Is carbon dioxide a safe and good alternative for diatrizoate meglumine as a contrast in digital subtraction angiography?

Contrast-induced nephropathy is well-known sequelae of iodinated contrast (diatrizoate meglumine). Carbon dioxide (CO2) can be used as an alternative contrast agent. The aim of this study was to compare the renal injury and the quality of images of aortogram using iodinated contrast versus CO2 using digital subtraction angiography (DSA). This prospective randomized study was done in 29 healthy dogs using DSA aortogram. Dogs were randomly assigned to receive iodinated contrast or CO2. 6-F pigtail catheter was introduced via femoral artery approach to perform aortogram under general anesthesia. Serum creatinine (S.Cr.) and urinary enzymes, namely: N-acetyl D-glucosaminidase (NAG), alanine aminopeptidase (AAP), and gamma glutamyl transferase (GGT), were measured before and 48 hours after aortogram. There was no change in S.Cr. in both the groups. Significantly more enzymuria was seen following iodinated contrast than CO2. Enzymuria pre and postaortogram following the iodinated contrast was GGT: 14.9 ± 5.92 vs. 26.2 ± 15.1 (P = 0.001), NAG: 1.63 ± 0.90 vs. 3.6 ± 2.14 (P = 0.0001), and AAP: 1.51 ± 0.75 vs. 3.38 2.41 (P = 0.001), and in the CO2 group was GGT: 15.5 ± 4.9 vs. 21.1 ± 9.04 (P = 0.02), NAG: 2.12 ± 1.06 vs. 3.82 3.27 (P = 0.08), and AAP: 1.28 ± 0.76 vs. 2.51 ± 1.72 (P = 0.03). More than 50% increase over the preprocedural value was significantly less following CO2. Images obtained with iodinated contrast were superior to those with CO2, however, the quality of image with CO2 was adequate for delineation of the renal artery and major branches. Both iodinated contrast and CO2 cause significant enzymuria. More severe enzymuria (>50% increase) was seen significantly less with the use of CO2. Quality of images is better with iodinated contrast