Renal Insufficiency After Contrast Media Administration Trial II (REMEDIAL II) RenalGuard System in High-Risk Patients for Contrast-Induced Acute Kidney Injury

Background-The RenalGuard System, which creates high urine output and fluid balancing, may be beneficial in preventing contrast-induced acute kidney injury. Methods and Results-The Renal Insufficiency After Contrast Media Administration Trial II (REMEDIAL II) trial is a randomized, multicenter, investigator-driven trial addressing the prevention of contrast-induced acute kidney injury in high-risk patients. Patients with an estimated glomerular filtration rate <= 30 mL.min(-1).1.73 m(-2) and/or a risk score >= 11 were randomly assigned to sodium bicarbonate solution and N-acetylcysteine (control group) or hydration with saline and N-acetylcysteine controlled by the RenalGuard System and furosemide (RenalGuard group). The primary end point was an increase of >= 0.3 mg/dL in the serum creatinine concentration at 48 hours after the procedure. The secondary end points included serum cystatin C kinetics and rate of in-hospital dialysis. Contrast-induced acute kidney injury occurred in 16 of 146 patients in the RenalGuard group (11%) and in 30 of 146 patients in the control group (20.5%; odds ratio, 0.47; 95% confidence interval, 0.24 to 0.92). There were 142 patients (48.5%) with an estimated glomerular filtration rate <= 30 mL.min(-1).1.73 and 149 patients (51.5%) with only a risk score >= 11. Subgroup analysis according to inclusion criteria showed a similarly lower risk of adverse events (estimated glomerular filtration rate <= 30 mL.min(-1).1.73 m(-2): odds ratio, 0.44; risk score >= 11: odds ratio, 0.45; P for interaction = 0.97). Changes in cystatin C at 24 hours (0.02 +/- 0.32 versus -0.08 +/- 0.26; P = 0.002) and 48 hours (0.12 +/- 0.42 versus 0.03 +/- 0.31; P = 0.001) and the rate of in-hospital dialysis (4.1% versus 0.7%; P = 0.056) were higher in the control group. Conclusion-RenalGuard therapy is superior to sodium bicarbonate and N-acetylcysteine in preventing contrast-induced acute kidney injury in high-risk patients.