What is the most appropriate management step for a child with asthma who uses a rescue inhaler weekly?

For a child with asthma who uses a rescue inhaler weekly, the most appropriate management step is the initiation of inhaled fluticasone, which is a corticosteroid. This choice is correct because regular use of a rescue inhaler indicates that the child's asthma is not well controlled, suggesting the need for a preventive treatment strategy. Inhaled corticosteroids are the first-line therapy for long-term asthma management, as they reduce inflammation in the airways, decrease the frequency of asthma attacks, and improve overall lung function.

Inhaled fluticasone will help control the underlying inflammation and allow for better asthma management, potentially decreasing the reliance on rescue inhalers. Inhaled salmeterol, on the other hand, is a long-acting beta-agonist that is typically used in conjunction with inhaled corticosteroids and not as a first-line treatment alone. Repeat spirometry could provide valuable information about pulmonary function but does not directly contribute to management in an acute setting and is not immediately necessary if the patient is symptomatic. Cetirizine, an antihistamine, is not indicated for asthma management and is more suited for controlling allergic symptoms rather than addressing asthma control.