Inpatient Obstetric Nurse (NCC) Practice Exam

Newborns with acyanotic defects typically display a "pink" appearance because these conditions allow for the shunting of oxygenated blood to flow into systemic circulation effectively. In acyanotic heart defects, there is usually a left-to-right shunt, where oxygen-rich blood from the left side of the heart flows back to the right side, leading to an adequate level of oxygenation in the arterial blood. This results in the absence of significant cyanosis, which is a bluish discoloration associated with low oxygen saturation.

In contrast, cyanotic defects lead to right-to-left shunting, which decreases oxygen saturation and results in a bluish appearance of the skin and mucous membranes due to hypoxemia. Obstructive defects can vary widely in presentation, but they often involve issues that may not specifically result in a noticeably "pink" appearance. Therefore, acyanotic defects being associated with effective oxygenation contributes to the characteristic "pink" appearance in these newborns.