronic lung disease (CLD).
- While initial air trapping in BPD often improves by age 3-4, persistent small airway obstruction suggests dysanaptic lung growth.
- Long-term respiratory implications for premature infants, even without severe BPD, remain unclear.
Purpose of the Study:
- To review the long-term respiratory outcomes in children with BPD/CLD.
- To explore factors influencing lung function and airway responsiveness in this population.
- To highlight the need for strategies to reduce premature birth rates.
Main Methods:
- Review of existing literature on BPD, CLD, and long-term respiratory outcomes in premature infants.
- Analysis of associations between lung function decrements, neonatal interventions, and perinatal factors.
- Examination of bronchial hyper-responsiveness in relation to prematurity and BPD.
Main Results:
- The majority of older children and adolescents with BPD/CLD have minimal respiratory symptoms, despite slow improvement in small airway obstruction.
- Reduced expiratory flows in premature infants are linked to neonatal oxygen therapy and ventilation, but strongly associated with birthweight, suggesting intrauterine factors.
- Bronchial hyper-responsiveness is elevated in children with BPD and to a lesser extent in other preterm infants.
Conclusions:
- Dysanaptic lung growth may occur in BPD, with slow improvement in small airway obstruction.
- Birthweight and potential intrauterine factors appear more critical than perinatal events for long-term airway function.
- Further longitudinal studies are needed to understand adolescent and adult lung function tracking, and the causes of bronchial hyper-responsiveness.
Abstract:
Since the 1960s there has been a continual improvement in the survival of premature infants of birthweight less than 1500 g. This has resulted in an increase in the prevalence of bronchopulmonary dysplasia (BPD), or its milder form, chronic lung disease (CLD) of prematurity. In children with BPD; the initial air trapping improves in the first 3-4 years of life, but small airway obstruction is often slow to improve, suggesting dysanaptic lung growth. Despite this, the majority of older children and adolescents with BPD/CLD do not have significant respiratory symptoms. Children born prematurely with or without hyaline membrane disease may also have a reduction in expiratory flows during childhood, albeit less severe. The clinical significance of this in the longer term is unclear. Although significant associations between decrements in expiratory flows, neonatal oxygen therapy and assisted ventilation have been demonstrated. Airway function has also been reported to be largely unrelated with perinatal events but strongly associated with birthweight. The latter suggests that intra-uterine factors such as under-nutrition may be more important than hitherto recognized. Because of a lack of longitudinal studies, it is unclear how lung function will track during adolescence and adult life. Bronchial hyper-responsiveness is significantly increased in children with BPD and to a lesser extent in those born prematurely with or without hyaline membrane disease. It is unclear whether this is due to a genetic predisposition, neonatal lung injury or anatomically smaller airways. Given the morbidity and fiscal cost of a premature birth, effective strategies to reduce the premature birth rate are needed.