Lipid infusion with different triglyceride cores (long-chain vs medium-chain/long-chain triglycerides): effect on plasma lipids and bilirubin binding in premature infants.

The possible beneficial effects of infusing a lipid emulsion containing 50% by weight of medium-chain triglycerides (MCT) compared with a standard long-chain triglyceride (LCT) emulsion were studied in 18 premature neonates (gestational age less than 34 weeks) requiring parenteral nutrition. The infants were assigned in a double-blind manner to receive one of the two lipid emulsions over 17 hours a day as a supplemental regimen for total parenteral nutrition. A lipid load of 1 g/kg per day was initiated on the third day of life and was increased at the rate of 1 g/kg per day until a maximal dose of 3 g/kg per day was obtained on the fifth day of life and maintained thereafter. Both bound and unbound bilirubin decreased with both infusion regimens during the study period. Despite a marked increase in plasma free fatty acid levels (260% in the MCT/LCT group compared with 210% in the LCT group), the fraction of unbound (free) bilirubin was significantly lower in the MCT/LCT group (34% vs 13%). Free fatty acid levels, corrected to albumin, were positively correlated to the percentage of free bilirubin only for the LCT lipid infusion. The finding of a significant elevation of plasma cholesterol levels only in the MCT/LCT group is now under investigation. Use of the MCT-containing emulsion was not associated with a higher frequency of adverse effects than the commonly used LCT-containing emulsion.(ABSTRACT TRUNCATED AT 250 WORDS)