Extracorporeal blood purification therapies for prevention of radiocontrast-induced nephropathy: a systematic review.

BACKGROUND Radiocontrast-induced nephropathy (RCIN) causes acute kidney injury and increases mortality. Studies have examined the capacity of various forms of extracorporeal blood purification therapies for the prevention of RCIN, with conflicting results. We conducted a systematic review of published trials to determine whether periprocedural extracorporeal blood purification prevents RCIN. METHODS We searched PubMed, the Cochrane Collaboration Database, EMBASE, and CINAHL through January 2006 and bibliographies of retrieved articles and consulted with experts to identify relevant studies. Published studies of extracorporeal blood purification for the prevention of RCIN in patients receiving radiocontrast were included. Two authors reviewed all citations. The primary end point is the incidence of RCIN, defined as an increase in serum creatinine concentration (>or=0.5 mg/dL [>or=44 micromol/L]). Results were combined on the risk ratio scale. Random-effects models were used. Sensitivity analyses were performed to evaluate the effects of extracorporeal blood purification modality, study design, and sample size. RESULTS Eight trials (6 randomized controlled trials, 2 nonrandomized trials) were included in the analysis (pooled sample size, 412). Six trials assessed hemodialysis, whereas 1 trial each assessed continuous venovenous hemofiltration and continuous venovenous hemodiafiltration. The incidence of RCIN was 35.2% in the standard-medical-therapy group and 27.8% in the extracorporeal-blood-purification group. Extracorporeal blood purification did not decrease the incidence of RCIN significantly compared with standard medical therapy (risk ratio, 0.97; 95% confidence interval, 0.44 to 2.14); however, intertrial heterogeneity was high. Limiting analysis to only randomized trials did not eliminate heterogeneity, but limiting analysis to only hemodialysis trials did. Periprocedural hemodialysis did not decrease the incidence of RCIN. CONCLUSION This critical analysis of the published literature suggests that periprocedural extracorporeal blood purification does not decrease the incidence of RCIN compared with standard medical therapy.