1. A patient with chronic heart failure is prescribed a loop diuretic. Which of the following should the nurse prioritize in the patient's care? A. Monitoring serum potassium levels B. Encouraging a high-sodium diet C. Limiting fluid intake to 1 liter per day D. Increasing protein intake Answer: A. Monitoring serum potassium levels Rationale: Loop diuretics can lead to hypokalemia, which can exacerbate heart failure symptoms and lead to dangerous cardiac arrhythmias. 2. A nurse is caring for a patient with type 1 diabetes mellitus. Which of the following actions is essential before administering insulin? A. Checking the patient's blood glucose level B. Providing a carbohydrate-rich snack C. Administering a beta-blocker D. Assessing for signs of ketoacidosis Answer: A. Checking the patient's blood glucose level Rationale: It is crucial to check blood glucose levels to determine the appropriate insulin dose and prevent hypoglycemia. 3. When evaluating a patient's ECG, the nurse notices regular R-R intervals, but no discernible P waves. What is the most likely diagnosis? A. Sinus bradycardia B. Atrial fibrillation C. Ventricular tachycardia D. Atrial flutter Answer: B. Atrial fibrillation Rationale: Atrial fibrillation is characterized by an irregularly