A nurse is caring for a client who suddenly develops chest pain and dyspnea. Which of the following actions should the nurse take first?

Sudden onset chest pain and dyspnea is an emergency presentation that may indicate life-threatening conditions such as pulmonary embolism, acute coronary syndrome, or acute respiratory compromise. In such situations, nursing care follows the priority principle of ABCs (airway, breathing, circulation), with immediate interventions aimed at improving oxygenation. Rapid positioning and respiratory support are essential before diagnostic tests or advanced interventions are performed. The nurse must optimize breathing and reduce work of respiration. Rationale: A. Obtaining arterial blood gas (ABG) levels is important for evaluating oxygenation and acid-base status, but it is not the first priority. Diagnostic tests do not take precedence over immediate interventions that support breathing. The nurse must first stabilize the patient’s respiratory status before collecting laboratory data. B. Placing the client on bedrest is not an immediate priority intervention in acute respiratory distress. While reducing activity is appropriate, it does not directly improve oxygenation or ventilation. The urgent concern is enhancing respiratory function, not simply limiting movement. C. Preparing the client for a ventilation-perfusion (V/Q) scan is a diagnostic step used to confirm conditions such as pulmonary embolism. However, it is not an immediate life-saving intervention. Stabilization of airway and breathing must occur before transporting or preparing the client for imaging studies. D. Elevating the head of the bed is the priority action because it promotes optimal lung expansion and improves oxygenation. This position reduces diaphragmatic pressure from abdominal organs and decreases work of breathing. It also enhances ventilation-perfusion matching and helps relieve dyspnea, making it the first nursing intervention.