Question

What is the sequence of events leading to infant respiratory distress syndrome?

a. Surfactant production, alveolar collapse, and increased compliance

b. Premature birth, insufficient surfactant, and alveolar collapse

c. Increased lung compliance, surfactant deficiency, and bronchoconstriction

d. Maternal infection, fetal hypoxia, and decreased lung compliance

Answer 1

The correct sequence leading to infant respiratory distress syndrome (IRDS) is premature birth, leading to insufficient production of pulmonary surfactant and subsequent alveolar collapse, impairing gas exchange and causing respiratory difficulties.

Step-by-step explanation:

The sequence of events leading to infant respiratory distress syndrome (IRDS) begins with premature birth. Infants born prematurely, especially before 28 weeks of gestation, often have not developed sufficient amounts of pulmonary surfactant. Surfactant is crucial for reducing the surface tension within the alveoli, the tiny air sacs in the lungs, and for keeping them open. Without enough surfactant, the alveoli collapse, making it difficult for the infant to inflate their lungs and engage in normal breathing. This alveolar collapse leads to difficulty in gas exchange, resulting in low blood oxygen levels (hypoxia) and high levels of carbon dioxide (hypercapnia), the latter contributing to respiratory acidosis. Because of the importance of surfactant in lung function, therapies for IRDS often involve administering pulmonary surfactant and supporting the infant with respiratory aids such as ventilators or continuous positive airway pressure (CPAP) machines.