The effecfs of contrast media on the rheological properties of blood

Abstract

Contrast media can be expected to have effects on the rheology of blood because of their elevated densities, osmolarities and viscosities compared with plasma. These properties also vary markedly between the different types of media currently available and so their haemorheological effects can be expected to vary. In this in vitro study the ionic media Urografin, Cardioconray and Hexabrix have been compared with the non-ionics Optiray and Omnipaque.

All of the media caused progressive reduction in low (0.277s⁻¹) shear rate blood viscosity as their concentrations increased, reflecting the marked reduction in rouleaux formation that was induced. Simultaneously, the high (128.5 s⁻¹) shear rate viscosity increased. This is, at least in part, a reflection of the high viscosities of the media and the cellular crenation and rigidity induced by osmotic shrinkage. Of the media tested Urografin and Cardioconray had the greatest effects and Hexabrix the least.