Effect of hydration with or without n-acetylcysteine on contrast induced nephropathy in patients undergoing coronary angiography and percutaneous coronary intervention

Contrast induced nephropathy (CIN), an acute decline in renal function after the administration of intravenous contrast in the absence of other causes, is the third leading cause of acute renal failure in hospitalized patients. Antioxidant N-acetylcysteine prevents acute contrast nephrotoxicity in patients with impaired renal function who underwent coronary angiography (CAG) and percutaneous coronary intervention (PCI). Hydration is the cornerstone in preventing CIN. N-acetylcysteine has additive preventive affect. We compared N-acetylcysteine plus hydration with hydration alone in preventing CIN. Patients were assigned to receive either premedication with hydration with normal saline (1ml/kg/hour-12 hour before and 12 hour after CAG and intravenous PCI) alone or to receive both hydration and oral N acetylcysteine (600mg bid for 2 days, starting day before CAG and PCI). Main out come was occurrence of ≥25% or ≥0.5mg/dl increase in serum creatinine level within 24 to 48 hours after contrast administration; change in creatinine clearance and serum creatinine level. Six patients (12%) of hydration group i.e. Group A and none of the patients of N-acetylcysteine All group i.e. Group B develop CIN (p=0.012). Baseline serum creatinine level was slightly higher in N-acetylcysteine group than hydration group (1.52±0.32 and 1.44±0.22). After 24 hours of CAG and PCI serum creatinine level lower than base line in N-acetylcysteine group but slightly higher than base line in hydration group (1.42±0.39 and 1.51±0.38). Difference in serum creatinine in both the groups were statistically significant (p=0.006 in N-acetylcysteine group and p=0.029 in hydration group). Creatinine clearance rate significantly improved in N-acetylcysteine group after coronary intervention. In conclusion, N-acetylcysteine and hydration prevent CIN better than hydration alone in high risk patients.