Patients with chronic heart failure on loop diuretics are at risk for which complication?

• A. Hyperkalemia
• B. Hypermagnesemia
• C. Hypoglycemia
• D. Azotemia

Answer: (D)

Loop diuretics reduce intravascular volume, which can drop renal perfusion especially in chronic heart failure where kidney blood flow is already compromised. This can lead to prerenal azotemia, reflected by an elevation in BUN relative to creatinine, making azotemia the most likely complication in this setting. While diuretics commonly cause electrolyte shifts such as hypokalemia and hypomagnesemia, they do not typically cause hyperkalemia or hypermagnesemia, and hypoglycemia is not a typical direct effect. Monitoring kidney function and adjusting diuretic therapy helps prevent or manage azotemia.