Enteral feeding formula

Enteral feeding formulas can be categorized based on caloric density. Standard caloric density is 1 to 1.3 kcal/mL. More calorically dense formulas containing 1.5 to 2 kcal/mL are also available and have a higher osmolality. When choosing an EN formula, the patient s fluid status should dictate the caloric density selected. Fluid-overloaded patients may benefit from more calorically dense formulas. It should be recognized that... 

The newer generation of enteral feeding formulas marketed for use in these populations covers a broad spectrum of characteristics (Table 98-5). Whereas some are polymeric, others are oligomeric to address the malabsorption that sometimes accompanies high stress. Some of the formulas marketed for use in critical illness are calorically dense (1.5-2 kcal/mL) to... 

TABLE 98-5. Enteral Feeding Formulas Marketed for Use in High Stress, Pulmonary Disease, and Trauma... 

Enteral feeding formulas Phenytoin Reduced effect of phenytoin Reduced absorption of Phenytoin... 

Occluded feeding tube lumen Insoluble complexation of enteral formula and medication(s) Inadequate flushing of feeding tube Undissolved feeding formula... 

Mixing liquid medications with certain enteral feeding formulations has been associated with several types of physical incompatibilities including granulation, gel formation, separation, and precipitation. Not only can these physical incompatibilities inhibit drug absorption, gel formation potentially may clog small-bore enteral feeding tubes. Physical incompatibility with medications is more common in formulations that contain intact protein than in those with hydrolyzed protein. Also, medication and enteral formula incompatibilities are more common with the use of acidic pharmaceutical syrups. The most prudent recommendation is to avoid the routine admixture whenever possible, especially for nonaqueous preparations and syrups. In the... 

Phosphorus can be omitted from the nutritional formula of patients receiving PN until the phosphorus level approaches normal (<5 mg/dL). It is prudent to monitor phosphorus concentrations daily and to add phosphorus in small doses once the serum concentration is below 4 mg/dL. Failure to do so can lead to severe hypophosphatemia (see Chap. 49) despite continued renal failure, especially in the patient treated with CRRT. Patients with persistently high serum phosphorus concentrations who have a functional gastrointestinal tract (GIT) can be prescribed phosphate-binding therapy (see Chap. 44) and enteral feedings low in phosphorus to minimize the absorption of exogenous phosphorus. 

A number of early case reports described warfarin resistance in patients taking enteral feeds that contained high levels of added vitamin Kx- These products were then reformulated to contain lower amounts of vitamin Kx, commonly now about 4 to 10 micrograms per 100 mL however, some cases of interactions have still been reported, and one study in children reported that those receiving enteral nutrition (mostly vitamin K enriched formula) required 2.4-fold higher maintenance warfarin doses. Lipid emulsions containing soya oil might contain sufBcient natural vitamin Kx to alter warfarin requirements. Parenteral multivitamin preparations may also contain vitamin Kx. 

A 63-year-old morbidly obese man with Parkinson s disease and type 2 diabetes mellitus was given enteral feeds after multiple trauma, and his medications (pramipexole, entacapone, and immediate-release levodopa+carbidopa) were given via nasogastric tube. When his enteral feeds were changed to a formula that provided... 

Enter similar formulas for the flow rates of grain, water, and ethanol in the reactor feed. 

Anderson KR, Norris DJ, Godfrey LB, et al. Bacterial contamination of the tube-feeding formulas. J Parenter Enter Nuir 1984 8 673-678. 

In inflammatory bowel disease (IBD) high fiber diets have no special part to play in the management of Crohn s disease where enteral feeding (with formula low-residue, low-fiber preparations) is especially beneficial where there is acute extensive small bowel disease. In ulcerative colitis specific dietary advice is usually unnecessary though fiber supplements may be of benefit in patients whose disease is limited to proctitis (inflammation of the rectum). 

Compatibility of medications with an enteral nutrition (EN) formula and, conversely, an enteral nutrition (EN) formula with administered medications is of concern when administering medications through feeding tubes. 

Enteral nutrition (EN) is broadly defined as delivery of nutrients via the gastrointestinal (GI) tract. This could include normal oral feeding as well as delivery of nutrients in a liquid form by a tube. Sometimes when the term enteral nutrition is used, only tube feedings are included hence the terms enteral nutrition and tube feedings are often used synonymously. The bulk of this chapter will include information regarding delivery of feedings via tubes. Formulas for EN usually are delivered in the form of commercially prepared liquid preparations, although some products are produced as powders for reconstitution. 

It might be expected that EN via tubes would have been used widely before the development of parenteral nutrition (PN) however, this was not actually the case. EN via tubes inserted down the mouth or nose into the stomach and also via rectal tubes was used occasionally in the decades before the development of PN in the 1960s.1 However, modern techniques for enteral access, both the placement of the tubes themselves and the materials for making pliable, comfortable tubes, had not yet been developed. Before the PN era, the formulas delivered by the tube route often were blenderized foods. The National Aeronautics and Space Administration effort in the United States in the 1960s led to the development of low-residue (monomeric) diets for astronauts. These diets were adapted for use in sick patients requiring EN. Nonvolitional feedings in patients who cannot meet nutritional requirements by oral intake thus include EN and PN these techniques are collectively known as specialized nutrition support (SNS). 

Diarrhea Drug related Antibiotic-induced bacterial overgrowth Hyperosmolar medications administered via feeding tubes Antacids containing magnesium Malabsorption Hypoalbuminemia/gut mucosal atrophy Pancreatic insufficiency Inadequate GIT surface area Rapid GIT transit Radiation enteritis Tube feeding related Rapid formula administration Formula hyperosmolalty Low residue (fiber) content Lactose intolerance Bacterial contamination... 

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