Soru

In early February, the parents of an 18-month-old girl bring her to the emergency department because she has been breathing rapidly and feeding poorly for the past 24 hours. The parents note that her symptoms began four days ago with a runny nose, mild nasal congestion, and a "tight" cough. She has a past medical history of atopic dermatitis managed with emollients. Her immunizations are up to date. Her temperature is 37.9°C (100.2°F), pulse is 158/min, respirations are 58/min, and oxygen saturation is 89% on room air. Physical examination reveals an irritable but consolable toddler with prominent nasal flaring and subcostal retractions. Lung auscultation demonstrates a prolonged expiratory phase, diffuse polyphonic wheezing, and bilateral coarse crackles. A chest radiograph displays bilateral hyperinflation, flattened hemidiaphragms, and a focal, wedge-shaped area of increased opacity in the right middle lobe. Which of the following is the most appropriate next step in management?