Evaluation of the Local Incidence and Determinants of Bronchopulmonary Dysplasia and Pulmonary Morbidity in Extremely Preterm Infants

  • Author / Creator
    Reichert, Amber E.
  • Prevention and management of bronchopulmonary dysplasia (BPD) and resulting pulmonary morbidity remains one of the greatest challenges of neonatal intensive care. This study of infants from northern and central Alberta had three goals: first, to estimate the incidence and risk factors contributing to the development of BPD; second, to estimate the incidence and risk factors contributing to the development of pulmonary morbidity in early infancy; and third, to evaluate the use of two specific early scoring systems in the prediction of BPD and early pulmonary morbidity. Methods: This observational prospective study was conducted on a cohort of 103 premature infants born at 30% oxygen was needed, the infant required ventilator support at 36 weeks post-menstrual age or oxygen support was required at hospital discharge. Maternal, antenatal and post-natal risk factors, including two pulmonary scoring systems: the Chronic Oxygen Dependency (COD) Score and the Pulmonary Severity (PS) Score, were evaluated by logistic regression in the prediction of BPD and pulmonary morbidity in early infancy. Infants in this cohort were evaluated for the presence of major pulmonary morbidity in the first 6 months post-discharge, including 1) death from a pulmonary cause; 2) pneumonia or sepsis with a positive blood culture or requiring antibiotics for 5 days or more; 3) continued hospitalization or rehospitalization for a pulmonary cause; 4) continued use of oxygen, diuretics or systemic steroids for pulmonary disease; or 5) use of pulmonary medications, including systemic or inhaled bronchodilators and/or corticosteroids or leukotriene receptor antagonists. Results: Overall incidence of moderate to severe BPD was 44.7%. In the univariate analysis, significant risk factors included lower gestational age, birth weight and male gender. Apgar scores at 1 and 5 minutes were significantly lower for infants developing moderate or severe BPD and these infants were significantly less likely to have received antenatal corticosteroids. When controlling for antenatal and postnatal variables, such as duration of ventilation and presence of retinopathy of prematurity, pulmonary scores applied at days 2 and 7 were not significantly associated with the development of BPD. Overall, at 3 months 20.5% of infants were reported as having one or more of the above morbidities. Similarly, 24.5% of infants with six-month follow-up data were reported as having one or more of the above morbidities. In the multivariate analysis, risk factors associated with pulmonary morbidity at six months corrected age included the presence of moderate to severe BPD, younger maternal age, duration of invasive and non-invasive ventilation, COD score at day 7 and history of atopy. The COD and PS scores were significant predictors of pulmonary morbidity at 6 months corrected age, but the prediction improved when applied at 2 days of age compared with scoring at day 7, however the prediction of pulmonary morbidity was not significant at 6 months when controlling for other risk factors. Conclusion: In spite of improvements in neonatal care, the incidence of bronchopulmonary dysplasia remains high in infants requiring prolonged ventilation in spite of improvements in neonatal care. Infants born prematurely are at risk for pulmonary morbidity in early infancy however early prediction models are of limited clinical utility.

  • Subjects / Keywords
  • Graduation date
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.
  • Language
  • Institution
    University of Alberta
  • Degree level
  • Department
    • Department of Public Health Sciences
  • Specialization
    • Clinical Epidemiology
  • Supervisor / co-supervisor and their department(s)
    • Senthilselvan, A. Sentil (Department of Public Health Sciences)
    • Spady, Donald (Department of Public Health Sciences)
  • Examining committee members and their departments
    • Hendson, Leonora (Medical Sciences - Paediatrics)
    • Cheung, Po-Yin (Medical Sciences - Paediatrics)
    • Spady, Donald (Department of Public Health Sciences)
    • Jhangri, Gian (Department of Public Health Sciences)
    • Senthilselvan, Sentil (Department of Public Health Sciences)