N-acetylcysteine and fenoldopam protect the renal function of patients with chronic renal insufficiency undergoing cardiac surgery

Objective: To determine whether fenoldopam and N-acetylcysteine prevent renal deterioration and improve hospital outcome for patients with chronic renal insufficiency undergoing cardiac surgery. Design: Prospective, randomized, double-blinded, placebocontrolled trial. Setting: A community hospital that is a cardiac referral center. Patients: Seventy-nine adult patients with chronic renal insufficiency (creatinine clearance <= 40 mL/min). who underwent cardiac surgery. Interventions: Group 1 received intravenous fenoldopam 0.1 mu g/kg/min started at surgical induction and continued for 48 hrs. Group 2 received N-acetylcysteine 600 mg orally twice a day, from preoperative day 1 to postoperative day 1. Group 3 received both fenoldopam and N-acetylcysteine, and group 4 patients served as controls. Measurements and Main Results: Using multiple comparisons (analysis of variance) with change scores, and statistically adjusting for group differences in aortic cross-clamp time, use of intraoperative aprotinin, and preoperative use of statin, we found that the change in creatinine clearance from preoperative to postoperative day 3 was statistically less for group 1 (-1.47 mL/min +/- 2.06 SE, p =.0286) and for group 2 (- 0.67 mL/min +/- 2.11 SE, P =.0198) and less but not quite significant for group 3 (-3.08 mL/min +/- 1.95 SE, p =.0891) compared with controls (-8.15 mL/min +/- 2.18 SE). Furthermore, the adjusted weight gain on postoperative day 3 was 5.55 kg +/- 1.00 SE (P =.0988) for group 1, 5.06 kg +/- 1.06 SE (P =.0631) for group 2, and 5.14 kg +/- .91 SE (p =.0445) for group 3 compared with 8.03 kg +/- 1.07 SE for group 4. However, there was no decrease in length of critical care or hospital stay or hospital costs. Finally, fenoldopam contributed to perioperative hypotension. Conclusions: Perioperative fenoldopam and N-acetylcysteine abrogate the early postoperative decline in renal function of patients who have chronic renal insufficiency, although these agents do not affect other parameters of cardiac surgical outcome.