A patient is admitted to the hospital with a diagnosis of methicillin-resistant Staphylococcus aureus (MRSA) infection and is receiving intravenous vancomycin. Which laboratory test should the nurse expect the healthcare provider to order to monitor the safety of this medication?

A. Serum creatinine level: Vancomycin is nephrotoxic, especially with prolonged therapy or high serum levels. Monitoring serum creatinine evaluates kidney function and helps detect early signs of renal impairment. Renal monitoring is essential to ensure safe dosing and prevent toxicity. B. Complete blood count: A complete blood count may be monitored for overall infection response, but it does not specifically assess vancomycin toxicity. CBC changes are not the primary safety concern associated with this medication. C. Serum potassium level: Vancomycin does not typically cause significant potassium imbalances. Potassium monitoring is not routinely required unless the patient has other risk factors or is receiving additional nephrotoxic or potassium-altering medications. D. Serum glucose level: Vancomycin does not directly affect blood glucose levels. Glucose monitoring would only be indicated if the patient has diabetes or another condition affecting glucose regulation.