Cruz DN et al. (2006) Extracorporeal blood purification therapies for prevention of radiocontrast-induced nephropathy: a systematic review. Am J Kidney Dis 48: 361–371

Radiocontrast-induced nephropathy (RCIN) is a primary cause of hospital-acquired acute renal injury. Excretion of radiocontrast agent from the kidneys is delayed in patients with underlying renal disease. It has been proposed that improving clearance through treatment with extracorporeal blood purification (EBP) could prevent RCIN, but trial data are conflicting.

Cruz et al. systematically reviewed available literature through a search of PubMed, the Cochrane Collaboration Database, EMBASE and CINAHL, as well as reviewing retrieved bibliographies and consulting experts. They identified six randomized controlled trials and two nonrandomized trials comparing EBP with standard therapy (n = 412)—six used hemodialysis, one continuous venovenous hemofiltration, and one continuous venovenous hemodiafiltration, immediately before, during, or within 2 h of administration of contrast agents. RCIN incidence, defined as an increase in serum creatinine concentration of at least 0.5 mg/dl (44 μmol/l), was 35.2% with standard medical therapy (e.g. saline, calcium channel blockers, aminophylline), and 27.8% with EBP. RCIN incidence was not significantly reduced with EBP compared with standard therapy, but the results of the trials were heterogeneous. When only trials studying hemodialysis were included, there was a nonsignificant trend favoring standard therapies over periprocedural EBP. Form of periprocedural treatment did not markedly affect the need for acute temporary renal replacement therapy, or the combined incidence of death and/or the need for permanent renal replacement therapy.

Additional studies with alternative endpoints and investigating newer techniques are warranted, but these results indicate that periprocedural EBP does not decrease RCIN incidence compared with standard medical therapy.