From the FDA Drug Label
- 3 Contrast-Induced Acute Kidney Injury Acute kidney injury, including renal failure, may occur after iodixanol administration Risk factors include: pre-existing renal impairment, dehydration, diabetes mellitus, congestive heart failure, advanced vascular disease, elderly age, concomitant use of nephrotoxic or diuretic medications, multiple myeloma/paraproteinaceous diseases, repetitive and/or large doses of an iodinated contrast agent. Use the lowest necessary dose of iodixanol in patients with renal impairment Adequately hydrate patients prior to and following iodixanol administration. Do not use laxatives, diuretics, or preparatory dehydration prior to iodixanol administration.
The patient has a pre-existing renal impairment with an eGFR of 35 and creatinine level of 113, which increases the risk of contrast-induced acute kidney injury.
- Key considerations for administering contrast in this patient include:
- Using the lowest necessary dose of iodixanol
- Adequate hydration prior to and following administration
- Avoiding laxatives, diuretics, or preparatory dehydration before administration
- Monitoring the patient closely for signs of acute kidney injury after the procedure 1
From the Research
For a 97-year-old lady with an eGFR of 35 and creatinine of 113 μmol/L undergoing CT cholangiogram, I recommend proceeding with a reduced dose of iodinated contrast media at 1.0-1.5 mL/kg, using an iso-osmolar or low-osmolar contrast agent such as iodixanol (Visipaque) or iopamidol (Isovue), as supported by the most recent study 2.
Key Considerations
- The patient's advanced age and moderate renal impairment increase the risk of contrast-induced nephropathy (CIN) 3, 4.
- Iso-osmolar contrast agents, such as iodixanol, cause less renal tubular damage compared to other contrast agents 5, 6.
- Hydration with intravenous normal saline (1 mL/kg/hr for 6 hours before and after the procedure) helps maintain renal perfusion and accelerate contrast excretion 3, 4.
- Temporarily discontinuing nephrotoxic medications (NSAIDs, diuretics, metformin) 24-48 hours before and after the procedure can help minimize CIN risk 4.
Recommendations
- Use a reduced dose of iodinated contrast media at 1.0-1.5 mL/kg.
- Choose an iso-osmolar or low-osmolar contrast agent, such as iodixanol (Visipaque) or iopamidol (Isovue).
- Ensure adequate hydration before and after the procedure with intravenous normal saline.
- Consider prophylactic oral N-acetylcysteine 600 mg twice daily for 24 hours before and after the procedure.
- Monitor renal function by checking creatinine 48-72 hours post-procedure.
- Temporarily discontinue nephrotoxic medications 24-48 hours before and after the procedure. This approach balances diagnostic quality with minimizing contrast-induced nephropathy risk, which is elevated due to her advanced age and moderate renal impairment, as highlighted in the most recent study 2.