Role of hydration in contrast-induced nephropathy in patients who underwent primary percutaneous coronary intervention.

To investigate the role of hydration to prevent contrast-induced nephropathy (CIN) in patients with ST-segment elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PPCI), we prospectively included 408 consecutive patients who were randomly assigned to receive either hydration with isotonic saline (1 ml/kg/h since the beginning of the procedure and for 24 hours after it: NS+ group) or not (NS- group). All patients received an iso-osmolar nonionic contrast medium. The primary end point was the development of CIN: ≥25% or ≥0.5 mg/dl increase in serum creatinine within 3 days after the procedure. CIN was observed in 14% of patients: 21% in the NS- group and 11% in the NS+ group (p=0.016). CIN was significantly associated with death (15.2% vs 2.8%; p<0.0001) and need for dialysis (13.4% vs 0%; p<0.0001). In multivariate analysis, the only predictors of CIN were hydration (OR=0.29 [0.14 to 0.66]; p=0.003) and the hemoglobin before the procedure (OR=0.69 [0.59 to 0.88]; p<0.0001). In conclusion, intravenous saline hydration during PPCI reduced the risk of CIN to 48%. Patients with CIN had increased mortality and need for dialysis. Given the higher incidence of CIN in emergent procedures, and its morbidity and mortality, preventive hydration should be mandatory in them unless contraindicated.