Influence of parenteral fat emulsion Intralipos and citric acid on blood viscosity and erythrocyte morphology in vitro.

In most studies fat emulsion had been administered by enteral route. Recently a parenteral soybean-oil emulsion has been developed. In this study we assessed the effects of a parenteral soybean-oil emulsion (Intralipos) and citric acid on blood rheology and erythrocyte morphology in vitro. Porcine blood was incubated in vitro with increasing concentrations of fat emulsion Intralipos and citric acid at 37 degrees C for 1h. Viscosity of plasma and whole blood was measured using a FASCO-2050 digital viscometer. Red blood cell morphology was examined by light microscopy. The viscosity of whole blood represented an ascending dose-dependence for different Intralipos concentrations at high shear rate of 90 and 225 s(-1), however, it decreased with citric acid concentrations. On the other hand, the whole blood viscosity also declined with citric acid concentrations in presence of 30% Intralipos (v/v), and there is a minimal viscosity at 0.67% citric acid (v/v). There are some thorns on the blood membrane at 40% Intralipos as compared with control (no Intralipos addition), which indicates the Intralipos compound may affect blood cell membranes, and resulted in whole blood viscosity increase. We concluded that the intravenous soybean-oil preparation Intralipos interacts with the erythrocyte membrane, and citric acid could alleviate the whole blood viscosity.