A nurse is collecting data from a client who has pneumonia and reports shortness of breath. The nurse notes the client has crackles auscultated in the lower lobes and an SaO2 of 88% on room air. Which of the following actions should the nurse take first?

A. Assist the client to cough and deep breathe: Encouraging coughing and deep breathing helps mobilize secretions and improve alveolar ventilation. While this is an important intervention for pneumonia, it does not immediately address the client’s current hypoxemia, which requires rapid intervention to improve oxygenation. B. Administer scheduled antibiotic medication: Antibiotics are essential to treat the underlying infection, but their effect is not immediate. They do not correct acute hypoxemia or respiratory distress, so administering the antibiotic is not the first priority in this situation. C. Discuss the pneumococcal vaccine with the provider: Vaccination is a preventive measure to reduce the risk of future infections. It does not address the acute hypoxemia or impaired gas exchange the client is experiencing during the current episode of pneumonia. D. Position the client in high-Fowler's position: Elevating the client to a high-Fowler’s position promotes maximal lung expansion and improves ventilation-perfusion matching. This immediate intervention helps increase oxygen saturation and ease shortness of breath, making it the priority action in a client with SaO2 of 88% on room air.