What is the typical presentation of persistent fetal circulation?

Persistent fetal circulation, also known as persistent pulmonary hypertension of the newborn (PPHN), typically presents with central cyanosis that is often associated with elevated preductal blood gas values. In this condition, the newborn fails to transition from fetal to neonatal circulation, leading to inadequate oxygenation of the blood. This occurs because the pulmonary vasculature remains constricted, resulting in right-to-left shunting of blood through the ductus arteriosus and foramen ovale instead of being oxygenated in the lungs.

Central cyanosis is a hallmark of this condition due to systemic hypoxia, and the high preductal blood gas indicates that the blood is not being effectively oxygenated before reaching the systemic circulation. This finding helps distinguish it from other presentations and confirms that oxygenated blood is not adequately reaching the aorta.

In contrast to other choices, the lack of adequate oxygenation and the specific changes observed in the blood gas levels are what characterize persistent fetal circulation, making the identification of central cyanosis and high preductal blood gas values crucial for diagnosis and management.