Prevention of contrast-induced nephropathy: A randomized controlled trial of sodium bicarbonate and N-acetylcysteine

BACKGROUND: Contrast-induced nephropathy (CIN) continues to be a common cause of acute renal failure in high-risk patients undergoing radiocontrast studies. However, there is still a lack of consensus regarding the most effective measures to prevent CIN. METHODS: One hundred eighteen patients with diabetes mellitus and/or renal insufficiency, scheduled for coronary angiography or intervention, were randomly assigned to one of four treatment groups: intravenous (IV) 0.9% NaCl alone, IV 0.9% NaCl plus N-acetylcysteine (NAC), IV 0.9% sodium bicarbonate (NaHCO₃) alone or IV 0.9% NaHCO₃ plus NAC. All patients received IV hydration as a preprocedure bolus and as maintenance. Iso-osmolar contrast was used in all patients. CIN was defined as an increase of greater than 25% in the serum creatinine concentration from baseline to 72 h. RESULTS: The overall incidence of CIN was 6%. There was no statistically significant difference in the incidence of CIN among the groups. There was a CIN incidence of 7% in the NaCl only group, 5% in the NaCl/NAC group, 11% in the NaHCO₃ only group and 4% in the NaHCO ₃/NAC group (P=0.86). The maximum increase in serum creatinine was 14.14±12.38 mol/L in the NaHCO₃ group, 10.60±29.14 mol/L in the NaCl only group, 9.72±13.26 mol/L in the NaCl/NAC group and 0.177±15.91 mol/L for the NaHCO₃/ NAC group (P=0.0792). CONCLUSION: CIN in high-risk patients may be effectively minimized solely through the use of an aggressive hydration protocol and an iso-osmolar contrast agent. The addition of NaHCO₃ and/or NAC did not have an effect on the incidence of CIN.