Studies of iodixanol in the rabbit lung and peritoneum

To evaluate a new water-soluble contrast agent, iodixanol. The study evaluates absorption from the peritoneal cavity and toxicity in the lung.

Thirty New Zealand white rabbits were given the study agent and comparative agents into an endotracheal tube. Serial chest radiographs were evaluated for development of pulmonary edema. All lungs were evaluated histopathologically for toxic inflammatory response. Fifteen different rabbits were given intraperitoneal injection of the study and comparative contrast agents. Serial abdomen radiographs, taken up to 24 h after injection, were evaluated for contrast absorption from the peritoneal cavity.

Evaluation of indicators of pulmonary edema demonstrated that iodixanol caused the same or less pulmonary edema than comparative agents. Histopathologic analysis showed that iodixanol caused less macrophage response than saline (P = 0.010), the same lymphocyte infiltration as saline (P = 0.472), the same neutrophil response as saline (P = 0.297), and the same vasculitic reaction as saline (P = 0.128). Compared to iohexol 270, iodixanol caused the same macrophage infiltrate (P = 0.924), the same lymphocyte infiltration (P = 0.523), more neutrophil reaction (P = 0.007), and less vasculitic reaction (P = 0.042). Iodixanol was rapidly absorbed from the peritoneal cavity.

Iodixanol is a new contrast agent that is isotonic at all clinically useful iodine concentrations. It appears safe in the lung and is absorbed from the peritoneal cavity.