Which of the following describes a barrel-chested appearance in a newborn?

A barrel-chested appearance in a newborn is often indicative of airway obstruction or compromised lung function. When a newborn experiences meconium aspiration syndrome, it results from the inhalation of meconium-stained amniotic fluid into the lungs, which can lead to increased pressure and limited lung expansion. This condition affects breathing patterns and can cause the chest to appear barrel-shaped due to the combination of hyperinflation and airway resistance.

This appearance may also be a response to the infant’s effort to breathe in the face of compromised lung function. The other conditions listed—normal lung development, pneumonia, and bronchitis—do not typically lead to the characteristic barrel-chest shape associated with meconium aspiration. Normal lung development would show a more conventional chest shape, pneumonia generally leads to consolidation and discomfort rather than a barrel shape, and bronchitis is less common in newborns and typically does not present with this specific physical characteristic.