Bronchopulmonary Dysplasia (BPD)
What is Bronchopulmonary Dysplasia?
Bronchopulmonary dysplasia (BPD) is a term used to describe long-term breathing problems for premature babies. It involves abnormal development of the lungs, and in the most severe cases the lungs are scarred and inflamed.
BPD develops most often in premature babies born with underdeveloped lungs. It is also called chronic lung disease.
- "Broncho" refers to the airways (the bronchial tubes) through which the oxygen we breathe travels into the lungs.
- "Pulmonary" refers to the lungs' tiny air sacs (alveoli), where oxygen and carbon dioxide are exchanged.
- "Dysplasia" means abnormal changes in the structure or organization of a group of cells. The cell changes in BPD take place in the smaller airways and lung alveoli, making breathing difficult and causing problems with lung function.
What are the Symptoms?
Symptoms vary from child to child, but they can include:
- Respiratory distress: Babies with BPD may breathe quickly, flare their nostrils, grunt or show signs of “pulling” at the chest (chest retractions).
- Assisted breathing: Babies who still need to use a breathing machine or oxygen after 36 weeks gestation (adjusted) may have BPD.
What Causes BPD?
Most BPD cases occur in premature infants: usually those who are born at 32 weeks gestation or before and weigh less than 4.5 pounds (2,000 grams). These babies are more likely to be affected by infant respiratory distress syndrome (RDS), and are often on a mechanical ventilator for a longer period of time.
- Mechanical ventilators “breathe” for babies whose lungs are too immature to allow them to breathe on their own and supply oxygen to their lungs.
- Oxygen is delivered through a tube inserted into the baby's trachea (windpipe) and is given under pressure from the machine to properly move air into stiff, underdeveloped lungs.
- Sometimes, for these babies to survive, the amount of oxygen given must be higher than the oxygen concentration in the air we normally breathe.
- Although mechanical ventilation is essential to their survival, over time the pressure from the ventilation and excess oxygen intake can injure a newborn's delicate lungs, leading to RDS.
- Almost half of all extremely low birth weight infants will develop some form of RDS. If symptoms persist, then the condition will be considered BPD if a baby is oxygen dependent at 36 weeks postconceptional age.
BPD also can arise from other adverse conditions that a newborn's fragile lungs have difficulty coping with, such as:
- Congenital malformations of the lung
- Other infections
All of these can cause the inflammation and scarring associated with BPD, even in a full-term newborn or, very rarely, in older infants and children.
Among babies who are premature and have a low birth weight, white male infants seem to be at greater risk for developing BPD, for reasons unknown to doctors. Genetics may contribute to some cases of BPD as well.
How is BPD Diagnosed?
Important factors in diagnosing BPD include:
- Mechanical ventilator dependence
- Oxygen exposure
BPD is typically diagnosed if an infant still requires additional oxygen and continues to show signs of respiratory problems after 28 days of age (or past 36 weeks postconceptional age).
Chest X-rays may be helpful in making the diagnosis. In babies with RDS, the X-rays may show lungs that look like ground glass. In babies with BPD, the X-rays may show lungs that appear spongy.
Your child’s doctor may use blood tests. They may also use a test called an echocardiogram to rule out heart defects as the cause of your child’s breathing issues.
How is BPD Treated?
There is no cure for BPD, but it can be treated. Treatment is geared toward supporting breathing and oxygen needs and enabling children with BPD to grow and thrive.
- Babies first diagnosed with BPD receive intense supportive care in the hospital until they are able to breathe well enough on their own without the support of a mechanical ventilator.
- Infants with BPD are also treated with different kinds of medications that help to support lung function. These include bronchodilators (such as albuterol) to help keep the airways open, and diuretics (such as furosemide) to reduce fluid buildup in the lungs. Severe cases of BPD might be treated with a short course of corticosteroids (not to be confused with anabolic steroids used by athletes) to reduce inflammation in the lungs.
- Antibiotics are sometimes needed to fight bacterial infections because babies with BPD are more likely to develop pneumonia.
The time spent in the NICU for infants with BPD can range from several weeks to a few months. Even after leaving the hospital, a baby might require continued medication, breathing treatments or even oxygen at home.