A term neonate becomes cyanosed soon after birth with right-to-left shunting and persistently high pulmonary vascular resistance after a hypoxic, cold delivery. Which single condition does this represent?

Answer: B. Persistent pulmonary hypertension of the newborn (PPHN)

Persistent pulmonary hypertension of the newborn (PPHN)

PPHN occurs when the normal fall in pulmonary vascular resistance at birth fails to occur or reverses.

Mechanism

• If the physiological changes at birth do not take place, or the neonate is exposed to hypoxia, hypothermia, acidosis or hypovolaemia, the pulmonary vascular resistance stays high.
• This triggers a reversal back toward the fetal pattern, with right-to-left shunting across the foramen ovale, the ductus arteriosus, or both.

Consequence

• Deoxygenated blood bypasses the lungs, causing cyanosis and hypoxaemia, which can be fatal.

Management principles

• Correct the triggers (oxygenation, warmth, acidosis, volume), support ventilation, and use pulmonary vasodilators as needed.

So this cyanotic, high-resistance, right-to-left-shunting picture is PPHN.