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  1. Nutrition & Diet Therapy (7th Edition) Specialized Nutrition Support: Enteral & Parenteral Nutrition Chapter 16
  2. Nutrition & Diet Therapy (7th Edition) Need for Nutrition Support • Nutrition support may be required to meet patient’s nutritional needs – Patients often too ill to obtain energy & nutrients by consuming foods – Or illness may interfere with eating, digestion or absorption • Nutrition support: delivery of formulated nutrients by feeding tube or intravenous infusion • Enteral nutrition: supplying nutrients using GI tract, including tube feedings & oral diets • Parenteral nutrition: intravenous provision of nutrients, bypassing the GI tract
  3. Nutrition & Diet Therapy (7th Edition) Selecting a Feeding Route
  4. Nutrition & Diet Therapy (7th Edition) Enteral Nutrition Support • Wide selection of enteral formulas, designed to meet variety of medical & nutritional needs • May be used alone or in conjunction with other foods • Many formulas can provide all of nutrient requirements if consumed in sufficient volume • Classified according to macronutrient composition • Preferred over intravenous feedings Enteral nutrition requires intact & normal GI function
  5. Nutrition & Diet Therapy (7th Edition) Types of Enteral Formulas • Standard formula: for patients who can digest & absorb nutrients without difficulty; contains protein & carbohydrate sources • Hydrolyzed formulas: used for patients with compromised digestive or absorptive functions— macronutrients are partially or fully broken down & require little, if any, digestion before absorption • Disease-specific formulas: designed to meet nutrient needs of patients with particular disorders: liver, kidney, lung diseases, glucose intolerance, metabolic stress • Modular formulas: contain only one or two macronutrients; used to enhance other formulas
  6. Nutrition & Diet Therapy (7th Edition) Enteral Nutrition in Medical Care • Oral use – Supplement diet when food consumption does not meet need – Reliable source of nutrients & energy – Taste important consideration • Tube feedings – Used when patient cannot consume enough food or formula orally – Feeding delivered directly to stomach or intestine • Patients can drink enteral formulas when they are unable to consume enough food from a conventional diet
  7. Nutrition & Diet Therapy (7th Edition) Enteral Nutrition in Medical Care (con’t) • Candidates for tube feedings: – Severe swallowing difficulties – Little or no appetite for extended periods, especially if malnourished – GI obstructions, impaired motility of the upper GI tract – After intestinal resection, beginning enteral feedings – Mentally incapacitated due to confusion, dementia, neurological disorders – Individuals in coma – Individuals with extremely high nutrient requirements – Individuals on mechanical ventilators
  8. Nutrition & Diet Therapy (7th Edition) Enteral Nutrition in Medical Care (con’t) • Feeding routes – Selected on basis of medical condition, expected duration, potential complications of a particular route – Main routes: • Transnasal (temporary) – Nasogastric – Nasoduodenal – Nasojejunal • Gastrostomy • Jejunostomy
  9. Nutrition & Diet Therapy (7th Edition) Enteral Nutrition in Medical Care (con’t) • Formula selected after assessment of the diagnosis, patient’s age, medical problems, nutritional status, ability to digest & absorb nutrients • Nutrition-related factors influencing formula selection – Energy, protein & fluid requirements – Need for fiber modifications – Individual tolerances (food allergies & sensitivities)
  10. Nutrition & Diet Therapy (7th Edition) Enteral Nutrition in Medical Care (con’t) • Administration of tube feedings – Safe handling • Open feeding system • Closed feeding system • Safety guidelines – Review of procedure with patient & family – Verification of tube placement (Xray) – Formula delivery • Intermittent feedings (bulk over 20-40 min) • Continuous feedings (pump) • Bolus feeding (one or several “shots”) • Open feeding system: requires formula to be transferred from original packaging to feeding container • Closed feeding system: formula prepackaged in ready-to-use containers • Intermittent feeding: delivery of prescribed volume over 20- 40 minutes • Continuous feeding: slow delivery at constant rate over 8-24 hour period • Bolus feeding: delivery of prescribed volume in less than 15 minutes
  11. Nutrition & Diet Therapy (7th Edition) Enteral Nutrition in Medical Care (con’t) • Formula volume & strength – Procedures vary by institution – Almost all patients can receive undiluted isotonic or hypertonic formulas – Generally started slowly and volume gradually increased • Rate & amount of increase depend on patient’s tolerance • Continuous feedings may be better tolerated than intermittent feedings • Checking gastric residual volume (vol. of formula in stomach after fdg.) – Volume of formula remaining in stomach from previous feeding – Evaluate if gastric residual >200 mL – If tendency to retain persists, physician may consider intestinal feedings or drug therapy to stimulate gastric emptying
  12. Nutrition & Diet Therapy (7th Edition) Enteral Nutrition in Medical Care (con’t) Meeting water needs • Adults require about 2000 mL of water daily – Fluid intake may be restricted for patients with kidney, liver or heart disease – Fluid intake may be increased with fever, high urine output, diarrhea, excessive sweating, severe vomiting, fistula drainage, high-output ostomies, blood loss, open wounds • Standard formulas contain about 85% water (about 850 mL/liter); nutrient-dense formulas contain about 69-72% water • Meet fluid needs with additional water flushes Estimating fluid requirements Adults: 30-40 mL/kg; 30 mL/kg for older adults Children: 50-60 mL/kg Infants: 150 mL/kg
  13. Nutrition & Diet Therapy (7th Edition) Enteral Nutrition in Medical Care (con’t) • Transition to table foods – Volume of formula is tapered off as condition improves – Gradual shift to oral diet • Begin drinking same formula that is delivered by tube • Oral intake should supply about 2/3 of nutrient needs before tube feedings discontinued
  14. Nutrition & Diet Therapy (7th Edition) Enteral Nutrition in Medical Care (con’t) • Giving Medication through feeding tubes – Potential for diet-drug interactions must be considered before administration – Continuous feeding halted for approximately 15 minutes before & 15 minutes following medication delivery (longer for some medications) – Type of medication may make tube administration impossible—require change to alternate route • Generally best to administer medications by mouth whenever possible
  15. Nutrition & Diet Therapy (7th Edition) Enteral Nutrition in Medical Care (con’t) • Complications of tube feedings – Gastrointestinal problems: nausea, diarrhea – Mechanical problems related to tube feeding process – Metabolic problems: biochemical alterations & nutrient deficiencies • Many complications preventable with appropriate feeding route, formula & delivery method • Close attention to patient’s medical condition & medication use is important (follow up/reassessment) – Monitor weight, hydration status – Verify lab test results
  16. Nutrition & Diet Therapy (7th Edition) Parenteral Nutrition Support • Indicated for patients who do not have functioning GI tract & who are malnourished (or likely to become so) • Used when enteral formulas cannot be used or intestinal function is inadequate • Life-saving option for critically-ill persons • Two main access sites: central or peripheral vein Indications – Short-bowel syndrome – Severe pancreatitis – Malabsorption disorders – Intestinal obstruction or fistula – Severe burns or trauma – Critical illnesses or wasting disorders – Bone marrow transplant – Malnourished with high risk for aspiration
  17. Nutrition & Diet Therapy (7th Edition) Venous Access • Peripheral parenteral nutrition (PPN) – Can only provide limited amounts of energy & protein – Peripheral veins can be damaged by overly concentrated solutions – Limited to patients who do not have high nutrient needs or fluid restrictions – Used most often for short-term nutrition support (7-10 days) – Rotation of vein sites may be necessary
  18. Nutrition & Diet Therapy (7th Edition) Venous Access (con’t) • Total parenteral nutrition (TPN) – Can reliably meet complete nutrient requirements – Provides nutrient-dense solutions for patients with high nutrient needs or fluid restrictions – Preferred for long-term intravenous feedings – Inserted directly into a large central vein
  19. Nutrition & Diet Therapy (7th Edition) Parenteral Solutions • Customized formulations to meet patients’ nutrient needs • Highly individualized; often recalculated on daily basis until patient’s condition stabilizes • Contents: – Amino acids (both essential and non-essential for protein) – Carbohydrates (dextrose) – Lipid emulsions – Fluid & electrolytes – Vitamins & trace minerals
  20. Nutrition & Diet Therapy (7th Edition) Administering Parenteral Nutrition • Multidisciplinary nutrition support team of health care professionals – Physicians – Nurses – Dietitians – Pharmacist • Potential complications related to venous line & metabolic problems
  21. Nutrition & Diet Therapy (7th Edition) Administering Parenteral Nutrition (con’t) • Administration procedures – Insertion & care of intravenous catheters – Administration of parenteral solutions • Continuous administration -24 hours/day • Cyclic administration – 10 to 16 hour periods – Monitoring patient condition, nutritional status, complications – Discontinuing of feedings-when GI function returns
  22. Nutrition & Diet Therapy (7th Edition) Nutrition Support at Home • Continuation of nutritional support (tube feedings or parenteral nutrition) after medical condition has stabilized • Candidates for home nutrition support – Long-term nutrition care required for chronic conditions – Users intellectually capable of learning procedures, monitoring treatment & managing complications • Planning for home nutrition – Involvement of users in decision making to ensure long- term compliance & satisfaction – Assessment & evaluation of type of feeding, equipment, resources, ability to perform procedures
  23. Nutrition & Diet Therapy (7th Edition) Nutrition Support at Home (con’t) • Quality of life issues – Lifestyle adjustments may cause struggle for patients & families – Economic impact – Time & other demands associated with treatment – Physical difficulties, including disrupted sleep – Social issues – Life-sustaining therapy associated with serious complications • Portable pumps & convenient carrying cases allow people who require home nutrition support to move about freely
  24. Nutrition & Diet Therapy (7th Edition) Nutrition in Practice—Inborn Errors of Metabolism • Inborn error of metabolism: inherited trait, caused by genetic mutation • Results in absence, deficiency or malfunction of a protein that has a critical metabolic role
  25. Nutrition & Diet Therapy (7th Edition) Nutrition in Practice—Inborn Errors of Metabolism (con’t) • Medical nutrition therapy is primary treatment for many inborn errors that involve nutrient metabolism • Dietary intervention generally involves restriction of substances that cannot be metabolized or supplying substances that cannot be produced • Dietary changes may improve outcomes – Preventing accumulation of toxic metabolites – Replacing deficient nutrients – Providing a diet that supports normal growth & development & maintains health • Some inborn errors may require treatment other than or in addition to dietary changes
  26. Nutrition & Diet Therapy (7th Edition) Nutrition in Practice—Inborn Errors of Metabolism (con’t) • Phenylketonuria (PKU) – Metabolic disorder affecting amino acid metabolism – Missing or defective protein is liver enzyme that converts the essential amino acid phenylalanine to tyrosine – Phenylalanine & metabolites accumulate and damage developing nervous system—most debilitating effect is on brain development – Diagnosed within first few days following birth—infants routinely screened in all 50 states – Treatment consists of lifelong diet restricting phenylalanine & supplying tyrosine; allowing blood levels of these amino acids to be maintained within safe ranges
  27. Nutrition & Diet Therapy (7th Edition) Nutrition in Practice—Inborn Errors of Metabolism (con’t) • Managing PKU – Central to PKU diet is enteral formula that is phenylalanine-free & supplies energy, amino acids, vitamins & minerals – Formula requirements must be recalculated periodically to accommodate growing infant’s shifting needs for protein, phenylalanine, tyrosine & energy • Careful monitoring of foods containing phenylalanine • Monitoring of growth rates & nutrition status – Parents & children may need to develop creative ways to make diet enjoyable
  28. Nutrition & Diet Therapy (7th Edition) Nutrition in Practice—Inborn Errors of Metabolism (con’t) • Galactosemia – Inborn error of carbohydrate metabolism – Deficiency of enzyme needed to metabolize galactose – Accumulation of galactose can result in damage to multiple tissues • Reaction with severe vomiting & jaundice within days of initial feeding of infant • Serious liver damage may result, progressing to symptomatic cirrhosis • Other complications: kidney failure, cataracts, brain damage – Delay in treatment can result in irreversible brain damage
  29. Nutrition & Diet Therapy (7th Edition) Nutrition in Practice—Inborn Errors of Metabolism (con’t) • Managing galactosemia – Main focus of diet is exclusion of milk & milk products (elimination of galactose) – Avoidance or restriction of other galactose- containing foods • Organ meats • Some legumes, fruits & vegetables – Food lists help patients to identify galactose content of common foods – Complications may develop despite compliance with diet therapy