The most effective regimen for the prevention of contrast-induced nephropathy (CIN) remains unknown. Therefore researchers conducted a RCT in 258 consecutive patients with renal insufficiency undergoing intravascular contrast procedures to compare two regimens of sodium bicarbonate with 24 hours of a sodium chloride 0.9% infusion in the prevention of CIN

Patients were randomised to receive IV volume supplementation with one of the following:

• sodium chloride 0.9% 1 mL/kg/h for at least 12 hours prior and after the procedure

• sodium bicarbonate (166 mEq/L) 3 mL/kg for 1 hour before and 1 mL/kg/h for 6h after the procedure

• sodium bicarbonate (166 mEq/L) 3 mL/kg over 20min before the procedure plus sodium bicarbonate orally (500 mg per 10 kg)

The primary endpoint was the change in estimated glomerular filtration rate (eGFR) within 48 hours after contrast. Secondary endpoints included the development of CIN.

The following findings were reported:

• The maximum change in eGFR was statistically significantly greater in Group B vs. Group A (mean difference −3.9 [95% CI, −6.8 to −1] mL/min/1.73 m2, p = 0.009) and similar between Groups C and B [mean difference 1.3 [−1.7 to 4.3] mL/min/1.73 m2, p = 0.39].

• The incidence of CIN was statistically significantly lower in Group A (1%) vs. Group B (9%, p = 0.02) and similar between Groups B and C (10%, p = 0.9).

The researchers conclude that volume supplementation with 24 hours sodium chloride 0.9% is superior to sodium bicarbonate for the prevention of CIN and a short-term regimen with sodium bicarbonate is non-inferior to a 7 hour regimen.