Enteral nutrition metabolic

T. R. Ziegler, K. Benfele, R. J. Smith, et al. Safety and metabolic effects of 1-giutamine administration in humans. Journal of Parenteral and Enteral Nutrition 14, 1375 (1990). 

Impaired absorption of all or selected nutrients, diarrhea Nausea and vomiting, inability to ingest nutrients orally or by enteral nutrition Increased energy expenditure and protein requirements, altered metabolism, anorexia, malabsorption Anorexia, food aversion... 

The gastrointestinal (Gl) tract defends the host from toxins and antigens by both immunologic and nonimmunologic mechanisms, collectively referred to as the gut barrier function. Whenever possible, enteral nutrition (EN) is preferred over parenteral nutrition (PN) because it is as effective, may reduce metabolic and infectious complications, and is less expensive. 

Nutrition is utilized to provide general support for the debilitated patient with a chronic illness. Often, patients are deficient in protein, calories, potassium, vitamins, etc. The healing process is impaired by poor nutrition and is enhanced by proper nutrition. In some cases enteral nutrition is not practical or is impossible. With the techniques of total parenteral nutrition, it is now possible to provide nutritional support for almost all types of patients. Specific nutritional therapy is necessary in certain types of metabolic and related diseases. Nutritional therapy is essential in conditions where specific food intolerances are the basis for a disease. 

Maintaining adequate nutritional status, especially during periods of illness and metabolic stress, is an important part of patient care. Malnutrition in hospitalized patients is associated with significant complications, including increased infection risk, poor wound healing, prolonged hospital stay, and increased mortality, especially in surgical and critically ill patients.1 Specialized nutrition support refers to the administration of nutrients via the oral, enteral, or parenteral route for therapeutic purposes.1 Parenteral nutrition (PN), also... 

Chiolero R, Schneiter P, Cayeux C, Temler E, Jequier E, Schindler C, Tappy L. Metabolic and respiratory effects of sodium lactate during short i.v. nutrition in critically ill patients J Parenter Enteral Nutr 1996 20(4) 257-63. 

Once a chemical enters the body of animal or human, it undergoes metabolic reaction. A host of factors modulate the reaction rate and the induction of toxicological effects. These factors have been termed intrinsic factors and include animal species, gender, age, nutritional status, pregnancy, other health status, and circadian rhythms. In addition, there are certain extrinsic factors (e.g., physicochemical properties of chemicals, solvent or vehicle, route of exposure, temperature, and humidity) during exposure to chemicals that also influence the effect of a test chemical. We shall discuss these factors in greater detail. 

Otable isotopes are new tools for nutritionists that enable researchers to label nutrients for human experiments without exposing study participants to radioactivity. In addition some elements have no suitable radioisotopes, and stable isotopes provide the only means of conducting experiments with labels. This field of research relies heavily on expertise in sophisticated chemical techniques and analytical instrumentation, and nutritionists have entered the field only recently. The field is in its infancy, but is now expanding rapidly there is widespread interest in use of stable isotopes to study nutrient bioavailability, metabolism, and utilization. Many approaches and analytical methods are being developed for use of stable isotopes in nutrition research. 

Kinney, J. M. (1987). kidiiect calorimetiy in malnutrition Nutritional assessment or thcra-preutic reference /. Parenteral Enteral Nutr. 11, 90S-94S-Pellet, P L. (1990). Food eneigy requirements in humans. Am.. Clin, Nutr. 51,711-722. Ravussin, E., Bumand, B., hutz, ., and Jaquier, E- (1962). Twenty-foulabour eneigy expenditure and resting metabolic rate in obese, moderately obese, and control subjects. Am.. Clin. Nutr. 35,36 573. 

Kushjter, R. E, (1986). Total parecueral nutrition-associated metabolic acidosis, /. Piitenteral Enteral. ttr. 10, 306-310. 

Metabolic bone disease in children receiving parenteral nutrition manifests primarily as osteopenia and, on occasion, fractures (5). The etiology is multifactorial calcium and phosphate deficiency play a major role in the preterm infant but the part played by aluminium toxicity in this population is unknown. Lack of reference values of bone histomorphometry in the premature infant, as well as lack of reference data for biochemical markers of bone turnover in these patients, contributes to the uncertainty. Other factors that may play a role in the pathogenesis of bone disease associated with parenteral nutrition include lack of periodic enteral feeding underljdng intestinal disease, including malabsorption and inflammation the presence of neoplasms and drug-induced alterations in calcium and bone metabohsm. However, the true incidence and prevalence of parenteral nutrition-associated bone abnormalities in pediatric patients are unknown. 

Velez RJ, Myers B, Guber MS. Severe acute metabolic acidosis (acute beriberi) an avoidable complication of total parenteral nutrition. J Parenter Enteral Nutr 1985 9 216-9. 

Trujillo EB, Young LS, Chertow GM, et al. Metabolic and monetary costs of avoidable parenteral nutrition use. JPEN J Parenter Enter Nutr 1999 23 109-113. 

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