An infant is observed with nares flaring and head bobbing during inspiration. Which step in the respiratory assessment is most critical to perform next?

Respiratory assessment in infants requires prompt recognition of signs of increased work of breathing, such as nasal flaring and head bobbing, which indicate respiratory distress. These findings suggest the infant is struggling to maintain adequate ventilation and may have airway obstruction, infection, or lower respiratory pathology. Once distress is identified, the nurse must immediately assess airway function and breath sounds to determine the severity and possible cause. Auscultation provides critical real-time information about airflow and lung involvement. A. Auscultating lung sounds is the most critical next step because it provides immediate information about airway patency and ventilation. Findings such as wheezing, crackles, or diminished breath sounds can help identify conditions like bronchiolitis, pneumonia, or airway obstruction. This assessment guides urgent clinical decision-making and determines whether further interventions are needed. B. Measuring blood glucose levels may be relevant in infants with lethargy or altered consciousness, but it does not address the immediate respiratory distress signs present. Respiratory compromise must be prioritized over metabolic evaluation when there are clear indicators of increased work of breathing. C. Performing a chest X-ray may eventually be required to diagnose conditions such as pneumonia, but it is not the immediate priority. Imaging is a secondary diagnostic tool and should follow rapid bedside assessment and stabilization. The nurse must first evaluate breath sounds before escalating to radiologic studies. D. Conducting an interview about feeding habits is part of a broader history but is not appropriate during acute respiratory distress. Infants showing nasal flaring and head bobbing require immediate physical assessment rather than non-urgent data collection. Delaying respiratory evaluation could worsen outcomes in a potentially unstable infant.