What is the nurse's priority action when an older adult client with a known alcohol use disorder presents with acute chest pain in the emergency department?

Rationale: A. Establishing IV access is important in the emergency department for administering medications, fluids, or emergency interventions. However, it is secondary to immediately assessing the patient’s cardiac status. While IV access should be obtained promptly, it is not the first action when a patient presents with acute chest pain, as delays in assessing cardiac function could result in missed life-threatening complications. B. Nitroglycerin is used to treat myocardial ischemia or angina by dilating coronary arteries. Before administering nitroglycerin, the nurse must evaluate blood pressure, heart rate, and ECG findings to ensure the patient is stable and there are no contraindications (e.g., hypotension, recent use of phosphodiesterase inhibitors). Administering nitroglycerin without assessment could precipitate hypotension or worsen ischemia, especially in older adults with comorbidities. C. This is the priority action. Acute chest pain in an older adult, especially with alcohol use disorder (which may contribute to cardiac or electrolyte abnormalities), may signal myocardial infarction, unstable angina, or arrhythmia, all of which are time-sensitive and potentially life-threatening. Vital signs provide immediate information about hemodynamic stability (e.g., blood pressure, heart rate, oxygen saturation), while the ECG can detect ischemic changes, arrhythmias, or infarction. Rapid assessment allows clinicians to initiate evidence-based interventions quickly, such as oxygen, antiplatelet therapy, or advanced cardiac life support if needed. D. While a psychiatric evaluation may be important for addressing alcohol use disorder or related mental health concerns, acute chest pain is a medical emergency that supersedes psychiatric assessment. Delaying cardiac evaluation to address psychiatric needs could result in serious morbidity or death.