This will be a prospective, randomized trial to determine if differences exist in the tolerance of lipid injectable emulsions in the neonatal intensive care unit (NICU). Lipid injectable emulsions are an essential nutrient for neonatal growth and development. Traditionally, lipid injectable emulsions have been commercially available in sterile glass bottles, but in April of 2004, a new container was introduced as a sterile plastic bag. In January, 2005, NICU personnel observed what appeared to be a higher than usual incidence of hypertriglyceridemia. Upon further laboratory investigation of the lipid injectable emulsions stored in glass bottles versus those in plastic, significant differences were noted in the population of large-diameter fat globules by globule size analysis, reflective of a less stable emulsion in plastic. The United States Pharmacopeia (USP) which sets the standards for drug purity and safety in the U.S., and whose drug monographs are enforceable by the FDA, has proposed to limit this large diameter fat globule population to a volume-weighted percent fat greater than five micrometers or PFAT5 to be less than 0.05% of the total lipid concentration. (At the present time, the USP monograph is not officially recognized, but is on track for adoption in 2006.) Our preliminary analyses of four lots of 20% lipid injectable emulsion packaged in glass to have a PFAT5 of 0.003±0.0008%, compared to an approximate 55-fold increase in the large-diameter fat globule population or 0.166±0.016% for an equal number of products packaged in plastic. We hypothesize this difference may explain the recent clinical observations. We will compare the incidence of hypertriglyceridemia in neonates between lipids packaged in glass versus those in plastic. The study will attempt to discern whether the differences in packaging influence the stability and subsequent tolerance of lipid injectable emulsions.