In assessing a 2-year-old boy with croup, the practical nurse (PN) finds that he has become increasingly irritable and has developed tachypnea and resting stridor. Which intervention is best for the PN to implement?

Croup is a respiratory infection that causes inflammation and narrowing of the airway, resulting in a barking cough, hoarseness, and stridor. The PN should monitor the child's oxygen saturation level via pulse oximetry, as it can indicate the severity of the airway obstruction and the need for supplemental oxygen or other interventions.