Central and renal haemodynamic effects of intravenous infusion of non-ionic and ionic contrast media. An experimental investigation in the pig.

The central and renal haemodynamic effects after intravenous infusion (1 ml/s) of a non-ionic (iohexol) and an ionic (metrizoate) contrast medium were investigated in 16 pigs. The injected contrast media induced marked haemodynamic changes compared with normal saline. However, there were no significant differences between the ionic and the non-ionic media. It was concluded that the effects were only partially caused by an increase in the blood volume due to the injected volume. In addition, the effects related to the viscosity, the osmolality and other not specified pharmacodynamic properties of the media are proposed to be of importance.