Prevention of contrast media-induced nephropathy by isotonic sodium bicarbonate: a meta-analysis

The clinical value of hydration therapy using sodium bicarbonate in the prevention of contrast media-induced nephropathy is subject of controversy.

This meta-analysis of randomized clinical trials was performed to determine whether hydration therapy using sodium bicarbonate consistently differs from control hydration regimens with normal saline in its preventive effects upon radiocontrast media-induced renal dysfunction.

Randomized clinical trials comparing sodium bicarbonate with a control regimen for prevention of contrast media-induced nephropathy were selected by multiple methods, including computer searches of bibliographic databases, perusal of reference lists, and manual searching. Major findings were qualitatively summarized. In addition, a quantitative meta-analysis was performed on renal dysfunction data.

Altogether, 9 randomized clinical trials with a total of 2,043 patients were included. The pooled odds ratio was 0.45 (confidence interval, 0.26-0.79), indicating a significant treatment benefit of sodium bicarbonate compared to normal saline. Heterogeneity was detectable (p=0.016) and evidence of publication bias was present (p=0.012). After adjustment for presumed unpublished trials after trim-and-fill analysis, the estimated pooled odds ratio was 0.65 (confidence interval, 0.36-1.20).

This meta-analysis confirms that, based on currently available randomized trials, bicarbonate therapy is effective in preventing contrast media-induced nephropathy. However, study heterogeneity and publication bias are substantial, and therefore further controlled clinical trials are needed.