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 °C for 1 h. 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.