After an older client receives treatment for drug toxicity, the healthcare provider prescribes a 24-hour creatinine clearance test. Prior to starting the urine collection, the nurse notes that the client's serum creatinine is 0.3 mg/dL (22.9 μmol/L). Which action should the nurse implement? Creatinine [Reference Range: 0.5 to 1.1 mg/dL (44 to 97 μmol/L)]