What Is Respiratory Distress Syndrome?

Respiratory distress syndrome (RDS) is a breathing disorder that affects newborns. RDS rarely occurs in full-term infants. The disorder is more common in premature infants born about 6 weeks or more before their due dates.

RDS is more common in premature infants because their lungs aren't able to make enough surfactant (sur-FAK-tant). Surfactant is a liquid that coats the inside of the lungs. It helps keep them open so that infants can breathe in air once they're born.

Without surfactant, the lungs collapse and the infant has to work hard to breathe. He or she might not be able to breathe in enough oxygen to support the body's organs. The lack of oxygen may damage the infant's brain and other organs if proper treatment isn't given.

Most infants who develop RDS show signs of breathing problems and a lack of oxygen at birth or within the first few hours that follow.

Overview

RDS is one of the most common lung disorders in premature infants. It affects about 10 of every 100 premature babies in the United States. In fact, nearly all infants born before 28 weeks of pregnancy develop RDS.

RDS may be an early phase of bronchopulmonary dysplasia (brong-ko-PUL-mo-nar-e dis-PLA-ze-ah), or BPD. This is another breathing disorder that affects premature babies.

RDS usually develops in the first 24 hours after birth. If breathing problems are still present by the time premature infants reach their original due dates, they may be diagnosed with BPD. Some of the life-saving treatments used to treat RDS may cause BPD.

Some infants who have RDS recover and never get BPD. Infants who have RDS and get BPD have lungs that are less developed or more damaged than the infants who recover.

Infants who develop BPD usually have fewer healthy air sacs and tiny blood vessels in their lungs. Both the air sacs and the tiny blood vessels that support them are needed to breathe properly.

Outlook

Due to recent medical advances, most infants who have RDS and weigh more than 2 pounds (or about 1,000 grams) at birth now survive. However, these babies may need some extra medical care after going home.

Some babies develop complications from RDS or its treatments. Serious complications include chronic (ongoing) breathing problems, such as asthma and BPD; blindness; and brain damage.

Revised September 2009