Neonatal Nurse Practitioner Practice Exam

What X-ray finding is confirmatory for meconium aspiration syndrome?

1. Hyperexpansion

2. Peripheral air bronchograms

3. Reticulogranular pattern

4. Atelectasis

The correct answer is: Hyperexpansion

Meconium aspiration syndrome (MAS) occurs when a newborn inhales a mixture of meconium and amniotic fluid into the lungs around the time of birth. The presence of hyperexpansion in the lungs on an X-ray is a key finding that indicates this condition. In MAS, the airways can become obstructed due to the meconium, which leads to areas of trapped air in the lungs, resulting in hyperexpansion or overinflation of the lung fields. This finding is critical as it reflects the changes in lung mechanics due to obstruction and inflammation caused by the aspirated meconium, showcasing the characteristic response of the lungs to the presence of this thick substance. Understanding this radiographic manifestation is essential for diagnosing MAS and differentiating it from other respiratory conditions that may present with different X-ray features.