Toxic hydroperoxides in intravenous lipid emulsions used in preterm infants

The unsaturated fatty acids that make up a large component of the lipid emulsion Intralipid are highly susceptible to peroxidation, and the products of this reaction could explain the toxicity that has been associated with the administration of some emulsions. Lipid peroxidation produces hydroperoxides, which can alter arachidonic acid metabolism or react to form organic free radicals, which then stimulate a cascade of damage to endogenous lipids. The lipid hydroperoxides and their breakdown products are also mutagens and carcinogens. To determine the degree of lipid peroxidation in Intralipid, we measured the lipid hydroperoxide content of three lots of 20% Intralipid using high-performance liquid chromatography with chemiluminescence detection. The average concentration was 290 +/- 29 mumol/L (SEM) lipid hydroperoxides (n = 15), a large portion of which was made up of trilinoleate derivatives. Measurements made on Intralipid samples collected from the end of the intravenous tubing after a 20-hour infusion cycle were not significantly different from measurements made on newly opened bottles. The lipid hydroperoxide content of some lipid emulsions may represent a clinically significant risk to premature infants, particularly those with preexisting lung disease.