OVERVIEW

What is bronchopulmonary dysplasia?

Bronchopulmonary dysplasia (BPD) refers to a condition in which premature infants cannot wean off supplemental oxygen for an extended period after birth. It is one of the common late complications in preterm infants. Traditional definition: Premature infants who still require oxygen at 28 days postnatal or at a corrected gestational age of 36 weeks can be diagnosed with bronchopulmonary dysplasia.

The diagnostic criteria based on gestational age are divided into the following two categories:

• For preterm infants with a gestational age of less than 32 weeks, assessment is performed either at a corrected gestational age of 36 weeks or at discharge, whichever comes first. Infants who cannot wean off oxygen are diagnosed with bronchopulmonary dysplasia.
• For preterm infants with a gestational age of 32 weeks or more, assessment is performed between 29–55 days postnatal or at discharge, whichever comes first. Infants who cannot wean off oxygen are diagnosed with bronchopulmonary dysplasia.

Can bronchopulmonary dysplasia be cured?

Bronchopulmonary dysplasia is classified into mild, moderate, and severe degrees based on the infant's oxygen requirements.

• Mild bronchopulmonary dysplasia has a better prognosis, and most infants can eventually wean off oxygen after some time.
• Severe bronchopulmonary dysplasia, requiring prolonged mechanical ventilation, carries a high mortality rate.
• Moderate bronchopulmonary dysplasia falls between mild and severe cases. With relatively longer respiratory support and effective treatment, mortality can be significantly reduced.

Mortality increases with prolonged ventilator use. The mortality rate for preterm infants with bronchopulmonary dysplasia requiring ventilation for more than 2 months is 35%.

Does bronchopulmonary dysplasia have long-term complications?

Bronchopulmonary dysplasia may lead to complications such as decreased lung function, tracheobronchial stenosis, subglottic stenosis, tracheobronchomalacia, recurrent pneumonia, and pulmonary hypertension.

Is bronchopulmonary dysplasia common?

Bronchopulmonary dysplasia occurs in premature infants, with the risk increasing with lower gestational age and birth weight.

• The incidence of bronchopulmonary dysplasia in infants born at 28 weeks is 23%.
• The incidence in preterm infants with a birth weight below 1500 g is 40%.

SYMPTOMS

What are the symptoms of bronchopulmonary dysplasia in children?

Due to lung damage, oxygen cannot enter the body. The child may exhibit symptoms such as cyanosis (bluish skin) and rapid breathing.

However, since children with bronchopulmonary dysplasia are usually premature infants who stay in the NICU (Neonatal Intensive Care Unit) after birth, they often do not progress to these symptoms under 24-hour close monitoring of oxygen saturation. Instead, they may only show decreased oxygen saturation levels on monitors, requiring long-term oxygen therapy or ventilator support to meet the body's normal needs.

CAUSES

What are the common causes of bronchopulmonary dysplasia?

• Prematurity: The period between 23 and 32 weeks of gestation is a sensitive phase for lung development, making it vulnerable to external damage. Preterm infants born before 32 weeks have underdeveloped airway support, insufficient pulmonary surfactant, low lung compliance, immature antioxidant mechanisms, and inadequate fluid clearance, all of which increase the risk of postnatal lung injury and structural abnormalities.
• Small-for-gestational-age preterm infants: Preterm infants with a birth weight below the expected gestational age often experience restricted growth, making them more prone to abnormal lung development.
• Mechanical ventilation: Preterm infants requiring ventilator support after birth have a higher likelihood of developing bronchopulmonary dysplasia, as mechanical ventilation can cause damage to the lungs and bronchi.
• High-concentration oxygen therapy: Prolonged exposure to high oxygen concentrations increases the risk of bronchopulmonary dysplasia due to elevated superoxide radical production, which damages lung tissue.
• Infection: Both prenatal maternal infections and postnatal neonatal infections can raise the risk of bronchopulmonary dysplasia, as inflammatory cytokines can damage airway and lung tissue.
• Pulmonary surfactant deficiency: A lack of pulmonary surfactant reduces lung compliance and increases the likelihood of bronchopulmonary dysplasia.
• Early patent ductus arteriosus (PDA): PDA increases pulmonary blood flow, and studies suggest that early PDA is associated with a higher incidence of bronchopulmonary dysplasia.

Which children are more susceptible to bronchopulmonary dysplasia?

• Preterm infants, especially those with lower gestational age and low birth weight, have a higher risk of bronchopulmonary dysplasia.
• Infants with a birth weight below 1,250 g or a gestational age under 30 weeks are at particularly high risk.
• Preterm infants requiring mechanical ventilation after birth.
• Preterm infants with postnatal infections.
• Preterm infants with patent ductus arteriosus (PDA).
• Preterm infants needing high-concentration oxygen therapy.

When does bronchopulmonary dysplasia typically occur?

Symptoms of bronchopulmonary dysplasia usually appear after 28 days of life, though severe cases may manifest earlier.

DIAGNOSIS

When bronchopulmonary dysplasia is suspected, what tests are needed?

Chest X-ray, lung CT, blood gas analysis, cardiac ultrasound, and pulmonary function tests are required.

Why are these tests performed for bronchopulmonary dysplasia?

• Chest X-ray and lung CT: The most intuitive tests to assess lung conditions. Chest X-rays may require repeated follow-ups during the disease course to monitor real-time changes. Lung CT provides clearer details of the lungs and bronchi, making it a crucial diagnostic tool for bronchopulmonary dysplasia.
• Blood gas analysis: Evaluates whether hypoxia is present. This test is often repeated during illness to adjust oxygen concentration and respiratory support.
• Cardiac ultrasound: Determines conditions such as patent ductus arteriosus or pulmonary hypertension.
• Pulmonary function test: Assesses the extent of impaired lung function.

What should be noted when performing these tests for bronchopulmonary dysplasia?

Most preterm infants with bronchopulmonary dysplasia are treated in the NICU, where resident physicians arrange the tests. Blood tests are handled by medical staff. X-rays and ultrasounds may be performed bedside in emergencies without family assistance. For CT scans outside the NICU, families should help stabilize the infant's position as instructed by medical staff.

What are the complications of bronchopulmonary dysplasia?

• Pulmonary hypertension: Long-term bronchopulmonary dysplasia can lead to pulmonary hypertension. Preterm infants with this condition require close cardiac ultrasound monitoring.
• Asthma-like symptoms: Due to lung damage, affected children may experience recurrent wheezing later in life.
• Tracheobronchomalacia: Softening of airways caused by prolonged intubation and mechanical ventilation.
• Subglottic/tracheal/bronchial stenosis: Airway narrowing from long-term intubation, suctioning, or infections.
• Pneumonia: Increased susceptibility to pneumonia in later years.
• Retinopathy of prematurity: High-risk group due to prolonged oxygen therapy, requiring regular eye exams.
• Neurodevelopmental abnormalities: These infants are at high risk for brain injuries and subsequent developmental disorders, necessitating follow-up.
• Feeding difficulties: Common issues include gastroesophageal reflux and swallowing disorders.
• Growth retardation: Frequently associated with delayed physical development.
• Others: Some may develop hearing impairment, sleep-related hypoxemia, or recurrent lower respiratory infections.

TREATMENT

Which department should I visit for bronchopulmonary dysplasia?

Neonatology, Neonatal Intensive Care Unit (NICU), Pediatric Respiratory Medicine, Pediatrics

How is bronchopulmonary dysplasia treated?

Premature infants require comprehensive treatment in the neonatal unit after birth. The main treatments include:

• Implementing lung protection strategies before bronchopulmonary dysplasia occurs to reduce lung damage: Such as shortening ventilator use time, reducing inhaled oxygen concentration, adopting appropriate ventilator parameters, actively using pulmonary surfactants, treating patent ductus arteriosus, and avoiding fluid overload.
• After symptoms of bronchopulmonary dysplasia appear, treatments include:
  • Providing appropriate respiratory support to meet the body's oxygen needs while minimizing inhaled oxygen concentration and ventilator parameters.
  • Ensuring adequate nutrition and energy intake while controlling total fluid intake.
  • Using diuretics to help wean off the ventilator earlier.
  • For severe BPD patients requiring prolonged ventilator support to maintain blood oxygen saturation, systemic corticosteroid therapy may be considered to facilitate earlier ventilator weaning.

What should parents pay attention to during the hospitalization of a child with bronchopulmonary dysplasia?

Most children with bronchopulmonary dysplasia are premature infants with low gestational age and birth weight. They are usually hospitalized in NICU wards without parental accompaniment.

Since the mother and child are separated, and the child is cared for by medical staff, the unstable condition of the child can be emotionally distressing for parents. One important thing parents can do is maintain breast milk production. For premature infants, breast milk is more beneficial than formula.

Using an electric breast pump and storing breast milk in frozen storage bags allows the milk to be delivered to the ward for the child to consume. Alternatively, breastfeeding can continue after discharge. Both options are beneficial. Maintaining breast milk production is highly advantageous for the child.

For children with bronchopulmonary dysplasia, doctors may also recommend using breast milk fortifiers in addition to breastfeeding, as fortified breast milk provides higher energy and is more suitable for recovery.

In wards where parents can stay, the primary focus should be on cooperating with medical treatment. Parents should wash hands before touching the child. If respiratory care is needed—such as repositioning, post-feeding burping, or back patting before suctioning—parents can learn the proper techniques from nurses. Frequently changing the child's position and avoiding prolonged lying flat can aid recovery. For children on oxygen or cardiac monitoring, parents should consult nurses to understand which readings require immediate medical attention.

Do children with bronchopulmonary dysplasia need follow-up after discharge?

Regular follow-up visits are necessary after discharge, following the premature infant follow-up plan. Evaluations mainly include neurological, eye, hearing, and physical development assessments. For premature infants discharged with home oxygen therapy, an individualized follow-up plan should be designed by the original attending physician.

DIET & LIFESTYLE

What should children with bronchopulmonary dysplasia pay attention to in their diet?

• The nutritional needs for bronchopulmonary dysplasia are high energy and low fluid volume.
• Fortified breast milk or high-calorie preterm formula is the preferred dairy product.
• Dietary management requires guidance from a professional neonatologist and should be adjusted individually based on the child's growth and development.

What should children with bronchopulmonary dysplasia or their caregivers pay attention to in daily life?

• For children discharged with oxygen: When using a home oxygen concentrator, ensure proper use of the oxygen saturation probe and monitor changes in oxygen saturation levels. Adjust oxygen concentration based on these changes. Seek immediate medical help if the child shows signs like cyanosis (bluish skin) or rapid breathing.
• For children discharged without oxygen: Complete regular follow-ups for preterm infants. Avoid close contact with visitors or other children. Adults should wash hands and change clothes before interacting with the child to minimize the risk of respiratory infections. Children with bronchopulmonary dysplasia are prone to wheezing and pneumonia, so avoid exposure to irritants like secondhand smoke, dust mites, vehicle exhaust, and air pollution.
• Family members should get annual flu vaccinations to reduce the child's risk of influenza. Additionally, the child should receive all recommended vaccines under the evaluation and guidance of a specialist.

PREVENTION

Can Bronchopulmonary Dysplasia Be Prevented?

Possible preventive measures include:

• Regular prenatal check-ups for pregnant women. If high-risk factors for preterm birth are identified, active treatment should be administered to reduce premature delivery and prolong gestational age, which can fundamentally lower the risk of bronchopulmonary dysplasia.
• Administering corticosteroids to pregnant women before preterm delivery to promote fetal lung maturation, thereby reducing the incidence of bronchopulmonary dysplasia.
• After preterm birth, minimizing the infant's exposure to oxygen during resuscitation to avoid lung damage from hyperoxia. Additionally, promoting breastfeeding, supplementing with vitamin A, administering caffeine therapy when necessary, and preventing iatrogenic infections.
• Actively treating neonatal respiratory distress syndrome. Timely use of pulmonary surfactants to shorten ventilator use and reduce oxygen dependency.
• Adopting lung-protective strategies when using ventilators or oxygen therapy.
• Treating patent ductus arteriosus to prevent abnormal pulmonary blood flow.