Comparative Study of the Efficacy of Oral Versus Intravenous Hydration as a Preventive Measure of Contrast-induced Nephropathy (CIN) in Patients With Renal Insufficiency (RI) Grade III Under Study Conducting Computed Tomography (CT)

500 mL of water two hours before computed tomography and 2000 milliliters 24 hours after performing computed tomography

Intravenous hydration: sodium (1.6 molar) Bicarbonate 3 mL / kg / h starting one hour before the computed tomography and sodium bicarbonate (1/6 M) 1 mL / kg / h during the hour after computed tomography.

If there is contraindication for administration of bicarbonate the pattern of intravenous hydration is performed with saline solution: 3 ml / kg / h for 1 hour before the procedure and normal saline 1 mL / kg / hour for hour after computed tomography.