Sodium bicarbonate vs sodium chloride for the prevention of contrast medium-induced nephropathy in patients undergoing coronary angiography: a randomized trial.
CONTEXT
Sodium bicarbonate has been suggested as a possible strategy for prevention of contrast medium-induced nephropathy, a common cause of renal failure associated with prolonged hospitalization, increased health care costs, and substantial morbidity and mortality.


OBJECTIVE
To determine if sodium bicarbonate is superior to sodium chloride for preventing contrast medium-induced nephropathy in patients with moderate to severe chronic kidney dysfunction who are undergoing coronary angiography.


DESIGN, SETTING, AND PATIENTS
Randomized, controlled, single-blind study conducted between January 2, 2006, and January 31, 2007, and enrolling 353 patients with stable renal disease who were undergoing coronary angiography at a single US center. Included patients were 18 years or older and had an estimated glomerular filtration rate of 60 mL/min per 1.73 m(2) or less and 1 or more of diabetes mellitus, history of congestive heart failure, hypertension, or age older than 75 years.


INTERVENTIONS
Patients were randomized to receive either sodium chloride (n = 178) or sodium bicarbonate (n = 175) administered at the same rate (3 mL/kg for 1 hour before coronary angiography, decreased to 1.5 mL/kg per hour during the procedure and for 4 hours after the completion of the procedure).


MAIN OUTCOME MEASURE
The primary end point was a 25% or greater decrease in the estimated glomerular filtration rate on days 1 through 4 after contrast exposure.


RESULTS
Median patient age was 71 (interquartile range, 65-76) years, and 45% had diabetes mellitus. The groups were well matched for baseline characteristics. The primary end point was met in 13.3% of the sodium bicarbonate group and 14.6% of the sodium chloride group (relative risk, 0.94; 95% confidence interval, 0.55-1.60; P = .82). In patients randomized to receive sodium bicarbonate vs sodium chloride, the rates of death, dialysis, myocardial infarction, and cerebrovascular events did not differ significantly at 30 days (1.7% vs 1.7%, 0.6% vs 1.1%, 0.6% vs 0%, and 0% vs 2.2%, respectively) or at 30 days to 6 months (0.6% vs 2.3%, 0.6% vs 1.1%, 0.6% vs 2.3%, and 0.6% vs 1.7%, respectively) (P > .10 for all).


CONCLUSION
The results of this study do not suggest that hydration with sodium bicarbonate is superior to hydration with sodium chloride for the prevention of contrast medium-induced nephropathy in patients with moderate to severe chronic kidney disease who are undergoing coronary angiography.


TRIAL REGISTRATION
clinicaltrials.gov Identifier: NCT00312117.