A patient is scheduled for CT scan with IV contrast. What should the nurse review in preparation for this test?

Choice A reason: Hemoglobin levels measure the oxygen-carrying capacity of the blood and are useful for identifying anemia or blood loss. However, hemoglobin has no direct interaction with intravenous contrast media and does not provide information regarding the patient's ability to safely process or excrete the contrast dye used in the CT scan. Choice B reason: While "NPO" (nothing by mouth) status is often required for several hours before a scan to prevent aspiration if the patient experiences nausea, it is not as critical a physiological baseline as renal function. Oral intake is a procedural preparation, whereas creatinine is a vital safety assessment for organ function. Choice C reason: Intravenous contrast media is nephrotoxic and can cause contrast-induced nephropathy (CIN), especially in patients with pre-existing renal impairment. Creatinine levels (and the calculated Glomerular Filtration Rate) must be reviewed to ensure the kidneys are capable of filtering the dye; if levels are elevated, the scan may be cancelled or modified. Choice D reason: Blood pressure is a standard vital sign, and while severe hypertension or hypotension should be addressed, it is not a specific screening requirement for IV contrast. The primary systemic risk of contrast media is related to renal damage and anaphylactoid reactions, neither of which are predicted by a baseline blood pressure reading.