The effect of dyes used to evaluate the in situ, ex-vivo, and perfused kidney.

Methylene blue, indigo carmine, and fluorescein dyes were evaluated to determine their effect on the dog kidney. Methylene blue and indigo carmine were administered intravenously and intraarterially to the in situ vascularized kidney and serial histologic appearance of the kidney was determined. The three dyes were administered intraarterially to excised kidneys that were then preserved for 1 hour in the cold and autotransplanted; and finally the three dyes were administered to the perfusate of excised kidneys that were perfused for 18 hours by cryoperfusion with an albumin perfusate and then autotransplanted. Renal function and histology were determined 5 days after autotransplantation. Methylene blue dye did not damage the in situ vascularized kidney as judged by renal histology. However, administration of methylene blue to the ex vivo kidney that was subsequently short term cold stored or perfusion stored was associated with marked apparent ischemic damage of the organ. Indigo carmine dye did not adversely affect either the in situ vascularized kidney or the short term cold stored kidney. However, with perfusion storage, indigo carmine produced apparent vasoconstriction that led to perfusion failure. Fluorescein dye was not harmful to the kidney either during short term cold storage or during perfusion preservation. It is concluded that fluorescein is the dye of choice for evaluating the vascular anatomy or macroperfusion status of the kidney.