Total parenteral nutrition essential fatty acid deficiency

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. 

Severe negative nitrogen balance may occasionally have to be corrected by hyperalimentation or total parenteral nutrition (TPN). Intravenous solutions used in TPN contain essential and nonessential amino acids, plus a source of calories in the form of fat and carbohydrate. They "spare" the administered amino acids and allow them to be used for tissue repair. The TPN fluid must also contain all other nutritional factors required for life, including essential fatty acids, vitamins, and minerals. Severe metal and essential fatty acid deficiencies have been observed in situations in which such inclusions had not been made. 

Richardson, T. and Sgoutas, D. (1975). Essential fatty acid deficiency in four adult patients during total parenteral nutrition. Ani. J. Ciin. Nutr. 28,258-263. 

Goodgame, J.T., Lowry, S.F., and Brennan, M.F, Essential fatty acid deficiency in total parenteral nutrition time course of development and suggestions for therapy. Surgery, 84, 271-277, 1978. 

Dietary deficiencies of essential fatty acids are rare. However, some cases have been reported in patients receiving total parenteral nutrition (TPN). Although the most obvious symptom is a red scaly dermatitis, deficiencies of essential fatty acids also result in a decreased availability of precursors for eicosanoid synthesis. 

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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