Respiratory Distress Syndrome (RDS) is a serious breathing disorder affecting newborns, primarily premature infants. The condition develops when a baby’s lungs are not fully mature, causing difficulty breathing immediately or shortly after birth. RDS is a common diagnosis in neonatal intensive care units (NICUs) and remains a leading cause of illness and death among infants born early. Advances in medical care have dramatically improved outcomes for infants with RDS. Understanding the cause, identifying susceptible infants, and knowing the current treatments are important for families facing this diagnosis.
The Underlying Cause of Respiratory Distress Syndrome
The direct cause of Respiratory Distress Syndrome is an insufficient amount of pulmonary surfactant in the baby’s lungs. Surfactant is a complex mix of lipoproteins and phospholipids that reduces surface tension inside the tiny air sacs, called alveoli. This function prevents the alveoli from completely collapsing when the infant exhales.
Without enough surfactant, the lungs become stiff and require effort to inflate, a condition known as reduced lung compliance. This leads to widespread collapse of the air sacs (atelectasis), which prevents proper oxygen and carbon dioxide exchange. The strain on the infant’s body to keep the lungs open results in respiratory failure.
Identifying Those Most at Risk
The most significant factor determining an infant’s risk for RDS is gestational age at birth; the earlier the delivery, the higher the likelihood and severity of the condition. For example, nearly all babies born at 24 weeks gestation will develop RDS, but the risk drops for those born closer to full-term. Lung maturity and surfactant production typically increase rapidly between 34 and 37 weeks of pregnancy.
Beyond prematurity, several other factors increase susceptibility to RDS. Infants born to mothers with poorly controlled diabetes are at elevated risk because high insulin levels can slow surfactant production. A delivery by Cesarean section without the onset of labor can also increase risk, as the stress of labor helps trigger hormones that accelerate lung maturity. Other risk factors include being male, having a sibling with RDS, or being part of a multiple birth.
Diagnosis
Diagnosis is confirmed by observing characteristic clinical signs that often appear within the first few hours after birth. These signs include tachypnea (rapid breathing), grunting sounds on exhalation, and cyanosis (a bluish tint to the skin due to low oxygen). Diagnostic tools support the diagnosis, such as a chest X-ray, which typically shows a diffuse “ground glass” appearance due to the widespread collapse of the alveoli. Blood gas analysis is also performed to measure oxygen and carbon dioxide levels, indicating the degree of respiratory failure.
Current Medical Management
Intervention focuses on supporting breathing while the baby’s lungs mature and produce their own surfactant. Exogenous surfactant therapy directly addresses the underlying deficiency. This treatment involves administering a synthetic or animal-derived surfactant preparation directly into the baby’s windpipe through a small tube.
Surfactant replacement therapy decreases the surface tension in the alveoli, making it easier for the baby to breathe and reducing the severity of RDS. Following administration, infants are typically placed on respiratory support to aid the surfactant’s effectiveness.
Respiratory support starts with non-invasive methods like Continuous Positive Airway Pressure (CPAP). CPAP delivers pressurized air through nasal prongs to keep the airways and alveoli open without intubation. For more severe cases, mechanical ventilation is used, where a machine breathes for the infant, ensuring consistent oxygen delivery and carbon dioxide removal.
Preventative measures accelerate fetal lung development before birth. Antenatal corticosteroids, such as betamethasone, are given by injection to the mother, usually between 24 and 34 weeks of gestation. These steroids cross the placenta and stimulate the baby’s lungs to produce and release surfactant, reducing the chances of severe RDS.
Recovery and Long-Term Health
The recovery phase for infants with Respiratory Distress Syndrome depends on the severity of the initial illness and the required treatment. Most infants recover completely as their lungs mature. However, infants who experience the most severe forms of RDS and require prolonged respiratory support may face complex outcomes.
The primary long-term complication associated with severe RDS and its treatment is Bronchopulmonary Dysplasia (BPD), a form of chronic lung disease. BPD involves structural changes to the developing lung tissue resulting from prematurity, oxygen exposure, and mechanical ventilation. Infants with BPD may require continued oxygen support and medications for months, and they are more susceptible to respiratory infections.
Infants with a history of severe RDS, especially those with BPD, may have an increased risk of neurodevelopmental delays. These delays are often linked to the underlying prematurity and associated complications, such as intraventricular hemorrhage, rather than RDS itself. Comprehensive follow-up programs monitor these infants to ensure they receive early intervention services, which improve long-term outcomes.