Respiratory Distress Syndrome Causes, Symptoms, Diagnosis, Treatment, Prevention

Respiratory Distress Syndrome Causes, Symptoms, Diagnosis, Treatment, Prevention

What is respiratory distress syndrome?

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

Respiratory distress syndrome 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 enough 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 can damage the baby's brain and other organs if proper treatment isn't given.

Most babies who develop respiratory distress syndrome show signs of breathing problems and a lack of oxygen at birth or within the first few hours that follow.

What does a baby with Respiratory Distress Syndrome look like?

The baby will have difficulty breathing. S/he will have:

  • rapid breathing
  • pulling in of the ribs and center of the chest with each breath, called retractions.
  • an "ugh" sound with each breath, called grunting.
  • widening of the nostrils with each breath, called flaring.

What Causes Respiratory Distress Syndrome?

Respiratory distress syndrome occurs when there is not enough of a substance in the lungs called surfactant. Surfactant is a liquid produced by the lungs that keeps the airways (called alveoli) open, making it possible for babies to breathe in air after delivery. It begins to be produced in the fetus at about 26 weeks of pregnancy.

When there is not enough surfactant, the tiny alveoli collapse with each breath. As the alveoli collapse, damaged cells collect in the airways and further affect breathing ability. The baby works harder and harder at breathing, trying to reinflate the collapsed airways.

As the baby's lung function decreases, less oxygen is taken in and more carbon dioxide builds up in the blood. This can lead to increased acid in the blood called acidosis, a condition that can affect other body organs. Without treatment, the baby becomes exhausted trying to breathe and eventually gives up. A mechanical ventilator (breathing machine) must do the work of breathing instead.

Some full-term infants develop respiratory distress syndrome because they have faulty genes that affect how their bodies make surfactant.

Who is affected by Respiratory Distress Syndrome?

Respiratory distress syndrome occurs most often in babies born before 28 weeks gestation. Some premature babies develop respiratory distress syndrome severe enough to need a mechanical ventilator (breathing machine). The more premature the baby, the higher the risk and the more severe the RDS.

Although most babies with respiratory distress syndrome are premature, other factors can influence the chances of developing the disease. These include the following:

  • White or male babies
  • Previous birth of baby with respiratory distress syndrome
  • Cesarean delivery
  • Perinatal asphyxia
  • Cold stress (a condition that suppresses surfactant production)
  • Perinatal infection
  • Multiple births (multiple birth babies are often premature)
  • Infants of diabetic mothers (too much insulin in a baby's system due to maternal diabetes can delay surfactant production)
  • Babies with patent ductus arteriosus

What are the symptoms of Respiratory Distress Syndrome?

The following are the most common symptoms of respiratory distress syndrome. However, each baby may experience symptoms differently. Symptoms may include:

  • Respiratory difficulty at birth that gets progressively worse
  • Cyanosis (blue coloring)
  • Flaring of the nostrils
  • Tachypnea (rapid breathing)
  • Grunting sounds with breathing
  • Chest retractions (pulling in at the ribs and sternum during breathing)

The symptoms of respiratory distress syndrome usually peak by the third day, and may resolve quickly when the baby begins to diurese (excrete excess water in urine). When a baby improves, he or she begins to need less oxygen and mechanical help to breathe.

The symptoms of respiratory distress syndrome may resemble other conditions or medical problems. Always consult your baby's doctor for a diagnosis.

Respiratory Distress Syndrome Complications

Depending on the severity of an infant's respiratory distress syndrome, he or she may develop other medical problems.

Lung Complications

Lung complications may include a collapsed lung (atelectasis), leakage of air from the lung into the chest cavity (pneumothorax), and bleeding in the lung (hemorrhage).

Some of the life-saving treatments used for respiratory distress syndrome may cause bronchopulmonary dysplasia, another breathing disorder.

Blood and Blood Vessel Complications

Infants who have respiratory distress syndrome may develop sepsis, an infection of the bloodstream. This infection can be life threatening.

Lack of oxygen may prevent a fetal blood vessel called the ductus arteriosus from closing after birth as it should. This condition is called patent ductus arteriosus, or PDA.

The ductus arteriosus connects a lung artery to a heart artery. If it remains open, it can strain the heart and increase blood pressure in the lung arteries.

Other Complications

Complications of respiratory distress syndrome also may include blindness and other eye problems and a bowel disease called necrotizing enterocolitis (EN-ter-o-ko-LI-tis). Infants who have severe respiratory distress syndrome can develop kidney failure.

Some infants who have respiratory distress syndrome develop bleeding in the brain. This bleeding can delay mental development. It also can cause mental retardation or cerebral palsy.

How is Respiratory Distress Syndrome diagnosed?

Respiratory distress syndrome is usually diagnosed by a combination of assessments, including the following:

Appearance, color, and breathing efforts (indicate a baby's need for oxygen).

Chest X-rays of lungs. X-rays are electromagnetic energy used to produce images of bones and internal organs onto film.

Blood gases (tests for oxygen, carbon dioxide and acid in arterial blood). These often show lowered amounts of oxygen and increased carbon dioxide.

Echocardiography. Sometimes used to rule out heart problems that might cause symptoms similar to respiratory distress syndrome. Echocardiography is a type of ultrasound that looks specifically at the structure and function of the heart.

How Is Respiratory Distress Syndrome Treated?

Treatment for respiratory distress syndrome usually begins as soon as an infant is born, sometimes in the delivery room.

Most infants who show signs of respiratory distress syndrome are quickly moved to a neonatal intensive care unit (NICU). There they receive around-the-clock treatment from health care professionals who specialize in treating premature infants.

Surfactant Replacement Therapy

Surfactant is a liquid that coats the inside of the lungs. It helps keep them open so that an infant can breathe in air once he or she is born.

Babies who have respiratory distress syndrome are given surfactant until their lungs are able to start making the substance on their own. Surfactant usually is given through a breathing tube. The tube allows the surfactant to go directly into the baby's lungs.

Once the surfactant is given, the breathing tube is connected to a ventilator, or the baby may get breathing support from NCPAP.

Surfactant often is given right after birth in the delivery room to try to prevent or treat respiratory distress syndrome. It also may be given several times in the days that follow, until the baby is able to breathe better.

Some women are given medicines called corticosteroids during pregnancy. These medicines can speed up surfactant production and lung development in a fetus. Even if you had these medicines, your infant may still need surfactant replacement therapy after birth.

Breathing Support

Infants who have respiratory distress syndrome often need breathing support until their lungs start making enough surfactant. Until recently, a mechanical ventilator usually was used. The ventilator was connected to a breathing tube that ran through the infant's mouth or nose into the windpipe.

Today, more and more infants are receiving breathing support from NCPAP. NCPAP gently pushes air into the baby's lungs through prongs placed in the infant's nostrils.

Oxygen Therapy

Infants who have breathing problems may get oxygen therapy. Oxygen is given through a ventilator or NCPAP machine, or through a tube in the nose. This treatment ensures that the infants' organs get enough oxygen to work well.

Other Treatments

Other treatments for respiratory distress syndrome include medicines, supportive therapy, and treatment for patent ductus arteriosus (PDA). PDA is a condition that affects some premature infants.


Doctors often give antibiotics to infants who have respiratory distress syndrome to control infections (if the doctors suspect that an infant has an infection).

Supportive Therapy

Treatment in the NICU helps limit stress on babies and meet their basic needs of warmth, nutrition, and protection. Such treatment may include:

  • Using a radiant warmer or incubator to keep infants warm and reduce the risk of infection.
  • Ongoing monitoring of blood pressure, heart rate, breathing, and temperature through sensors taped to the babies' bodies.
  • Using sensors on fingers or toes to check the amount of oxygen in the infants' blood.
  • Giving fluids and nutrients through needles or tubes inserted into the infants' veins. This helps prevent malnutrition and promotes growth. Nutrition is critical to the growth and development of the lungs. Later, babies may be given breast milk or infant formula through feeding tubes that are passed through their noses or mouths and into their throats.
  • Checking fluid intake to make sure that fluid doesn't build up in the babies' lungs.

Treatment for Patent Ductus Arteriosus

PDA is a possible complication of respiratory distress syndrome. In this condition, a fetal blood vessel called the ductus arteriosus doesn't close after birth as it should.

The ductus arteriosus connects a lung artery to a heart artery. If it remains open, it can strain the heart and increase blood pressure in the lung arteries.

PDA is treated with medicines, catheter procedures, and surgery.

How Can Respiratory Distress Syndrome Be Prevented?

Taking steps to ensure a healthy pregnancy might prevent your infant from being born before his or her lungs have fully developed.

The best way of preventing respiratory distress syndrome is to delay delivery until the fetal lungs have matured and are producing enough surfactant, generally at about 37 weeks of pregnancy. If delivery cannot be delayed, the mother may be given a steroid hormone, similar to a natural substance produced in the body, which crosses the barrier of the placenta and helps the fetal lungs to produce surfactant. The steroid should be given at least 24 hours before the expected time of delivery. If the infant does develop respiratory distress syndrome, the risk of bleeding into the brain will be much less if the mother has been given a dose of steroid.

If a very premature infant is born without symptoms of respiratory distress syndrome, it may be wise to deliver surfactant to its lungs. This may prevent respiratory distress syndrome or make it less severe if it does develop. An alternative is to wait until the first symptoms of respiratory distress syndrome appear and then immediately give surfactant. Pneumothorax may be prevented by frequently checking the blood oxygen content and limiting oxygen treatment under pressure to the minimum needed.

Your doctor may give you injections of a corticosteroid medicine if he or she thinks you may give birth too early. This medicine can speed up surfactant production and development of the lungs, brain, and kidneys in your baby.

Treatment with corticosteroids can reduce your baby's risk of respiratory distress syndrome . If the baby does develop respiratory distress syndrome, it will probably be fairly mild.

Corticosteroid treatment also can reduce the chances that your baby will have bleeding in the brain.

How long does Respiratory Distress Syndrome last?

For each baby the course is different. The disease usually gets worse for about 3-4 days. Then, the baby gradually needs less added oxygen. If a baby has relatively mild disease and has not needed a breathing machine, s/he may be off oxygen in 5-7 days. If a baby has more severe disease there is also improvement after 3-5 days but the improvement may be slower and the baby may need extra oxygen and/or a ventilator for days to weeks. Recovery is slower if:

  • the baby is very tiny (<2 1/2 pounds at birth)
  • the baby's disease was severe (required high oxygen and ventilator settings in the first days)
  • the baby also had infection
  • the baby had complications such as Pneumothorax, Pulmonary Interstitial Emphysema or Patent Ductus Arteriosus

Living With Respiratory Distress Syndrome

Caring for a premature infant can be challenging. You may experience:

  • Emotional distress, including feelings of guilt, anger, and depression.
  • Anxiety about your baby's future.
  • A feeling of a lack of control over the situation.
  • Financial stress.
  • Problems relating to your baby while he or she is in the neonatal intensive care unit (NICU).
  • Fatigue (tiredness).
  • Frustration that you can't breastfeed your infant right away. (You can pump and store your breast milk for later use.)

Take Steps to Manage Your Situation

You can take steps to help yourself during this difficult time. For example, take care of your health so that you have enough energy to deal with the situation.

Learn as much as you can about what goes on in the NICU. You can help your baby during his or her stay there and begin to bond with the baby before he or she comes home.

Learn as much as you can about your infant's condition and what's involved in daily care. This will allow you to ask questions and feel more confident about your ability to care for your baby at home.

Seek out support from family, friends, and hospital staff. Ask the case manager or social worker at the hospital about what you'll need after your baby leaves the hospital. The doctors and nurses can assist with questions about your infant's care. Also, you may want to ask whether your community has a support group for parents of premature infants.

Parents are encouraged to visit their baby in the NICU as much as possible. Spend time talking to your baby and holding and touching him or her (when allowed).

Ongoing Care for Your Infant

Your baby may need special care after leaving the NICU, including:

  • Special hearing and eye exams
  • Speech or physical therapy
  • Specialty care for other medical problems caused by premature birth
Talk to your child's doctor about ongoing care for your infant and any other medical concerns you have.


If an infant born with respiratory distress syndrome is not promptly treated, lack of an adequate oxygen supply will damage the body's organs and eventually cause them to stop functioning altogether. Death is the result. The central nervous system in particular—made up of the brain and spinal cord—is very dependent on a steady oxygen supply and is one of the first organ systems to feel the effects of respiratory distress syndrome. By contrast, if the infant's breathing is supported until the lungs mature and make their own surfactant, complete recovery within three to five days is the pattern.

If an air leak causes pneumothorax, immediate removal of air from the chest allows the lungs to re-expand. Bleeding into the brain is a very serious condition that worsens the outlook for an infant with respiratory distress syndrome.