Previous studies have suggested that olive oil-based emulsion is safe and well tolerated in preterm infants, a showed efficacy and a good clinical and biological safety profile. The objective of this study was to assess the effects of a new olive-oil based lipid emulsion compared with the traditional lipid emulsions.

For a number of years, lipid emulsions have been used in the nutritional support of surgical and critically ill patients, with the aim of supplying substrates to meet energy demands and providing building blocks for wound healing and tissue repair. Two types of lipid emulsions are currently used for adult as well as pediatric patients: one lipid emulsions prepared from soybean oil that are composed of long-chain triacylglycerols (LCTs), 62% of which are polyunsaturated fatty acids (PUFAs), and the other lipid emulsions composed of 50% medium-chain triacylglycerols (MCTs) and 50% LCT soybean oil. A new lipid emulsion prepared from a mixture of soybean oil and olive oil contains only LCTs and has a lower proportion (20%) of PUFAs and 60% monounsaturated fatty acids (MUFAs). There are so many investigations with olive oil-based emulsion including in-vitro studies, animal studies, and infusion studies in healthy subjects and in various patient groups. In-vitro and animal studies demonstrate that the impairment of immune function, especially of T cell responses, that occurs with soybean oil-based emulsions is avoided with ClinOleic. Studies in infants and adults have consistently shown that olive oil-based emulsion increases the oleic acid content of blood lipids and that it avoids the depletion of long chain n-6 PUFA derivatives of linoleic acid that is seen with soybean oil-based emulsion. The less unsaturated nature of olive oil-based emulsion compared will possibly decrease oxidative stress. Further studies are required to test their beneficial effect from olive oil consumption in preterm infants.

The investigators designed a double-blind, randomized clinical trial to performed the effect of lipometabolism, oxidative stress and clinical outcomes of olive oil , MCY/LCT and LCT lipid emulsions.

Inclusion Criteria:

• Infants of both genders
• Hospitalized
• The parent of the infant agreed to participate by signing an informed consent form
• Infants admitted hospital within 72 hours after birth(gestational age<37 weeks)
• Birth weight <= 2000g
• No PN support contraindications
• Parenteral nutrition for 14 days or more
• The parent of the infant is to sign an informed consent form prior to enrollment

Exclusion Criteria:

• Receiving PN before screening
• EN caloric>10%
• Obstruction jaundice
• Suspected or identified biliary tract atresia
• Neonatal hepatitis
• Infants with liver markers >2 times normal levels
• Infants with renal markers >2 times normal levels
• Congenital metabolic situations
• Identified as having major chromosomal disease
• CMV, virus hepatitis and syphilis infection
• Congenital or acquired immune deficiency