Arrest of Lung Development
Chronic Lung Disease of Prematurity or Infancy
Evolving Chronic Lung Disease
Neonatal Chronic Lung Disease
Respiratory Insufficiency

P27.1, Bronchopulmonary dysplasia originating in the perinatal period
Z99.81, Dependence on supplemental oxygen
90772, Injection of palivizumab
90378, Palivizumab (Synagis) serum for intramuscular use

BPD is a form of chronic respiratory disease manifested by the persistent need for supplemental oxygen (fraction of inspired oxygen >21%) for more than 28 days after birth. [Jobe: 2001] Diagnosis of BPD is currently based entirely on clinical course rather than exam, lab results, or imaging findings. However, chest radiographs from the neonatal intensive care unit (NICU) stay of infants with BPD may show:

• Central airway abnormalities (tracheobronchomalacia or narrowing/stenosis)
• Structural remodeling, hyperreactivity, and bronchoconstriction of the small airways
• Decreased alveolarization and vascular remodeling in the distal airspaces and pulmonary vasculature

Classification of BPD has been evolving due to changes in care received in the NICU. Generally, BPD severity is categorized as mild, moderate, or severe.

• For infants born <32 weeks gestation, BPD severity grading of mild, moderate, or severe is determined at postmenstrual age of 36 weeks based on level of supplemental O2 need (FiO2 at room air, <30% or >30%) and/or need for positive pressure support (high-flow nasal cannula, CPAP, or positive pressure ventilation).
• For infants born at greater than 32 weeks gestation, BPD severity is similarly based on the date of discharge or by 56 days of life, whichever comes first. [Jobe: 2001]

More severe BPD correlates with greater likelihood of respiratory and neurocognitive morbidities. [Thébaud: 2019] Similarly, prolonged length of NICU stay has been associated with severity of neurocognitive morbidity. [Bauer: 2020]

Respiratory

Infants and children with BPD may present with tachypnea, mild subcostal retractions, or increased anterior posterior diameter (barrel chest). Infants may have sporadic cough or signs of reflux (e.g., back-arching, fussiness). Wheezing, heavy breathing, or noisy breathing may be heard if there is associated laryngomalacia or tracheomalacia or intercurrent illness. In older children, there may be abnormal chest wall development with bilateral concavity of the lower chest wall from chronic subcostal retractions.

When establishing care, inquire about “baseline” retractions. At future visits, monitor for changes in the work of breathing compared to baseline.

Skin

Reactions to adhesives can occur where stickers are used to anchor the nasal cannula. Counsel the family to use skin protectant and adhesive remover.

Because children with BPD related to prematurity are at increased risk of emergency room visits and hospitalizations related to respiratory infections in the first 2 years of life, as well as increased risk of developing chronic obstructive pulmonary disease, the goals of management in the medical home include:

• Optimizing nutrition and growth
• Providing adequate outpatient oxygen therapy and weaning when able
• Preventing complications through targeted immunizations and avoidance of respiratory pathogens and pollutants
• Monitoring for and treating comorbid conditions
• Providing family support and answering questions
• Coordinating interdisciplinary care with specialists such as pediatric pulmonologists

Respiratory

• Refer to Pulmonology or provide for serial monitoring of lung function (spirometry) to assess for the development of obstructive (e.g., asthma, tracheobronchomalacia, etc.) and/or restrictive lung disease. The chronic lung disease of children with BPD often shows airflow obstruction and intermittent pulmonary exacerbations and can be frequent in the first 2 years of life. Long-term lung function of children and adults with a history of BPD has, on average, lower lung function (FEV1) compared to children and adult controls born at term. All children with BPD should have complete pulmonary function testing, typically starting at age 4 or 5 years. [McGrath-Morrow: 2019]
• Provide home oxygen therapy for children with chronic hypoxemia and wean as tolerated. Home pulse oximetry studies while sleeping or serial clinic evaluations of oxygen saturations can be used to monitor progress and to wean off oxygen therapy used at home and during car seat use.
• If there is persistent nocturnal hypoxemia or signs and symptoms of sleep-disordered breathing (e.g., snoring, restless sleep), refer for a polysomnography/sleep study to assess for sleep-disordered breathing (e.g., obstructive and/or central sleep apnea).
• Refer to ENT or Pulmonology to perform airway endoscopy to assess for possible upper and lower airway abnormalities such as suspected tracheobronchomalacia and to develop a co-management plan. Management of abnormalities may require additional investigation (e.g., modified barium swallow study), medications, initiation of non-invasive positive pressure (CPAP), or surgical interventions.
• Obtain echocardiogram to screen for pulmonary hypertension every 4-6 months for children with moderate to severe BPD who are at the highest risk for developing pulmonary hypertension. This is typically in the first 1-2 years of life. Risk factors include poor growth and history of pulmonary hypertension in the NICU.

Nutrition and Growth

• Monitor carefully and ensure adequate nutrition, including calories and protein. Linear growth is particularly important for lung growth. See the Portal's Premature Infant Follow-Up for more information on feeding and nutrition in this population.

Infectious Disease

• Provide routine childhood immunization including influenza annually and pneumococcal vaccinations.
• Administer palivizumab (Synagis) to eligible children <24 months of age to prevent serious lung disease from RSV infection. [American: 2014] For a summary of recommendations, see RSV Recommendations (AAP).
• Administer expanded pneumonia vaccine, PPSV-23, at ≥2 years of age, at least 8 weeks after completing PCV-13. PPSV-23 is recommended for all children with chronic lung disease (BPD is considered a CLD of prematurity/infancy) in children ≥2 years of age. A second dose of PPSV-23 is recommended 5 years after the first dose after age 2 years to targeted populations for children who have anatomic or functional asplenia, including SCD, HIV infection, or other immunocompromising condition. [Nuorti: 2010]

Comorbidities that may occur in infants with BPD include gastroesophageal reflux, dysphagia, aspiration, sleep-disordered breathing (including obstructive and central sleep apnea), atelectasis, pulmonary hypertension, developmental delays, and cerebral palsy. [Gou: 2018] Studies are underway to better understand the rates of comorbidities.

Imaging

After discharge from the NICU, there is generally no need for repeated imaging of children with known BPD if they improve as expected and wean off oxygen. For those patients that do not improve as expected, consider the following:

• Consider chest radiographs to differentiate complications such as aspiration pneumonitis, reactive airways disease, chronic atelectasis, or bacterial pneumonia.
• In severe cases, pediatric pulmonologists might utilize bronchoscopy or chest CT to evaluate for complications such as tracheobronchomalacia, and parenchymal or cystic disease.
• In cases where airway abnormalities are suspected (presence of stridor, noisy breathing, poor sleep, etc.), refer to Pediatric Pulmonology (see NW providers [0]) to perform airway endoscopy to assess upper and lower airway abnormalities (e.g., tracheobronchomalacia, bronchiectasis, interstitial lung disease).
• Obtain echocardiogram to screen for pulmonary hypertension every 4-6 months for children with BPD at high risk of developing pulmonary hypertension, typically in the first 1-2 years of life. Children with severe BPD, or moderate BPD with poor growth, are at the highest risk of developing pulmonary hypertension. Children with a history of BPD who show poor growth or inability to wean off supplemental oxygen (chronic hypoxemia) should undergo echocardiogram screening for pulmonary hypertension.
• A chest CT with angiogram may be used to assess for vascular anomalies such as pulmonary vein stenosis or pulmonary hypertension.

Labs

None needed routinely. Consider a capillary or venous blood gas if the infant is ill-appearing and in respiratory distress.

Pulse Oximetry

Many infants with BPD have chronic hypoxemia and will need to wean off oxygen as an outpatient. Pulse oximetry is recommended in the home for oxygen therapy monitoring. Monitoring oxygen while feeding and sleeping can provide insight into what the infant or child’s ongoing requirement is because O2 levels tend to drop during feeding and sleeping.

For weaning off supplemental oxygen used in car seats, guidelines include oxygen saturation not falling <90% for >10 seconds or heart rate < 80 bpm for >10 seconds on room air, for at least 90 minutes or the duration of the car ride (whichever is longer). Nocturnal home oximetry studies are helpful in determining readiness to wean off supplemental O2 while sleeping. Home oxygen therapy is recommended for children with BPD complicated by chronic hypoxemia. Chronic hypoxemia is defined as either: 1) greater or equal to 5% of recording time spent with SpO2 93% or less during a continuous recording, or 2) at least 3 separate findings of an SpO2 less than or equal to 93% measured intermittently. [Hayes: 2019]

Refer if the child still requires supplemental oxygen 2 months after discharge from NICU (or around CGA 2 months), has chronic respiratory symptoms, or difficult to manage reactive airways disease or asthma. All children with severe BPD or moderate BPD with poor growth should be seen by Pulmonology outpatient. Lung function testing should be performed for children with BPD, typically starting at age 4-5 years. Refer to a sleep medicine pulmonologist if there are signs and symptoms of sleep-disordered breathing (e.g., apneas, snoring, pauses in sleep, or restless sleep) or persistent nocturnal hypoxemia. Pediatric Pulmonology (see NW providers [0])

Refer all children with poor growth. Furthermore, keep in mind that good growth, particularly linear growth, is associated with resolution of symptoms; therefore, nutrition assessment should be considered in all patients with severe BPD. Dieticians and Nutritionists (see NW providers [1])

Refer children with signs/symptoms of dysphagia or aspiration. Feeding & Swallowing Disorders (see NW providers [0])

Refer for faltering growth, failure to thrive, feeding difficulties, severe GER, constipation, or consideration of G-tube placement. Pediatric Gastroenterology (see NW providers [0])

Refer if there are shunt lesions (e.g., PDA, ASD, VSD), history of pulmonary hypertension, abnormal echocardiogram, or EKGs. Pediatric Cardiology (see NW providers [0])

Refer for signs and symptoms of upper airway obstruction, such as noisy breathing, stridor, or concerns for anatomy airway abnormalities (e.g., moderate to severe laryngomalacia, laryngeal cleft, tracheomalacia, vocal cord paralysis or paresis, enlarged tonsils or adenoids). Pediatric Otolaryngology (ENT) (see NW providers [1])