Comparison of short-term infusion regimens of N-acetylcysteine plus intravenous fluids, sodium bicarbonate plus intravenous fluids, and intravenous fluids alone for prevention of contrast-induced nephropathy in the emergency department.

BACKGROUND: There is no evidence regarding the several short-term prophylaxis protocols for contrast-induced nephropathy (CIN) that may be most feasibly convenient in emergency settings.

OBJECTIVES: The purpose of this study was to compare the efficacies of short-term CIN prophylaxis protocols of normal saline, N-acetylcysteine (NAC) plus saline, and sodium bicarbonate plus saline in emergency department (ED) patients at moderate or high risk of CIN after receiving intravenous (IV) contrast agent.

METHODS: This single-center, randomized, nonblinded clinical trial was conducted in the ED with adult patients requiring contrast-enhanced computed tomography (CT). Patients with moderate to high risk of CIN according to the Mehran risk score, who consented to participate, were eligible. Patients with continuous renal replacement therapy or who reported contrast allergy were excluded. Enrolled patients were randomly assigned to receive 150 mg/kg NAC in 1000 mL of 0.9% sodium chloride (NaCl), 150 mEq of sodium bicarbonate in 1000 mL of 0.9% NaCl, or 1000 mL of IV saline infusion, all given at 350 mL/hr for 3 hours. All of the patients were administered less than 100 mL of nonionic, low-osmolality contrast agent. The primary outcome of CIN was defined as a 25% increase or a greater than 0.5 mg/dL increase in the serum creatinine level 48 to 72 hours later compared with the baseline measurement.

RESULTS: A total of 107 patients were randomized to NAC (n = 36), sodium bicarbonate (n = 36), and saline prophylaxis (n = 35). The mean age of the patients was 71 years (95% confidence interval [CI] = 65 to 77 years), and 58 (54.2%) were male. The groups were similar regarding baseline characteristics and nephropathy risks. Of the 16 (14.9%) patients who eventually developed CIN, seven (19.4%) were in the NAC plus saline group, four (11.1%) were in the sodium bicarbonate plus saline group, and five (14.2%) were in the saline group. There were no significant differences between the groups in terms of the prevention of CIN (p = 0.60).

CONCLUSIONS: None of the short-term protocols with normal saline, NAC, or sodium bicarbonate was superior in ED patients requiring contrast-enhanced CT who had a moderate or high risk of CIN.