Thursday February 7, 2008
Sodium Bicarbonate in contrast induced nephropathy (CIN) - a risk ?


Sodium Bicarbonate is increasingly being used to prevent contrast induced nephropathy which was based on a small study (1). The role of this prophylaxis is being questioned by a recent large retrospective study from Mayo (2).

Groups:

1. sodium bicarbonate,
2. N-acetylcysteine, and
3. the combination of sodium bicarbonate with N-acetylcysteine

Contrast nephropathy was defined as postexposure creatinine elevation of 25% or >0.5 mg/dl within 7 days of contrast exposure.

Total numbers:

• A total of 11,516 contrast exposures in 7977 patients had creatinine values available for review before and after contrast exposure.
• Sodium bicarbonate was used in 268 cases,
• N-acetylcysteine was used in 616 cases, and
• both agents were used in combination in 221 cases
  

Results:

• Use of sodium bicarbonate alone was associated with an increased risk of contrast nephropathy compared with no treatment
• N-acetylcysteine alone and in combination with sodium bicarbonate was not associated with any significant difference in the incidence of contrast nephropathy.
  
  

Conclusions: The use of intravenous sodium bicarbonate was associated with increased incidence of contrast nephropathy.

But also note, recent REMEDIAL trial, showed that the strategy of volume supplementation by sodium bicarbonate plus NAC seems to be superior to the combination of normal saline with NAC in preventing CIN in patients at medium to high risk. (3)


Editors' note: So far, it appears except for adequate hydration, most of the therapies have no consistent track of advantage and results are variable.

References: click to get abstract/article

1. Prevention of contrast-induced nephropathy with sodium bicarbonate: A randomized controlled trial. JAMA 2004; 291:2328-2334.

2. Sodium bicarbonate is associated with an increased incidence of contrast nephropathy: A retrospective cohort study of 7977 patients at Mayo Clinic. Clin J Am Soc Nephrol 2008; 3:10-18.

3. Renal Insufficiency Following Contrast Media Administration Trial (REMEDIAL). A randomized comparison of 3 preventive strategies. Circulation 2007; DOI:10.1161/CIRCULATIONAHA.106.687152.