What Causes Bronchopulmonary Dysplasia?

Bronchopulmonary dysplasia (BPD) develops as a result of an infant's lungs becoming irritated or inflamed.

The lungs of premature infants are fragile and often aren't fully developed. They can easily be irritated or injured within hours or days of birth. A number of factors can damage premature infants' lungs.

Mechanical Ventilation

Ventilators are machines that help people breathe. Ventilators use pressure to blow air into the airways and lungs.

Newborns who have breathing problems or can't breathe on their own may need a ventilator to support their breathing. However, the pressure from a ventilator can irritate and harm a premature infant's lungs.

For this reason, doctors use ventilators for premature babies only when absolutely needed. Other times, doctors may use nasal continuous positive airway pressure (NCPAP). NCPAP puts less pressure on babies' lungs than ventilators.

High Levels of Oxygen 

Newborns who have breathing problems may get oxygen therapy (oxygen given through nasal prongs, a mask, or a breathing tube). Oxygen therapy is given to make sure that the infants' brains, hearts, livers, and kidneys get enough oxygen to work properly.

However, high levels of oxygen can inflame the lining of the lungs and injure the airways. Also, high levels of oxygen can slow lung development in premature infants.

Infections

Infections can inflame the underdeveloped lungs of premature infants. This narrows the airways and makes it harder for the babies to breathe. Lung infections also increase the babies' need for extra oxygen and breathing support.

Other Causes

Another possible cause of BPD is patent ductus arteriosus (PDA). PDA is a heart problem that occurs soon after birth in some babies. In PDA, abnormal blood flow occurs between two of the major arteries connected to the heart.

The abnormal blood flow can lead to various problems that may cause a baby to need a ventilator and/or oxygen therapy. These treatments can increase the risk of BPD.

Studies also show that heredity plays a role in causing BPD.