Pulmonary edema induced by intravenous administration of contrast media: experimental study in rats.

An experimental study of changes in the lung induced by the intravenous administration of iodinated contrast media was carried out using rats. The increase in the relative lung weight and histological findings, especially pulmonary edema, were evaluated in control, physiological saline, diatrizoate sodium meglumine, iohexol, and ioxaglate groups. The relative lung weight increased significantly in all contrast media groups. Proximal and distal perivascular edema were confirmed microscopically. No statistically significant differences among the contrast media were noted in the increase in relative lung weight or in the degree of perivascular edema. There was a close correlation between the increase in relative lung weight and the degree of perivascular edema. These physiological and histological changes in the lung occurred irrespective of the osmolality of the contrast materials. We considered these phenomena to be induced by non-osmolality related toxicity of the contrast medium.