肠内营养中应该考虑的几个问题青岛纽的.ppt

安素粉剂可作为唯一营养来源或部分营养补充，适用于成人及四岁或四岁以上儿童，可口服或管饲。 The lining of the small intestine is called the mucosa. The mucosa contains finger-like projections called the villi; hair-like projections on the villi are called the microvilli. The villi and microvilli perform all nutrient absorptive functions of the small bowel. Additionally, they keep the normal bacteria that live in the GI tract from entering the blood stream. The villi and microvilli are dependent upon nutrients going through the GI tract to maintain their health. After about 3 days without nutrition, the microvilli begin to atrophy and malabsorption can occur. Over the long-term, this becomes a serious issue as the absorptive and barrier functions decline with time and the entire GI tract becomes compromised. Since elemental formulas can be readily absorbed and thus well tolerated by patients with GI impairment, they allow nutritional support through the GI tract for patients who would otherwise require TPN. Free amino acids and short-chain peptides can be absorbed directly. Thus, the protein source of elemental formulas does not require digestion. The low fat content of elemental formulas means less work for the pancreas in producing enzymes to aid in fat digestion. Low fat formulas should also leave the stomach more quickly and help to decrease residuals. Peptinex? DT provides a combination of free amino acids and primarily short-chain peptides. Peptinex DT is the first formula designed to optimize the use of the Dual Transport System. Examples of 100% free amino acid formulas are: Vivonex? RTF, Vivonex? Plus, Vivonex? T.E.N., Vivonex? Pediatric, Tolerex? and f.a.a.?. Mildly hydrolyzed and intact proteins require multiple steps in digestion of the long-chain peptides to amino acids and short-chain peptides prior to absorption. Moderate to high levels of fat must be broken down by digestive enzymes. Examples of intact protein formulas include: Isosource?, Fibersource?, Compleat?, Isocal? and Os