OBJECTIVES Prophylactic acetylcysteine along with hydration seems to be better than hydration alone in preventing the reduction in renal function induced by a contrast dye. BACKGROUND Contrast media can lead to acute renal failure that may occasionally require hemodialysis. METHODS One hundred eighty-three consecutive patients with impairment of renal function, undergoing coronary and/or peripheral angiography and/or angioplasty, were randomly assigned to receive 0.45% saline intravenously and acetylcysteine (600 mg orally twice daily; group A, n = 92) or 0.45% saline intravenously alone (group B, n = 91) before and after nonionic, low-osmolality contrast dye administration. RESULTS The baseline serum creatinine concentrations were similar (1.5 +/- 0.4 mg/dl in group A vs. 1.5 +/- 0.4 mg/dl in group B; p = 0.37). An increase of greater than or equal to25% in the baseline creatinine level 48 h after the procedure occurred in 6 (6.5%) of 92 patients in group A and in 10 (11%) of 91 patients in group B (p = 0.22). In the subgroup with a low (<140 ml) contrast dose, renal function deterioration occurred in 5 (8.5%) of 60 patients in group B and in 0 of 60 patients in group A (p - 0.02; odds ratio [OR] 0.44, 95% confidence interval [CI] 0.35 to 0.54). In the subgroup with a high contrast dose, no difference was found (5/31 vs. 6/32 patients, p = 0.78). By multivariate analysis, the amount of contrast agent, but not the treatment strategy, was a predictor of the occurrence of contrast dye-associated nephrotoxicity (OR 2.58, 95% CI 1.1 to 4.9; p = 0.035). CONCLUSIONS In patients with reduced renal function undergoing angiography and/or angioplasty, the amount of contrast agent, but not the administration of prophylactic acetylcysteine, was a predictor of renal function deterioration. Prophylactic acetylcysteine might provide better protection than hydration alone, only when a small volume of contrast agent is used.
