Parenteral feeds

Heyland DK, Dhaliwal R, Drover JW, et al. Canadian clinical practice guidelines for nutrition support in mechanically ventilated, critically ill adult patients. J Parenter Enteral Nutr 2003 27 355-373. Kudsk KA, Croce MA, Fabian TC, et al. Enteral versus parenteral feeding Effects on septic morbidity after blunt and penetrating abdominal trauma. Ann Surg 1992 215 503-513. 

To define the incidence of fractures and rickets that we were encountering in infants who required prolonged parenteral feeding, we reviewed the roentgenograms of a series of preterm infants who developed necrotizing enterocolitis and who required at least four weeks of total parenteral nutritional support (4). These data are recorded in Table I. 

Peptides are now included in some parenteral feeds for patients because they have less effect than amino acids on the osmotic pressure of the solution. Osmotic pressure can be a problem since the feed enters the blood directly. 

This latter situation is particularly beneficial for patients who are being fed intravenously because, if triacylglycerols containing medium-chain fatty acids are included in parenteral feeds, they are readily converted into ketone bodies so that a soluble fat fuel is rapidly made available in the blood that can be oxidised by most tissues. 

There is considerable discussion in the medical literature on the relative merits of enteral or parenteral feeding. For enteral feeding, the choice is between elemental (or monomeric) preparations, which contain glucose and amino acids, or polymeric preparations which contain protein and... 

Table 18.4 Composition of two parenteral feeds designed to stimulate the immune response...

Arginine Arginine is a precursor for a number of compounds, including proline and nitric oxide. Nitric oxide is a signalling molecule, proline is needed for formation of collagen, some of which is needed for provision of new tissue. Arginine has been shown to be benehcial for the healing of wounds and for this reason is included in some parenteral feeds (Table 18.4). 

Neuzil, J., Darlow, B. A., Inder, T. E., Sluis, . B., Winterboum, . C., and Stocker, R. (1995), Oxidation of parenteral lipid emulsion by ambient and phototherapy lights Potential toxicity of routine parenteral feeding, J. Pediatr., 126, 785-790. 

Enzymatic hydrolysis of food proteins yields peptides that are of great interest to the food industry and are utilized for various purposes, e.g., improving the functional properties of foods, parenteral feeding (casein hydrolyzates), or milk protein substitutes in cases of intolerance. 

As with adults, aluminum intake from aluminum-containing medication, such as antacids, buffered aspirins, and antidiarrheal agents would overwhelm ordinary dietary intakes (Pennington and Schoen 1995). Children may also be exposed to aluminum from vaccinations, parenteral feeding of premature infants, dialysis fluids, and treatment for hyperphosphatemia. 

All amino acids, peptides, and proteins can participate in the Maillard reaction. Reactivity of essential and nonessential amino acids is of importance in relation to, for example, intravenous (parenteral) feeding, but, in general, by far the greatest attention is paid to lysine, because it is not only an essential amino acid, which may be limiting in the diet, but also because its e-amino group remains reactive, even in peptides and proteins. 

For short-term feeding (less than 14 days) NICE (2006) recommends parenteral feeding via a peripheral venous catheter for those patients who do not need central access. A GTN patch can be applied above the peripheral venous catheter site to promote vasodilatation of the vein for those patients who have narrow veins. Some TPN is unsuitable for peripheral administration due to the nitrogen and glucose concentration these must go through a central venous catheter. 

Washington, C. Davis, S.S. The production of parenteral feeding emulsions by microfluidizer. Int. J. Pharm. 1988,... 

Changes in gait and reflexes indicates malfunctions of the cerebellum (Sturman et al, 1985). (The cerebellum is the part of the brain used to control the coordination of movements of the extremities.) Apparently, taurine serves some unique functions in the nervous system. These findings have prompted food companies to include taurine in their infant formulas and in solutions intended for parenteral feeding. However, whether humans can benefit from taurine in the diet is not clear. 

Kudsk KA, Croce MA, Eabian TC, et al. Enteral versus parenteral feeding Effects on septic morbidity after blunt and penetrating abdominal trauma. Ann Surg 1992 215 503-513. 

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