From the Guidelines
Patients with a kidney transplant undergoing a procedure with contrast media should receive adequate preparatory hydration, have their renal function assessed, and the volume of contrast media minimized to reduce the risk of contrast-induced acute kidney injury (AKI) 1. To prepare a kidney transplant patient for a procedure with contrast media, several steps should be taken to minimize the risk of AKI and protect the transplanted kidney.
- Assess the patient's current renal function with recent creatinine and estimated glomerular filtration rate (eGFR) values to determine the baseline kidney function 1.
- Ensure adequate hydration with intravenous normal saline (1 mL/kg/hr) for 6-12 hours before and after the procedure to reduce the risk of contrast-induced AKI 1.
- Temporarily hold potentially nephrotoxic medications, including NSAIDs, ACE inhibitors, ARBs, and metformin, for 24-48 hours before and after contrast exposure to minimize the risk of kidney damage 1.
- Consider using the lowest possible dose of iso-osmolar or low-osmolar contrast media to reduce the risk of contrast-induced AKI 1.
- Monitor renal function with creatinine measurements at 24-48 hours post-procedure to assess for any changes in kidney function 1. It is also important to note that administration of N-acetyl-L-cysteine is not useful for the prevention of contrast-induced AKI, according to the 2011 ACCF/AHA/SCAI guideline 1. Additionally, patients with prior evidence of an anaphylactoid reaction to contrast media should receive appropriate prophylaxis before repeat contrast administration 1. By taking these precautions, the risk of AKI and other complications can be minimized, and the transplanted kidney can be protected.
From the Research
Preparations for Patients with Kidney Transplant Undergoing Procedures with Contrast Media
To minimize the risk of contrast-induced nephropathy (CIN) in patients with a kidney transplant, several preparations are necessary:
- Identification of patients at risk: This can be done through patient questionnaires, review of medical history, and measurement of serum creatinine levels prior to the administration of contrast media 2.
- Hydration: Patients should be well-hydrated, and intravenous hydration should be started 12 hours pre-procedure up until 12-24 hours after the procedure, especially in patients with an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 3.
- Nephrotoxic medications: These should be withdrawn at least 24 hours prior to contrast media administration 2.
- Selection of contrast media: The use of low or iso-osmolar contrast media is recommended, and the volume of contrast media should be limited to eGFR x 3.7 3.
- Pharmacological intervention: The use of N-acetylcysteine has been studied, but its effectiveness in preventing CIN is inconsistent, with some studies showing a beneficial effect 4 and others showing no effect 5, 6.
- Other strategies: Additional contrast-sparing strategies may be applied, such as using a contrast reduction system, 5 Fr catheter with no sideholes, contrast media dilution, limiting test injection, confirming placement using guidewire, use of stent enhancing imaging technology, using metallic/software roadmap to guide PCI, use of IVUS or dextran-based OCT, and coronary aspiration 3.