Neonatal RDS occurs in infants whose lungs have not yet fully developed.
The disease is mainly caused by a lack of a slippery substance in the lungs called surfactant. This substance helps the lungs fill with air and keeps the air sacs from deflating. Surfactant is present when the lungs are fully developed.
Neonatal RDS can also be due to genetic problems with lung development.
Most cases of RDS occur in babies born before 37 weeks. The less the lungs are developed, the higher the chance of RDS after birth. The problem is uncommon in babies born full-term (at 40 weeks).
Other factors that can increase the risk of RDS include:
A brother or sister who had RDS
Diabetes in the mother
Cesarean delivery or induction of labor before the is full-term
Problems with delivery that reduce blood flow to the baby
Multiple pregnancy (twins or more)
Most of the time symptoms appear within minutes of birth. However, they may not be seen for several hours. Symptoms may include:
Bluish color of the skin and mucus membranes (cyanosis)
Brief stop in breathing (apnea)
Decreased urine output
Shortness of breath and grunting sounds while breathing
Unusual breathing movement (such as drawing back of the chest muscles with breathing)
Signs and tests
The following tests are used to detect the condition:
Blood gas analysis -- shows low oxygen and excess acid in the body fluids
Chest x-ray -- shows a "ground glass" appearance to the lungs that is typical of the disease. This often develops 6 to 12 hours after birth.
Lab tests – rule out infection as a cause of breathing problems
Babies that are premature or high risk for the problem need to be treated at birth by a medical team that specializes in newborn breathing problems.
Giving artificial surfactant to an infant has been shown to be helpful. More research still needs to be done on which babies should get this treatment and how much of the substance to use.
Infants will be given warm, moist oxygen. However, this treatment needs to be monitored carefully to avoid side effects from too much oxygen.
A breathing machine can be lifesaving for some babies. Breathing machines can damage the lung tissue so use should be avoided when possible. Babies may need to use a breathing machine if they have:
High levels of carbon dioxide in the arteries
Low blood oxygen in the arteries
Low blood pH (acidity)
Repeated pauses in breathing
A treatment called continuous positive airway pressure (CPAP) may prevent the need for a breathing machine in many babies. CPAP uses a device that sends air into the nose to help keep the airways open.
Babies with RDS need close care. This includes:
Having a calm setting
Staying at an ideal body temperature
Carefully managing fluids and nutrition
Treating infections right away
The condition often gets worse for 2 to 4 days after birth. It often improves slowly after that. Some infants with severe respiratory distress syndrome will die. If this occurs, it often happens between days 2 and 7.
Long-term complications may develop due to:
Too much oxygen
High pressures delivered to the lungs
More severe disease. When RDS is worse, it can result in inflammation that causes lung or brain damage.
Periods when the brain or other organs did not get enough oxygen
Air or gas may build up in:
The space surrounding the lungs (pneumothorax)
The space in the chest between two lungs (pneumomediastinum)
The area between the heart and the thin sac that surrounds the heart (pneumopericardium)
Most of the time, this problem develops shortly after birth while the baby is still in the hospital. If you have given birth at home or outside a medical center, get emergency help if your baby has breathing problems.
Taking steps to prevent premature birth can help prevent neonatal RDS. Good prenatal care and regular checkups beginning as soon as a woman discovers she is pregnant can help avoid premature birth.
The risk of RDS can also be lessened by the proper timing of a Cesarean delivery if needed. A lab test can be done before delivery to check the readiness of the baby’s lungs. When possible, the delivery should be delayed until tests show that the baby’s lungs have matured.
Medicines called corticosteroids may help speed up lung maturity in the developing baby. They are often given to pregnant women between 24 and 34 weeks of pregnancy who seem likely to deliver in the next week. At times it may be possible to give other medicines to delay labor and delivery until the steroid medication has time to work.
This treatment may cut down on the risks from RDS. It may also help prevent other complications from early delivery. However, it will not totally remove the risks.
Martin RJ, Fanaroff AA. The Preterm Lung and Airway: Past, Present, and Future. Pediatr Neonatol. 2013 Mar 31. pii: S1875-9572(13)00036-3.
Kimberly G. Lee, MD, MSc, IBCLC, Associate Professor of Pediatrics, Division of Neonatology, Medical University of South Carolina, Charleston, SC. Review provided by VeriMed Healthcare Network.