A 4-year-old child with a history of cystic fibrosis (CF) presents to the clinic for a routine follow-up. The parents report that the child has had an increase in productive cough, wheezing, and shortness of breath over the past few days. Upon examination, the child has clubbed fingers, and chest auscultation reveals decreased breath sounds. Given these findings, which of the following interventions should the nurse prioritize to manage the child's condition and prevent further respiratory complications?