Final answer:
The nurse would monitor serum creatinine to determine a patient's kidney function.
Step-by-step explanation:
The laboratory result that the nurse would monitor to best determine a patient's kidney function is serum creatinine.
The level of serum creatinine in the blood is an indicator of kidney function. Creatinine is a waste product that is filtered out of the blood by the kidneys, so a high level of serum creatinine suggests that the kidneys are not functioning properly.
If the nurse finds an elevated serum creatinine level, further tests may be done to determine the cause and level of decline in kidney function.