Patients who undergo radiographic procedures are at risk for contrast induced nephropathy due to the nature of the contrast agent used. CIN is also associated with renal failure, hemodialysis, mortality, morbidity, and cost. Methods to prevent CIN include mucomyst, which has shown mixed results, but the most common method is hydration with normal saline. A smaller and more recent study (n=119) has shown sodium bicarbonate solution to be more beneficial. Is sodium bicarbonate truly better at preventing contrast induced nephropathy compared to normal saline? The general hypothesis is that sodium bicarbonate is more effective at preventing CIN than normal saline. Inclusion criteria: GFR <60 mL/min/1.73m^2, older than 18, and at least one secondary risk factor. Secondary risk factors include type II diabetes, hypertension, older than 75, or history of congestive heart failure (CHF). Exclusion criteria: inability to give consent, already receiving sodium bicarbonate, undergoing emergency cardiac catherization, receiving contrast agent other than Oxilan, on hemodialysis, exposure to contrast within the past 48 hours, pulmonary edema, active CHF, severe valvular abnormality, significant change in kidney function in the past 48 hours (change in GFR > 15%), heart transplant, one kidney, or kidney transplant status. Patients are randomized to either normal saline or sodium bicarbonate. CIN is defined as a decrease in GFR greater than 25% within the first four days following catherization. Interim analyses show no difference among the efficacy of the two fluids.