What is Chronic Lung Disease?

Chronic lung disease (CLD), or bronchopulmonary dysplasia, is a long-term respiratory condition occurring in preterm infants. It is a disease that builds slowly, making it difficult to diagnose before it becomes serious. It is usually caused by the infant sustaining a lung injury, which happens easily because the lungs of a premature infant are so fragile.

There are several causes of chronic lung disease. Lung injuries can be caused by ventilator tubes, which are commonly used in newborn infants. Damage can also be done when premature lungs are forced to work before they are fully developed. Too high of a concentration of oxygen can also damage lung tissue. Low amounts of surfactant, which helps to keep air sacs open, can also cause CLD. When the lungs of a preterm infant are damaged it can cause inflammation, which can eventually cause scarring.

Infants born before 34 weeks, and weighing under four and a half pounds (about 2 kgs) are at the greatest risk of developing CLD. Male Caucasian infants have a slightly higher risk, as do children born into a family with a history of asthma problems. Chorioamnionitis, a maternal womb infection, can also increase the chances a preterm infant may be born with chronic lung disease.

Respiratory distress and a prolonged need for mechanical ventilation or oxygen after the infant has reached the age of 36 weeks gestation are both signs of chronic lung disease. It is difficult to catch this disease when it first begins because it progresses so slowly. To diagnose, a doctor will usually send the baby for a chest x-ray. By comparing this new image to previous x-rays, it is possible to see where chronic lung disease has set in. Lungs affected by CLD look like a sponge, or bubbly, when compared to regular lungs.

There are several factors that a doctor will consider before determining a treatment for chronic lung disease. First is the infant’s gestational age, overall health, and medical history. A doctor will also consider how advanced the disease is and the baby’s tolerance of certain medical treatments. The preference of the child’s parents and the expected course of the disease will also be considered.

Medications that help to open airways and reduce inflammation may be used to treat CLD. Extra oxygen may be given to the infant to make up for the limited efficiency of damaged lungs. Infants still requiring mechanical ventilation can be slowly weaned off of the machine as their lungs are encouraged to take over respiratory function on their own. Limiting fluids, to reduce excess fluid in the lungs, and increasing nutrition, to help the infant grow stronger, may also be recommended by a doctor.

Chronic lung disease is a long-term condition. While most children will be able to breathe on their own before leaving the hospital, some infants may still require oxygen for up to a year. Many infants will continue to receive oxygen therapy for a few months after they return home; this is an easy treatment that parents will be shown how to do themselves. The majority of infants with chronic lung disease grow up healthy and strong, leaving their condition behind and living normal lives.