Physiologic Definition of Bronchopulmonary Dysplasia
Condition: Infant, Newborn; Infant, Low Birth Weight; Infant, Small for Gestational Age; Infant, Premature; Bronchopulmonary Dysplasia (BPD)
MeSH terms: Bronchopulmonary Dysplasia; Birth Weight
Study type: Observational

Summary: 
      This observational study was conducted to design and test a physiologic definition for
      bronchopulmonary dysplasia at 36 weeks of life. Infants were studied in a supine position
      with the pulse oximeter in position with good signal prior to collecting baseline data.
      Feedings and medications were given 30 minutes before the evaluation. Baseline data was
      collected on infant's current oxygen. Then, the infants were weaned to room air for 30
      minutes. If saturations remain ≥90%, the infant was considered to have passed the oxygen
      reduction challenge (to NOT have BPD). The infant should then be placed back in his/her
      baseline oxygen. If the infant has saturations <90% for 5 continuous minutes or <80% for 15
      seconds, the infant should be immediately placed back in his/her baseline oxygen, and the
      infant was considered to have NOT passed the challenge (to have BPD).
    

Detailed description: 
      One of the confounders to any study that looks at bronchopulmonary dysplasia (BPD) is the
      lack of a precise definition. Most neonates with BPD do not undergo lung biopsy or any
      physiologic test; thus, their pulmonary disease is defined clinically, on the basis of the
      sustained need for supplemental oxygen at 36 weeks postmenstrual age. The validity of this
      definition is supported by evidence that oxygen dependence at 36 weeks is predictive of
      long-term impairment in pulmonary function. An inherent limitation of defining BPD by the
      need for supplemental oxygen is that the need for oxygen is determined by individual
      physicians, rather than on the basis of a physiologic assessment. Published literature cites
      acceptable saturation ranges from 88-98%.

      This observational study was conducted to design and test a physiologic definition for
      bronchopulmonary dysplasia at 36 weeks of life.

      Infants were studied in a supine position with the pulse oximeter in position with good
      signal prior to collecting baseline data. Feedings and medications were given 30 minutes
      before the evaluation. Baseline data was collected on infant's current oxygen. Then, the
      infants were weaned to room air for 30 minutes. If saturations remain ≥90%, the infant was
      considered to have passed the oxygen reduction challenge (to NOT have BPD). The infant should
      then be placed back in his/her baseline oxygen. If the infant has saturations <90% for 5
      continuous minutes or <80% for 15 seconds, the infant should be immediately placed back in
      his/her baseline oxygen, and the infant was considered to have NOT passed the challenge (to
      have BPD).
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Premature infants on mechanical ventilation at 36 weeks of life.
      
Keywords: NICHD Neonatal Research Network; Extremely Low Birth Weight (ELBW); Very Low Birth Weight (VLBW); Prematurity; Mechanical ventilation; Chronic Lung Disease (CLD)