Enteral and Parenteral Nutrition Flashcards
When is it acceptable to use parenteral nutriton?
- Enteral nutrition is better than parenteral nutrition
- in pts with no nutritional deficiencies, no nutrition is better than enteral
How many kcal in 1 gram of protien?
4 kcal
How many kcal in 1 gram of dextrose?
3.4 kcal
How many kcal in 1 gram of fat?
9 kcal
What are indications for enteral nutrition?
- hemodynamically stable pt at risk of malnutrition
- oral feedings will be inadequate for several days
What are contraindication for enteral nutrition? (6)
- complete intestinal obstruction
- GI fistula
- extreme short bowel
- severe diarrhea or vomiting
- hemodynamic instability or intestinal ischemia (not enough blood to the intestine)
- paralytic ileus (inablility to move food through GI because of paralytic activity)
What are the advantages of enteral over parenteral?
- maintain gut integrity
- prevent stress ulceration
- improves outcomes
- more physiologic
- less costly
- less risk of infection
What are the six types of feeding tubes?
- orogastric- mouth to stomach
- nasogastric- nose to stomach
- nasoduodenal- from the nose to the duodenum
- nasojejunal- through the nose and into the jejunum
- gastrostomy- opening in the stomach
- jejunostomy- surgical opening in the jejunum
When would you use a nasogastric (NG) tube?
- short term
- prolong use can cause sinusitis or nasal mucosal ulceration
- cannot use in pt with gastric ileus
What are the pros and cons of nasoduodenal/nasojejunal?
- smaller and more flexible than NG tubes
- easier to clog, required continuous infusion feeds
What is a PEG tube?
Percutaneous endoscopic gastrostomy
When would you perform a gastrostomy?
- Long term use
- PEG requires continuous infusion of feeds
When would you perform a jejunostomy?
- long term use
- facilitate immediate postoperative or post injury feeding
Why would would opt for an enteral feeding pump in a hospital?
- reduced risk of aspiration compared with bolus feedings
- cyclic feeding are administered for 10-12 hours overnight to allow for mobility during the daytime
What is usually in an enteral formula?
- contains carbohydrates, fat, protien, electrolytes, water, vitamin, and trace elements
- ex: ploymeric, monomeric (elemental), disease specific, modular
What are the specifics of polymeric (intact) enteral formulas?
- formulas are used in patients with normal digestive process
- contain 1-1.2 kcal/mL
- generally inexpensive
- some formulas are concentrared for patients requiring fluid restriction and contain 2 kcal/ML
What are the specifcs of monomeric (elemental) enteral formulas?
- easily digested for pts with impaired digestive capacity or malabsorption
- more expensive than polymeric EN
What are the disease specific EN formulas?
- renal formulas (magnacal renal)
- pulmonary formulas (pulmocare)
- diabete formulas (glucerna)
- hepatic formulas (NutriHep)
What does an EN renal formula consist of?
- concentrated (2 kcal/mL)
- low protein formula for non-dialysis pts
- high protein formula for dialysis pts
What does an EN pulmonary formula consist of?
- more calories from fat to reduce CO2 production
- facilitate vent weaning
- controversial and expensive
What does an EN diabetic formula consist of?
Low sugar, extra fiber
What does an EN hepatic formula contain (ingredient)?
more branched chain AA less aromatic AA
may improve encephalopathy
What is in the modular enteral nutrition formula?
- Carbohydrate (Polycose)
- Protein powder (ProSource)
- Fat (corn oil, MCT Oil)
What are the complications to enteral feeding?
- Improper tube placement
- clogged feeding tubes (flush feeding tube with warm water, soda, pancreatic enzymes, or bicarb)
- aspiration pneumonia (keep head elevated, gastric residual monitoring possibly effective, start at a slow rate)
- diarrhea
- constipation can be prevented by adding fiber or metoclopramide
- dehydration
- hypernatremia occurs when pts are given insufficient water (1mL of water per calorie)
How does one develop an enteral feeding regimen?
- Determine caloric requirements
- Choose forumla and asses the calories per milliliter
- Determine infusion rate
- Make sure patient will receive enough protein
- Make sure patient will receive about 1 mL of water each calorie
How do you determine carloric requirements?
25-30 kcal/kg/day or use Harris Benedict equation
What are the options for EN formula concentration?
1, 1.2, 1.5, or 2 kcal/mL
How do you determine the infusion rate?
(volume of EN) / 24 hours
How do you administer drugs through an ET tube?
- use liquids diluted with 2-3 times the medication volume
- diarrhea can happen with drugs that have high osmolality
- flush with 20mL of water
- do not crush SR or enteric coated pills
- discontinue tube feedings before and after drug admin temp
- consider feeding tube locatio and subsequent drug absorption
When would you opt for parenteral nutrition?
IV nutrition indicated in pts with nonfunctioning or inaccesible GI tract if pt cannot be fed enteraly for 7 days
What is TPN?
- Total parenteral nutrition
- administered through central line
- IV catheter where the tip is in the vena cava or adjacent to the right atrium
- ex: PICC– peripherally inserted central catheter
Whar is PPN?
- peripheral parenteral nutrition
- administered through peripheral line
- won’t give everything the person requires but better than nothing
What are the types of PN?
- 2-in-1 – amino acids and dextrose in one bag- liquids infused separately (increased risk of bacterial growth in lipids)
- 3-in-1– dextrose + amino acids + lipids
What are the benefits and disadvantages of 3-in-1 PN formulation?
- nutrients all mixed in the same bag
- stability dependent on final concentration of amino acid
- acidic enviornment limits bacterial growth
- shorter stability
- cannot inspect for precipitates
When components must be considered when developing a regimen?
- dextrose 70% is commonly used as a carb source (70% = 70 grams in 100mL– 1 gram =3.4 kcal)
- fat emulsion 10%, 20%, 30%
- 20% is most commonly used– available as 250mL that provide 2kcal/mL
- should be 20-30% of total calories
- amino acid 15% is commonly used – 1g amino acid = 4 kcal
- electrolytes added to maintain physiologic serum concentrations
- multivitamins and trace elements supplemented
How do you develop a parenteral feeding regimen?
- determine caloric requirements
- determine fluid requirements (1500mL for first 20kg with 15-20mL/kg additional)
- determine protien requirements (0.8 to 2.5g/kg/day– use ideal body weight)
- subtract calories from protein (20-30% total calories from lipid emulsion and remainder from dextrose)
* max dextrose infusion rate of 4-6 mg/kg/min
* max lipid infusion rate of 0.1g/kg/hr
What can be used for daily maintenance amount of electrolytes, vitamins and trace elements?
- sodium and potassium can be given as chloride or acetate
- chloride can cause acidosis, useful in pts with alkalosis
- acetate converted into bicarb– useful in metabolic acidosis
- parenteral multivitamin should be added daily (additional thiamine supplemented in pts with alcohol use)
What is in tralement?
- selenium
- copper
- manganese
- zinc
When would you need to use tralement?
- pt with high-output fistulas, diarrhea, burns, or open wounds may need zinc supplementation
- pt with chronic diarrhea, malabsorption and short-gut syndrome may require additional selenium supplementation
- pt with severe cholestasis should have copper and manganese restricted to prevent accumulation and toxicity because both undergo biliary elimination
What are possible complications of PN?
- calcium and phosphate precipitation (use calcium gluconate; more acidic increases solubility)
- many meds are incompatible with TPN
- risk of catheter related infection
- acid-base abnormalities (mitigated through changing from acetate to chloride salts)
- hyperglycemia (treated with insulin outside of TPN)
- overfeeding
- gut atrophy
- aluminum toxicty (long term PN use in pt with renal dysfunction– brittle bones and encephalopathy
- refeeding syndrome
- hypertriglyceridemia
What are conclusions that can be made about parenteral and enteral feeding?
- enteral is preferred if it can be safely done
- PPN can’t deliver adequate calories and nutrients
- process for constructing a TPN regimen that meets the nutritional need of the pt
