A 3-year-old boy is brought to the emergency department by his mother with a 6-hour history of sudden-onset coughing and difficulty breathing after playing with peanuts. On examination, he is in mild respiratory distress with stridor. Chest auscultation reveals decreased air entry on the right side with occasional wheezing. Anteroposterior and lateral neck radiographs show no radiopaque foreign body. What is the most appropriate next step in management?