Fatty acids, essential with parenteral nutrition

A fish oil-based intravenous lipid emulsion in the treatment of liver disease associated with parenteral nutrition has been compared with soybean oil in an open study in 42 infants with short bowel syndrome who developed cholestasis [35 ]. There were three deaths and one liver transplantation in those who received the fish oil, compared with 12 deaths and 6 transplants in those who received soybean oil The fish oil was not associated with hypertriglyceridemia, coagulopathy, or deficiency of essential fatty acids. 

Amino acid-glucose solutions used in total parenteral nutrition of humans lack choline. The lipid emulsions that deliver extra calories and essential fatty acids during parenteral nutrition contain choline in the form of lecithin (20% emulsion contains 13.2 mmol 1 ). Humans treated with parenteral nutrition require 1-1.7 mmol of choline-containing phospholipid per day during the first week of parenteral nutrition therapy to maintain plasma choline levels. 

Essential fatty acid deficiency is rare but can occur with prolonged lipid-free parenteral nutrition, very low fat enteral formulas, severe fat malabsorption, or severe malnutrition. The body can synthesize all fatty acids except for linoleic and linolenic acid, which should constitute approximately 2% to 4% of total calorie intake. 

Linoleic acid and alpha-linoleic acid are essential fatty acids that are provided in any long-term parenteral nutrition by administering fat emulsions at least twice a week. Fatty acid deficiency is a common complication of severe end-stage liver disease. The ability of short-term intravenous lipid supplementation to reverse fatty acid deficiencies has been studied in patients with chronic liver disease and low plasma concentrations of fatty acids (914). Shortterm supplementation failed to normalize triglycerides. 

FAT EMULSION For parenteral nutrition a fat emulsion for intravenous administration is used. Preparations contain a fractionated soya-oil emulsified with some fractionated egg phospholipids. About 60% of the fatty acids are essential fatty acids the particle size and biological properties are similar to those in natural chylomicrones. 

A similar need for these fatty acids in human diets has been established more recently. Deficiency symptoms can be demonstrated in children (S6 derhjelm et al, 1970) and have also been seen in adults after prolonged parenteral nutrition with fat-deficient preparations (Collins et al, 1971 Riella et al, 1975). It is estimated that these various deficiency symptoms can be prevented by an intake of essential fatty acids in the range of 1 to 2% of total calories (Holman, 1970). 

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