Purpose: Contrast-induced nephropathy is a complication of contrast medium administration during diagnostic and interventional procedures, with important prognostic relevance. Patients with chronic kidney disease have a higher risk for contrast-induced nephropathy and poorer outcome. In patients with chronic kidney disease, hemofiltration reduces contrast-induced nephropathy incidence and improves long-term survival. We assessed the mechanisms involved in the prophylactic effect of hemofiltration and of the most effective hemofiltration protocol to prevent contrast-induced nephropathy in patients with chronic kidney disease.
Subjects and methods: We randomized 92 patients with chronic kidney disease (creatinine clearance < or =30 mL/min) to three different prophylactic treatments: intravenous hydration with isotonic saline (1 mL x kg x h for 12 hours before and after contrast exposure, control group; n = 30); intravenous hydration for 12 hours before contrast exposure, followed by hemofiltration for 18 to 24 hours after contrast exposure (post-hemofiltration group; n = 31), and hemofiltration performed for 6 hours before and for 18 to 24 hours after contrast exposure (pre/post-hemofiltration group; n = 31). The incidence of contrast-induced nephropathy (>25% increase in creatinine) and the in-hospital clinical course were compared in the three groups.
Results: Twelve patients (40%) in the control group, 8 patients (26%) in the post-hemofiltration group, and 1 patient (3%) in the pre/post-hemofiltration group experienced contrast-induced nephropathy (P = .0013); hemodialysis was required in 9 (30%), three (10%), and zero (0%) patients, respectively (P = .002). In-hospital mortality was 20%, 10%, and 0%, respectively (P = .03).
Conclusions: Hemofiltration is an effective strategy for contrast-induced nephropathy prevention in patients with chronic kidney disease who are undergoing cardiovascular procedures. Pre-hemofiltration is required to obtain the full clinical benefit, suggesting that, among different mechanisms possibly involved, high-volume controlled hydration before contrast media exposure plays a major role.