What physiologic abnormality is believed to be the cause of persistent pulmonary hypertension in the newborn (PPHN)?

Question

Quizplus · Accepted Answer

PPHN is caused by high pulmonary vascular resistance, which leads to decreased blood flow to the lungs and increased pressure in the pulmonary arteries. This can result in a right-to-left shunt, but the underlying physiological abnormality is the high pulmonary vascular resistance. High cardiac output and metabolic acidosis can occur as a result of the pulmonary hypertension, but they are not the underlying cause.

What Physiologic Abnormality Is Believed to Be the Cause of Persistent