Saturated fats can be sub-classified into short chain, medium chain, and long chain fats whereas mono- and polyunsaturated fats are all long chain fats. In contrast, if the first double bond that occurs in the sixth carbon atom it is called ω-6 FA, and the FA is called ω-3, if the double bond occurs in the third carbon atom. The fatty acid that has its first double bond occurring in the ninth carbon atom, for example, is called ω-9 FA. The location of the first double bond, counting from the methyl end of the molecule, is called the ω carbon. Saturated FAs have no double bonds, monounsaturated FAs (MUFAs) have one double bond, and polyunsaturated FAs (PUFAs) have two or more double bonds. Short chain FAs (SCFAs) have 2–4 carbons, medium chain FAs (MCFAs) have 6–12 carbons, while long chain FAs (LCFAs) have more than or equal to 14 carbons. A soybean oil lipid emulsion (SOY) has been the mainstay of parenteral nutrition lipid formulations since its adoption in Europe with approval in 1961 and subsequently in the United States a decade later.įAs are an important component of IVLE, and are classified based on several characteristics including the carbon chain length, degree of unsaturation, and location of the first double bond. Although history would expound experimentation with fat administration as early as the 17th century, a safe and viable lipid emulsion was only developed for routine administration in the early 1960s. IVLEs are suspensions of oil in an aqueous medium manufactured to possess properties to naturally occurring chylomicrons, and are unstable systems that are subject to physical changes over time. TGs constitute molecules of glycerol to which three fatty acids (FAs) have been esterified. Lipids consist of triglycerides (TGs), sterols and phospholipids. Furthermore, lipids serve as substrate for de novo biosynthesis of cholesterol and endogenous steroids and as precursors of modulators of inflammation and platelet function (leukotrienes, thromoboxanes). Fatty acids form the major constituent of cellular bio-membranes and contribute to membrane integrity, regulate permeability and are precursors to key modulators involved in cellular pathways of the immune system. In addition, lipids have multiple physiological roles in the body that are biologically vital. Intravenous lipid emulsions (IVLEs) are a source of essential fatty acids (EFAs) and energy-dense non-protein calories. Background of Intravenous Lipid Emulsions (IVLEs) The objective of this article is to review the history of IVLE, their composition, the different generations of widely available IVLE, the variables to consider when selecting lipids, and the complications of IVLE and how to minimize them.ġ. Emerging literature has indicated that there are benefits to utilizing alternative lipids such as olive/soy-based formulations, and combination lipids such as soy/MCT/olive/fish oil, compared with soybean based lipids, as they have less inflammatory properties, are immune modulating, have higher antioxidant content, decrease risk of cholestasis, and improve clinical outcomes in certain subgroups of patients. Utilizing intravenous lipid emulsions in parenteral nutrition has minimized the dependence on dextrose as a major source of nonprotein calories and prevents the clinical consequences of essential fatty acid deficiency. Soybean oil lipid emulsions have been the mainstay of parenteral nutrition lipid formulations for decades in North America. Lipids have multiple physiological roles that are biologically vital.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |