The primary pulmonary pathophysiological change leading to respiratory distress syndrome (RDS) is:

Neonatal Respiratory Distress Syndrome (RDS) is primarily caused by surfactant deficiency, which results in alveolar collapse and increased permeability of the alveolar-capillary membrane. This leads to pulmonary edema, impaired gas exchange, and hypoxemia.

“The hallmark of RDS is increased permeability of the alveolar-capillary membrane, which allows fluid to leak into alveoli, contributing to atelectasis and reduced oxygenation. Surfactant deficiency is the initiating factor.”

(Referenced from CCRN Pediatric – Direct Care: Pulmonary, Neonatal RDS Pathophysiology)

Increased surfactant production would be protective, not pathological. Pulmonary vascular hypertension can occur secondarily but is not the initiating pathophysiology.