Surfactant Inactivation in Newborns: Can You Crack This Tricky Neonatal Case? 🧠

追加: 2026-05-17

[00:00:00]Case 10, surfactant inactivation. A 39-week newborn with meconium aspiration syndrome is intubated in the neonatal intensive care unit. Laboratory analysis of tracheal aspirate reveals high concentrations of free fatty acids and proteolytic enzymes from meconium. The surfactant to albumin ratio is significantly reduced compared to normal values. Pulmonary function testing shows increased surface tension and progressive alveolar collapse. What is the primary consequence of surfactant inactivation in meconium aspiration syndrome? Option A, increased lung compliance. Option B, decreased functional residual capacity. Option C, improved ventilation perfusion matching.

[00:00:40]Option D, enhanced oxygen diffusion across the alveolar membrane. The correct answer is option B, decreased functional residual capacity. The surfactant inactivation mechanism works as follows. Meconium contains free fatty acids and proteolytic enzymes that directly inactivate pulmonary surfactant. Loss of surfactant increases alveolar surface tension, which leads to alveolar collapse, and the result is decreased functional residual capacity.

[00:01:06]A critical clinical impact, surfactant dysfunction reduces lung compliance by up to 40% in severe cases. The