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Flashcards in Enteral Nutrition Deck (35):

Contraindications for EN

-Inadequate resuscitation or hypotension; hemodynamic instability
-Intestinal obstruction
-Severe GI bleed
-Expected need less than 5-7 days if normally nourished


Conditions that Require EN

-Impaired ingestion
-Inability to consume adequate nutrition orally
-Impaired digestion, absorption, metabolism
-Severe wasting or depressed growth


Advantages of EN vs TPN

-Preserves gut integrity
-Possibly decreases bacterial translocation
-Preserves immunological function of gut
-Reduces costs
-Fewer infectious complications in critically ill pts
-Safer and more cost effective in many settings


Advantages of EN

-Intake easily/accurately monitored
-Provides nutrition when oral is not possible or adequate
-Supplies readily available
-Reduces risks associated with disease state


EN Formula Selection

-Determine best choice by medical and nutrition assessment
-Meet specific nutrition needs


Monomeric EN Formula

-Predigested nutrients
-Free amino acids and/or short peptide chains
-Has low fat content or high percentage of MCT, LCT, structured lipids
-Use in pts with compromised digestive and/or absorptive capacity
-More expensive than standard formulas
-Tend to be more hyperosmolar because of small particle size


Contraindications for EN

-Severe acute pancreatitis
-High output proximal fistula >500ml/day
-Inability to gain access
-Intractable emesis or diarrhea
-Aggressive therapy not warranted


EN Complete Formulas

Enteral formulas designed to supply all needed nutrients when given in sufficient volume. May also be used in smaller quantities to supplement regular diets.


EN Formula Categories

-Fiber containing
-Disease specific


Polymeric EN Formula

-Whole protein nitrogen source
-For use in pts with normal or near normal GI function
-Protein isolate formulas
-Blenderized formulas


Protein Isolate Formulas

Protein that has been separated from a food (casein from milk, albumin from egg).


Rehydration Formula

For pts requiring optimal ratio of CHO to electrolytes to facilitate fluid and electrolyte absorption, rehydration.


Blenderized Formulas

May contain pureed meat, vegetables, fruits, milk, starches with vitamins and minerals added. Can be made at home or purchased commercially.


Open System

-Product is poured into a feeding bag
-Allows modulars such as protein and fiber to be added to feeding formulas
-Less waste in unstable pts
-Shorter hang time
-Increases nursing's time
-Increased risk of contamination


Fiber-Containing EN Formula

Containing a source of fiber; reportedly beneficial for prevention/treatment of altered bowel function in enterally fed pts. Soy polysaccharide is the most common fiber additive in enteral feedings; effectiveness in treating diarrhea in tubed pts unproven.


Formula Selection

The suitability of a feeding formula should be evaluated based on:
-Functional status of GI tract
-Physical characteristics of formula (osmolality, fiber, caloric density, viscosity)
-Macronutrient ratios
-Digestion and absorption capability of pt
-Specific metabolic needs
-Contribution of the feeding to fluid and electrolyte needs or restriction
-Cost effectiveness


Calorie-Dense EN Formula

-May be used in fluid-restricted or volume-sensitive pts
-Useful for nocturnal feedings where nutrition must be delivered over brief time span
-Calorie density range from 1.3-2 kcals/ml
-Monitor fluid/hydration status


Fiber-Containing EN Formula

-Soluble fiber (guar gum, oat, fiber, pectin) may exert trophic effect on colonic mucosa and be useful in normalizing bowel function
-Most enteral feedings in amounts typically used contain less than recommended fiber intake for adults (20-35g)
-Pts with impaired gastric emptying should not be fed fiber-containing formula into the stomach


Disease Specific EN Formula

-Designed for pts with specific disease states
-Available for pts with respiratory disease, ARDS, diabetes, renal failure, hepatic failure, and immune compromise


Hepatic Specific Formula

-Generally have reduced aromatic amino acids and increased branched chain amino acids
-More expensive than standard products
-Often lower in protein than standard formulas (may be too low for most live pts)
-Standard (high protein) products are generally appropriate for pts with liver disease


Renal Specific Formula

-Originally developed in an effort to delay the need for dialysis as long as possible
-Typically are calorie dense (2.0 kcal/ml)_ products with relatively low protein levels and modified electrolytes
-Generally too low in protein for dialyzed pts and acutely ill pts
-May be useful for short term use as supplement or calorie source in pre-dialysis chronic renal failure pts


Immune Enhancing Formula

-Have added "immune-enhancing" nutrients (arginine, glutamine, omega-3 fatty acids, nucleotides)
-Meta-analysis suggests that they might be most beneficial in surgical pts


Modular Formula

Provides protein, fat, or CHO as single nutrients or modular mixtures to allow adjustment of macronutrient mix. May also contribute to renal solute load, osmolality.


EN Formula CHO Source

-CHO content ranges from 40-90% of total calories
-Typically some combination of hydrolyzed cornstarch, maltodextrins, corn syrup solids, sucrose
-Fructooligosaccharides (FOS)
-Fiber: soy polysaccharide (most common)


Fructooligosaccharide (FOS)

Poorly absorbed in the small intestine, fermented in the large intestine, may promote growth of healthy bacteria.


EN Formula Lipid Source

-Fat provides isotonic, concentrated energy source
-Corn and soybean oil common
-Also safflower, canola, fish oil
-May include MCTS; more easily digested and absorbed
-Fat content ranges from 50% of calories


EN Formula Protein Source

-Whole protein, hydrolyzed protein, free amino acids
-Casein, soy protein, lactalbumin, whey, egg white albumin
-Small peptides absorbed as efficiently as free amino acids
-Free amino acids are more hyperosmolar



Conditionally essential amino acid with immune-enhancing properties. Research suggest some benefit in wound healing. Recent research suggest may be harmful in septic pts.



May enhance small intestine growth and repair.


Closed System

-Containers are sterile until spiked for hanging
-Can be used for continuous or bolus delivery
-No flexibility in formula additives
-Less nursing time
-Increases safe hang time
-Less risk of contamination
-More expensive than canned formula


Branched-Chain Amino Acids

-Thought to prevent or treat hepatic encephalopathy and prevent muscle catabolism
-BCAA sometimes recommended for refractory encephalopathy.


Pulmonary Formula

-Contain higher percentage of total calories from fat to reduce respiratory quotient and make it easier to wean from respirator
-However, total calorie intake has more impact on respiratory function than formula composition
-High fat gastric feedings may cause delayed emptying in critically ill pts


Enteral Nutriton

Nutritional support via tube placement through the nose, esophagus, stomach, or intestines (duodenum or jejunum). Must have functioning GI tract and exhaust all oral diet methods first.


Conditions that Require TPN

-GI incompetency
-Hypermetabolic state with poor enteral tolerance or accessibility


Disadvantages of EN

- GI, metabolic, and mechanical complications- tube migration; increased risk of bacterial contamination; tube obstruction; pneumothorax
-Costs more than oral diets
-Less "palatable/normal"
-Labor intensive assessment, administration, tube patency and site care monitoring