Does prophylactic haemodialysis protect kidney function after angiography?

On the one hand, it is well known that radiocontrast media can effectively be reduced by haemodialysis [1]. On the other hand, several prospective randomized studies clearly demonstrated that prophylactic haemodialysis after the administration of radiocontrast media did not prevent contrastinduced nephropathy and did not improve outcome of patients with chronic kidney disease. Lehnert et al. performed a study in 30 patients with chronic renal failure receiving radiocontrast. Mean baseline serum creatinine concentration was 2.4 mg/dL (212 μmol/L). Patients were randomly assigned to receive either a haemodialysis procedure for 3 h, started as soon as possible after the administration of radiocontrast or a conservative treatment. Contrast-induced nephropathy was not significantly different between the two groups [2]. Vogt et al. performed a randomized trial to test whether radiocontrast nephropathy can be avoided by prophylactic haemodialysis immediately after the administration of radiocontrast in patients with baseline serum creatinine concentrations >2.3 mg/dL (>200 μmol/L). In the haemodialysis group serum creatinine decreased at Day 1, peaked at Day 4 and returned to baseline at Day 6, whereas in the control group no significant changes of serum creatinine concentrations could be observed. Eight patients in the haemodialysis group and three patients in the control group required additional haemodialysis treatments. Therefore, Vogt et al. concluded that the strategy of performing haemodialysis immediately after the administration of lowosmolality radiocontrast media did not diminish the rate of complications, and prophylactic haemodialysis after radiocontrast media in patients with renal insufficiency is potentially harmful [3]. In a prospective, randomized, controlled trial Frank et al. tested the effect of a 4-h online haemodialysis during radiocontrast application in patients with advanced chronic renal failure. Mean baseline creatinine clearance was 18 mL/min. In that study no difference