From the Guidelines
Respiratory Distress Syndrome (RDS) is primarily caused by insufficient production of surfactant in premature infants, leading to increased surface tension in the alveoli and difficulty breathing. The condition is characterized by inflammatory pulmonary edema resulting in severe hypoxemia, as noted in the American Thoracic Society's clinical practice guideline 1. According to the Berlin Definition, ARDS is defined as the presence of acute arterial hypoxemia with a minimum requirement of 5 cmH2O positive end-expiratory pressure (PEEP) and bilateral radiographic opacities not entirely explained by cardiac failure or fluid overload 1.
Key Factors Contributing to RDS
- Insufficient surfactant production
- Inflammatory pulmonary edema
- Severe hypoxemia
- Premature birth
The provided evidence primarily discusses Acute Respiratory Distress Syndrome (ARDS) in adults, which has different underlying causes and mechanisms compared to RDS in premature infants. However, the fundamental issue of surfactant deficiency and the resulting increase in surface tension within the lungs is a common thread. In adults, ARDS can result from various insults, including pneumonia, sepsis, and trauma, leading to an inflammatory response and pulmonary edema 1.
Management and Treatment
Treatment for RDS in premature infants typically involves:
- Supplemental oxygen
- Mechanical ventilation if needed
- Surfactant replacement therapy with medications like beractant, poractant alfa, or calfactant
- Continuous positive airway pressure (CPAP) for less severe cases
- Supportive care including proper fluid balance, nutrition, and temperature regulation
- Prevention strategies such as administering corticosteroids to mothers at risk of preterm delivery to accelerate fetal lung maturation.
Given the focus on morbidity, mortality, and quality of life, the most critical aspect of managing RDS is early intervention with surfactant replacement therapy and supportive care to reduce the risk of complications and improve outcomes. While the evidence provided does not directly address RDS in premature infants, the principles of managing respiratory distress by addressing the underlying cause, whether it be surfactant deficiency or inflammatory pulmonary edema, remain crucial 1.
From the FDA Drug Label
Endogenous pulmonary surfactant reduces surface tension at the air-liquid interface of the alveoli during ventilation and stabilizes the alveoli against collapse at resting transpulmonary pressures A deficiency of pulmonary surfactant in preterm infants results in Respiratory Distress Syndrome (RDS) characterized by poor lung expansion, inadequate gas exchange, and a gradual collapse of the lungs (atelectasis). Deficiency of pulmonary surfactant causes Respiratory Distress Syndrome (RDS) in premature infants.
The cause of Respiratory Distress Syndrome (RDS) is a deficiency of pulmonary surfactant in preterm infants, which leads to poor lung expansion, inadequate gas exchange, and a gradual collapse of the lungs (atelectasis) 2, 2, 3.
- Key factors:
- Surfactant deficiency: Lack of pulmonary surfactant in preterm infants
- Preterm infants: Increased risk of RDS due to surfactant deficiency
- Poor lung expansion: Inadequate gas exchange and lung collapse (atelectasis) result from surfactant deficiency
From the Research
Causes of Respiratory Distress Syndrome (RDS)
- RDS is caused by a deficiency of surfactant in the lungs, which can lead to respiratory failure in preterm infants 4.
- The risk factors for the development of ARDS, a similar condition, include trauma, multiple blood transfusions, burns, and major surgery 5.
- Surfactant deficiency is the major cause of RDS, and surfactant therapy has been shown to significantly decrease air leaks and neonatal and infant mortality 6, 4.
Pathophysiology of RDS
- RDS is characterized by inflammatory lung injury, which can result in refractory and life-threatening hypoxaemic respiratory failure 7, 5.
- The condition is associated with high short-term mortality rates and significant long-term consequences among survivors 7.
- The goals of supportive care, principally with mechanical ventilation, have changed in recent years to focus on avoiding ventilator-induced lung injury while providing adequate gas exchange 7.
Treatment and Management of RDS
- Surfactant therapy is a standard care for infants with or at risk for RDS, and has been shown to decrease air leaks, neonatal and infant mortality, as well as cost among survivors 6.
- Natural surfactants derived from animal sources have been shown to be more effective than synthetic surfactants in treating RDS 6, 4.
- Adjunctive therapies, such as pharmacologic techniques and nonpharmacologic techniques, may also be used to support patients with ARDS 7.