Final Answer:
In NRDS, hypoxemia is most commonly caused by a deficiency of pulmonary surfactant in premature infants, resulting in difficulty maintaining lung expansion and oxygenation. Treatment often involves administering artificial surfactant and supportive measures.
Step-by-step explanation:
NRDS (Neonatal Respiratory Distress Syndrome), also known as infant respiratory distress syndrome (IRDS), is commonly caused by a deficiency of pulmonary surfactant in premature infants. Surfactant is a substance that helps keep the air sacs in the lungs (alveoli) open, preventing them from collapsing.
In premature infants, particularly those born before 28 weeks of gestation, the lungs may not have produced enough surfactant, leading to increased surface tension and difficulty in maintaining lung expansion. This can result in hypoxemia (low oxygen levels) and respiratory distress. The administration of artificial surfactant and other supportive measures is often used to manage NRDS in premature infants.