Effects of low-dose atrial natriuretic peptide infusion on cardiac surgery–associated acute kidney injury: A multicenter randomized controlled trial

To evaluate the effects of atrial natriuretic peptide (ANP) on renal function and medical costs in patients with acute kidney injury (AKI) associated with cardiac surgery. The Japanese trial for AKI in Post-cardiovascular surgery patients by ANP (JAPAN) was a prospective, multicenter, randomized, double-blind, placebo-controlled study conducted in 11 hospitals in Japan. Acute kidney injury was defined as an increase in serum creatinine of at least 0.3 mg/dL within 48 hours. The patients were randomly assigned to receive ANP (0.02 μg kg−1 min−1) or placebo. The primary end point was a change in renal function. The secondary end points were a need for renal replacement therapy, the lengths of intensive care unit and hospital stays, and medical costs incurred over the 90-day follow-up. Of the 77 randomized patients, 37 were in the ANP group and 40 were in the placebo group. Although ANP significantly (P = .018) increased urine output, it did not significantly improve renal function compared with placebo. There were no significant differences between the groups in the renal replacement therapy rate, the lengths of the intensive care unit and hospital stays, or medical costs. Atrial natriuretic peptide infusion did not show a renoprotective effect or cost-saving effect in the treatment of cardiac surgery–associated AKI.