A client with chronic heart failure (HF), who is experiencing dyspnea and peripheral edema, is receiving digoxin and furosemide. Which observation indicates to the nurse that these medications are effective? Reference Range: Potassium (K+) [3.5 to 5 mEq/L (3.5 to 5 mmol/L)]

Rationale: A. Serum potassium is 4 mEq/L (4 mmol/L): A potassium level within the normal range is important to monitor. However, this lab value reflects safety rather than the effectiveness of therapy in improving heart failure symptoms. B. Heart rate is 74 beats/minute and regular: Digoxin helps control heart rate and improve contractility, so a normal, regular pulse is a positive finding. Still, this does not directly confirm that the client’s heart failure symptoms such as edema and dyspnea are being relieved. C. Weight has decreased in one day: Furosemide reduces fluid overload by promoting diuresis, and weight loss over a short period reflects decreased fluid retention. This directly shows improvement in heart failure symptoms like edema and dyspnea. D. Intake is greater than the output: This suggests fluid retention, which is a negative finding in heart failure management. Effective treatment would result in output exceeding or at least balancing intake as diuresis occurs.