From the Guidelines
Preventing contrast-induced nephropathy (CIN) requires a multifaceted approach focused on hydration and risk reduction, with the most effective strategy being intravenous isotonic saline administration at 1-1.5 mL/kg/hour for 6-12 hours before and after contrast exposure, as recommended by the 2014 ESC/EACTS guidelines 1.
Key Recommendations
- Hydration: Intravenous isotonic saline (0.9% sodium chloride) should be administered at 1-1.5 mL/kg/hour for 6-12 hours before and after contrast exposure, with a bolus of 3 mL/kg/hour for 1 hour before contrast and continued at 1-1.5 mL/kg/hour for 6 hours after for urgent procedures.
- Minimizing contrast volume: Use the lowest necessary dose and avoid repeat exposures within 48-72 hours.
- Discontinuing nephrotoxic medications: Discontinue nephrotoxic medications (NSAIDs, aminoglycosides, ACE inhibitors) 24-48 hours before contrast exposure.
- Monitoring renal function: Monitor renal function by checking serum creatinine 48-72 hours after contrast administration.
Additional Considerations
- N-acetylcysteine: The use of N-acetylcysteine is not recommended, as the largest randomized study on N-acetyl-L-cysteine and contrast nephropathy in patients undergoing angiographic procedures, ACT, demonstrated no benefit in primary or secondary endpoints 1.
- Sodium bicarbonate: Sodium bicarbonate administration is not indicated, as the KDIGO guideline recommendation to use either isotonic fluid in high-risk patients is appropriate, and the administration of isotonic saline solution may be preferable in situations where emergent contrast procedures are indicated 1.
Risk Reduction
- Assessing risk: Patients should be assessed for risk of contrast-induced AKI, with underlying impairment in renal function being the principal risk factor.
- Using low-osmolar or iso-osmolar contrast media: Use of low-osmolar or iso-osmolar contrast media is recommended, with the volume of contrast media minimized to prevent contrast-induced AKI in patients undergoing angiography 1.
From the Research
Prevention and Management of Contrast-Induced Nephropathy
- The use of saline hydration is a well-established method for preventing contrast-induced nephropathy (CIN) 2, 3, 4, 5.
- Studies have shown that both intravenous and oral saline hydration can be effective in reducing the incidence of CIN 3.
- The administration of non-ionic isosmolar contrast media, such as iodixanol, can also help to reduce the risk of CIN 2.
- N-acetylcysteine (NAC) has been investigated as a potential preventive agent, but its efficacy is still debated and results are conflicting 2, 4, 5.
- Other pharmacologic agents, such as theophylline and furosemide, have not been shown to be consistently effective in preventing CIN 3, 5.
Risk Factors and Patient Selection
- Patients with preexisting renal insufficiency, diabetes, and high systolic blood pressure are at increased risk of developing CIN 3, 4, 5.
- These high-risk patients may benefit from additional prophylactic measures, such as the use of sarpogrelate, which is currently being investigated in clinical trials 6.
Current Recommendations
- Adequate hydration with saline, using low-osmolar contrast agents, and minimizing the dose of contrast are considered the standard of care for preventing CIN 4, 5.
- Further research is needed to determine the efficacy of other preventive agents and to identify the best strategies for managing CIN in high-risk patients.