Effects of perfluorocarbon emulsion in rheology.

AIM To study effects of a perfluorocarbon emulsion on plasma and whole human blood viscosity in the presence of albumin or modified fluid gelatin. MATERIAL AND METHODS We investigated the effects of several PFC concentrations on plasma and whole blood viscosity in the presence of human albumin solution (HAS) or modified fluid gelatine (MFG; Gelofusine) to obtain three PFC emulsion concentrations (4, 8 and 15 g/dL). Three hematocrit levels (Hct) were investigated: 30, 20 and 13%, corresponding to different clinical situations. Plasma and whole blood viscosity was measured at 37 degrees C, using a Couette viscometer for shear rates ranging from 0.2 to128 s(-1). RESULTS AND DISCUSSION All PFC concentrations increased plasma and whole blood viscosity for the same Hct. Viscosity values similar to physiological ones were observed at Hct 13%, with MFG - PFC 4, 8 g/dL and HAS - PFC 15 g/dL; at Hct 20%, with MFG - PFC 4g/dL and HAS - PFC 15 g/dL; at Hct 30%, and HAS - PFC 4, 8 g/dL. CONCLUSIONS We conclude that this PFC emulsion increases plasma and blood viscosity and that among the three studied volume expanders, the interaction with MFG can result in viscosity values above the physiological one even at low Hct values. Our results suggest that such increased blood viscosity could decrease skeletal muscle oxygen pressure.