Renal effects of low and isoosmolar contrast media on renal hemodynamic in a normal and ischemic dog kidney.

RATIONALE AND OBJECTIVES:The authors investigated the comparative effects of a nonionic dimer contrast medium (iodixanol) with an ionic low osmolar contrast media (locm) (ioxaglate) on renal blood in a normal and an ischemic dog kidney. METHODS:Six dogs were studied for two periods. During the first period (the control period) a renal arteriography was performed with either iodixanol (Visipaque) or ioxaglate (Hexabrix) in a randomized order. Twenty minutes after applying a suprarenal clamp just above the right renal artery, two selective intrarenal contrast media administrations were performed at 30-minute intervals in a randomized order (ischemic period). RESULTS:During the control period ioxaglate and iodixanol induced no change in mean arterial blood pressure and pulse rate. The maximum decrease in renal blood flow (rbf) observed with ioxaglate was 19 +/- 4%. The maximum decrease in rbf observed with iodixanol was 51 +/- 16% versus control period (P = 0.05 compared with ioxaglate). During the ischemic period, renal perfusion pressure was 72 +/- 2 mm Hg and 73 +/- 2 mm Hg before iodixanol and ioxaglate administration, respectively (P = NS). Iodixanol induced a 61 +/- 11% decrease in RBF. These changes were significantly higher than those observed with ioxaglate during the control period and with the control ischemic period. Ioxaglate induced a maximum 11 +/- 6% decrease in RBF at 1 min (P < 0.05 versus iodixanol). These modifications were not significantly higher than those observed during the control period. CONCLUSIONS:In this study the authors found that the renal effect of iodixanol are markedly more pronounced than that of ioxaglate. In the setting of ischemia the effects of iodixanol were only slightly enhanced whereas those of ioxaglate were not modified.