Bronchopulmonary dysplasia (BPD) is a chronic lung condition affecting premature infants with underdeveloped lungs. The condition is a form of lung injury that develops after birth as a consequence of medical interventions, like mechanical ventilation, needed to support breathing. This damage to fragile lung tissue can lead to long-term respiratory problems, though the health of most babies with BPD improves as they grow.
Causes and Risk Factors of BPD
The cause of BPD is linked to the incomplete development of a premature infant’s lungs. Babies born very early, especially those more than 10 weeks premature, have delicate lung tissues that are not ready for breathing outside the womb. These underdeveloped lungs have fewer and larger air sacs, called alveoli, which reduces the surface area available for oxygen exchange.
This vulnerability is compounded by the life-saving treatments these infants require. Mechanical ventilators, which push air into the lungs, are necessary to help the baby breathe, but the constant pressure can damage the fragile alveoli. Similarly, high concentrations of supplemental oxygen can cause inflammation and injury to the lung tissue.
Other factors contribute to the risk of BPD. Infections before or after birth, like chorioamnionitis or sepsis, can trigger an inflammatory response that makes the lungs more susceptible to injury. A heart condition common in premature infants called patent ductus arteriosus (PDA) can also increase blood flow to the lungs and lead to fluid buildup.
Recognizing and Diagnosing BPD
Diagnosing BPD begins with observing an infant’s breathing for signs of respiratory distress. Symptoms include persistently rapid breathing, audible grunting with each breath, and flaring of the nostrils. Another sign is chest wall retractions, where the skin pulls in between the ribs as the infant struggles to draw air into their lungs.
A formal diagnosis is based on an infant’s continued need for respiratory support. The primary criterion is the requirement for supplemental oxygen for at least 28 days after birth. To determine the condition’s severity, providers assess the baby’s respiratory status around 36 weeks postmenstrual age. This assessment classifies the BPD as mild, moderate, or severe based on the breathing support still needed.
Physicians use imaging tests to support the diagnosis and understand the extent of lung damage. A chest X-ray may show a characteristic pattern of inflammation, scarring, and overinflated areas resembling a sponge-like texture. In some cases, a chest CT scan is used for a more detailed view of the lung structures.
Treatment Strategies in Infancy
The goal of treating BPD is to support the infant’s breathing while allowing the lungs to grow and heal, balancing assistance with preventing further injury. An infant may initially require a mechanical ventilator, but the clinical team works to wean the baby to less invasive support. This transition often moves to continuous positive airway pressure (CPAP) and then to a nasal cannula providing low-flow oxygen.
Medications are used to manage symptoms and support lung function. Diuretics help reduce fluid buildup in the lungs, making breathing easier. Bronchodilators may be administered to relax and open the airways. A cautious course of corticosteroids might be used to decrease inflammation in the lungs, though this is considered due to potential side effects.
Nutritional support is important for BPD management because lung growth and repair require significant energy. Infants with BPD have higher caloric needs due to the increased effort of breathing. They often receive high-calorie formula or fortified breast milk. Some babies may need to be fed through a nasogastric (NG) tube to ensure they receive adequate nutrition without becoming exhausted.
Long-Term Health and Monitoring
While lung function improves as children with BPD grow, the condition can have lasting health effects. The initial lung injury leads to a higher risk of severe respiratory illnesses during early childhood. Infections like respiratory syncytial virus (RSV), influenza, and pneumonia can be more severe in these children, sometimes requiring hospitalization.
These children may also develop long-term breathing problems that resemble asthma, with symptoms like wheezing and shortness of breath when they have a cold or are exposed to lung irritants. Because of these issues, ongoing monitoring by healthcare professionals is important. Regular follow-up with specialists, such as a pediatric pulmonologist, is recommended to track lung function.
Despite these challenges, the long-term outlook for most children with BPD is positive. With diligent medical care, the majority lead active lives as their lungs continue to grow throughout childhood. In many cases, children outgrow the most severe effects of their early lung injury.