FAT EMULSIONS FOR PARENTERAL-NUTRITION .3. LIPOFUNDIN MCT/LCT REGIMENS FOR TOTAL PARENTERAL-NUTRITION (TPN) WITH LOW ELECTROLYTE LOAD

The physical stability of three regimens for total parenteral nutrition (TPN) based on the MCT/LCT (50:50) emulsion Lipofundin MCT/LCT(1) was investigated. A range of different methods was employed for complete characterization of the feeding mixtures (sizing methods: photon correlation spectroscopy, microscopic photography, Coulter counter, laser diffractometer; zeta potential determination: laser Doppler anemometry). The regimens contained about 70 mmol/l 1:1 electrolytes and increasing concentrations of divalent cations (1.0-4.7 mmol/l, e.g., calcium, magnesium). During the storage period of 21 days the mean diameter and the width of the bulk population remained unchanged. No increase in the number of particles larger than the bulk population could be detected in the homogeneous mixtures of the regimens (after shaking). Analysis of the top phase (surface layer) revealed a sight increase in the number of large particles in the two regimens with higher content of divalent cations. This indicates the importance of the sampling procedure. Microscopic and Coulter counter analysis proved to be most sensitive in detecting these larger droplets. All three regimens were considered as physically stable for at least 21 days.