Enteral & Parenteral Nutrition Support Chapter 15 Enteral & Parenteral Nutrition Support © 2007 Thomson - Wadsworth

Nutrition Support Enteral Parenteral Uses the veins Means “within or by means of the gastrointestinal tract.” Oral Known as tube feedings Preferred route if have adequate GI function Parenteral Uses the veins Persons with inadequate GI function The consensus of nutrition experts is that the GI tract is more physiologically and metabolically effective than the intravenous route for nutrient utilization. Once the patient has been assessed and found to be a good candidate for enteral nutrition, the clincian selects the appropriate tube and route of access for tube placement. Enteral access selection depends on several factors: Anticipated length of time enteral feeding will be required Degree risk for aspiration or tube displacement Presence or absence of normal digestion and absorption Whether or not there is a planned surgical intervention © 2007 Thomson - Wadsworth

Algorithm for enteral vs parenteral selection. © 2007 Thomson - Wadsworth

If you choose enteral nutrition support… Must have functional GI tract Bowel sounds Can be used alone or as a supplement Variety of kinds of formulas Types Standard (1.0-1.2cal/ml) Tolerated by most patients Hydrolyzed Partially or fully broken down Persons with compromised GI functioning High calorie Disease-specific Modular contain 1-2 macronutrients A wide variety of enteral feeding products are commercially available. It takes a complex nutritional assessment to determine what type of formula a patient needs. As more products become available, with claims for pharmacologic effects, clinical trial evidence for each new product must be carefully evaluated by the clinician before a decision is made to use a formula. In 3 studies conducted on patients in the CCU, it was found that physician ordered TF rates met 11-120% of the patients needs. Of the ordered rates patients only received 76-78% of the expected amount of TF. Formulas are classified in a variety of ways, usually based on protein or overall macronutrient composition. - General purpose: tolerated by most patients, usually have 1.0 – 1.2 calories per mL - High calorie: General formula with 1.5-2.0 calories per mL. Used when it is necessary to restrict fluid for patients with cardiopulmonary, renal and hepatic failure. - Hydrolyzed: Used for those patients who have malabsorptive problems - Disease-specific: Available for patients who have renal, hepatic, or cardiopulmonary disease; metabolic stress, immunosuppression or glucose intolerance. The use of these types of formulas is controversial. © 2007 Thomson - Wadsworth

Enteral Nutrition Support Provide Pro, CHO and Fat Nutrient Density Protein = 8-29% of total kcalories Standard formulas Carbohydrates = 40-50% total kcalories Fat = 30-45% total kcalories Energy Density 0.5-2.0 kcalories per mL Standard formulas 1.0-1.2 kcalories per mL Patients with average fluid requirements Formulas with higher energy density Smaller amount of fluid Good for fluid restrictions Protein in enteral formulas provides 8-29% of total calories. Typically TF provide polymeric forms of protein (whole proteins) but a TF formula can also contain amino acids which are derived from hydrolysis of casein, whey, lactoalbumin, or soy. These are for patients with maldigestion or malabsorption. Osmolalities will be higher in these formulas because of the hydrolyzed proteins. Carbohydrates contribute 40-50% of total calories. Lactose is not used as a carbohydrate source in most formulas because of the high incidence of lactase deficiency in acutely ill patients. Lipids provide 30-45% of total calories. Total calories provided by lipids is usually from corn, soy, sunflower, or safflower oils. Pulmonary formulas are typically high fat formulas intended to prevent excess carbon dioxide retention and facilitate weaning from mechanical ventilation. © 2007 Thomson - Wadsworth

Feeding Routes Tube feeding less than 4 weeks Postplorically Nasogastric Postplorically Nasoduodenal Nasojejunal These tubes are weighted or non-weighted with stylets to guide placement Orogastric Mouth to stomach Good for vent patients Tube feeding more than 4 weeks Enterostomy Gastrostomy Jejunostomy Gastric feedings are the preferred route Easily tolerated & less complicated Not good for patients at risk for aspiration Nasogastric, nasoduodenal or nasojejunal routes are for short-term use of 3 to 4 weeks, a NGT passed through the nose into the stomach is appropriate. Patients with normal GI function and gag reflex tolerate this method, which takes advantage of normal digestive, hormonal, and bactericidal processes in the stomach. - Feedings can be administered by bolus injection or intermittent or continuous infusion. NGT is made of a soft, flexible, and well-tolerated polyurethane or silicone tube of various diameters, lengths, and design features may be used, depending on formula characteristics and feeding requirements. - For example: A thicker formula is going to need a larger diameter tube. The lumen (space inside the tube) is measured by the french unit. 1 french = .3mm If a tube is placed post-pylorically, what does this mean? Percutaneous endoscopic gastrostomy (PEG) tube is a nonsurgical technique for placing a tube directly into the stomach through the abdominal wall, performed using an endoscope and with the patient under local anesthesia. Tubes are endoscopically guided into the stomach or the jejunum and then brought out through the abdominal wall to provide the access route for enteral feedings. Preferred method if feeding is estimated to last >3-4 weeks. It is possible to place a percutaneous endoscopic jejunostomy (PEJ) tube percutaneously, however, this procedure carries a higher degree of risk. NGT placement is verified by aspirating gastric contents, pushing air into the stomach, or radiographic confirmation of the tube tip location. When soft, small-bore tubes are used, aspiration of gastric contents must be performed cautiously to prevent the tube from collapsing. © 2007 Thomson - Wadsworth

© 2007 Thomson - Wadsworth

© 2007 Thomson - Wadsworth

Osmolality A solution’s tendency to shift from one fluid compartment to another across a semipermeable membrane Range: 300-700 milliosmoles per kilogram Isotonic: osmolality similar to blood Hypertonic: osmolality greater than blood The size and number of the nutrient particles in a solution define its osmolality. General purpose formulas have osmolalities between 300-700 mOsm, which is close to the osmolality of body fluids. Osmolalties of nutrient-dense formulas are higher, ranging from 400-700 mOsm. Hydrolyzed formulas are as high as 900 mOsm per kg of water. © 2007 Thomson - Wadsworth

Enteral Nutrition in Medical Care Preferred over parenteral Helps maintain gut Fewer complications Less costly Oral preferred over tube feedings Less stress Less complications Can fully meet nutrient needs Good for weak & debilitated patients Nurses help patients find appealing flavors © 2007 Thomson - Wadsworth

Candidates for Tube Feedings Severe swallowing problems Little or no appetite GI obstructions, impaired GI motility Intestinal resections Mentally incapacitated Coma Extremely high nutrient requirements Mechanical ventilators © 2007 Thomson - Wadsworth

Feeding Tubes Soft & flexible Variety of lengths & diameters Outer diameter measured in French units © 2007 Thomson - Wadsworth

Formula Selection Need to assess Choose the one Age Medical problems Nutritional status Ability to digest & absorb nutrients Choose the one With the lowest risk of complications Lowest cost Nutrition-related factors Energy, protein, & fluid requirements Need for fiber modification Individual tolerances (food allergies & sensitivities) © 2007 Thomson - Wadsworth

Algorithm for enteral formula selection. © 2007 Thomson - Wadsworth

What Formula? Factors to consider Electrolytes GI function Fluid Calorie and protein density Ability to meet needs Type of Protein, fat, CHO Fiber Electrolytes Fluid Viscosity Osmolality © 2007 Thomson - Wadsworth

Administration of Tube Feedings Safe handling Clean equipment Clean hands Open system Formula needs to be transferred from original packaging to feeding container Closed system Formula is prepackaged Safety guidelines Clean can opener & lid Refrigerate unused portions in clean, closed containers Discard unlabeled or unused within 24 hours Open system; hang no longer than 8-12 hour supply Closed system; hang no longer than 24-48 hour supply © 2007 Thomson - Wadsworth

Tube Feeding Formula delivery Initiating tube feeding Intermittent Formula delivery Intermittent Gastric, 2500-400 mL over 20-40 minutes Risk of aspiration Bolus Gastric Delivery of <500mL every 3-4 hours Continuous Slowly at constant rate 8-24 hours Noctural Initiating tube feeding Discuss with patient & family Check initial placement with X-ray Monitor its position throughout the day: can check fluid pH The three common methods of tube feeding administration are bolus, intermittent drip, and continuous drip. Method selection is based on the patient’s clinical status and quality of life considerations. One method can serve as a transition to another method as the patient’s status changes. Bolus – The feeding modality of choice when patients are clinically stable with a functional stomach is the syringe bolus method. Syringe bolus feedings are more convenient and less expensive than pump or gravity bolus feedings and should be encouraged when tolerated. The pt with normal gastric function can usually tolerate up to 500mL of formula at each feeding. Three or four feedings per day can provide the daily nutritional requirements for most pts. Intermittent – All more free time compared to continuous drips. A schedule is based on four to six feedings per day administered for 20 to 40 minutes. Formula administration is initiated at 100 to 150 mL per feeding and increased incrementally as tolerated. Intermittent feedings as well as bolus feedings should not be used with patients at risk for pulmonary aspiration. Continuous – Requires a pump. This method is appropriate for pts who do not tolerate large-volume infusions such as those occurring with bolus or intermittent methods. Patients with small bowel access should be fed by continuous drip infusion. The feeding-rate goal, in mL per hour, is set by dividing the total daily volume by the number of hours per day of administration. Feeding is started at one quarter to one half the goal rate and advanced every 8 to 12 hours to the final volume. Formulas with osmolalities between 300 and 500 can be started at full strength. © 2007 Thomson - Wadsworth

Administering the Feeding Formula volume & strength Varies among institutions Hypertonic fluids usually started slowly & volume gradually increased Assess patient tolerance Checking gastric residuals Withdraw contents through feeding tube with syringe Intermittent before each feeding Continuous every 4-6 hrs © 2007 Thomson - Wadsworth

Tube Feedings Supplemental water Transition to table foods Formulas are 69-85% water More water comes from flushes via feeding tubes Flush before & after each bolus or intermittent feeding Flush every 4 hours for continuous Count as intake Transition to table foods Gradually shift to oral diet Oral needs to be 2/3 of nutrient intake before discontinuing the tube Fluid needs for adults can be estimated at 1 ml of water/kcal or 30 to 35mL per kg of usual body weight. © 2007 Thomson - Wadsworth

Tube Feedings Delivering medications Complications Monitor patient’s Need to consider diet-drug interactions Medications can clog tubes Continuous: stop feeding 15 minutes before & after medication administration Complications Nausea & diarrhea Mechanical problems Metabolic problems Monitor patient’s Weight Hydration status Lab test results Dilantin Access problems Administration Problems Gastrointestinal complications - N/V - Delayed gastric emptying - Constipation/Diarrhea - High Gastric Residuals Metabolic Complications - Refeeding syndrome - Drug-nutrient interactions - Glucose intolerance - Hydration status © 2007 Thomson - Wadsworth

Parenteral Nutrition Support © 2007 Thomson - Wadsworth

Indications for Parenteral Nutrition Short bowel syndrome Severe pancreatitis Malabsorption disorders Intestinal obstructions or fistulas Severe burns or trauma Critical illnesses or wasting disorders Bone marrow transplants Malnourished & high risk for aspiration © 2007 Thomson - Wadsworth

Venous Access Peripheral Parenteral Nutrition (PPN) Peripheral veins Short-term support Patients with average nutrient needs & no fluid restrictions Veins can be damaged Need solutions under 800-900 mOsm Total Parental Nutrition (TPN) Larger, central veins Long-term support Patients with high nutrient needs or fluid restrictions Peripheral access refers to catheter tip placement in a small vein typically in the arm. May clinicians do not use PPN because they argue that it is short-term therapy with minimal impact on nutritional status. Nutrient solutions not exceeding 800-900 mOsm per kilogram of solvent can be infused through a routine periperhal intravenous catheter placed in a vein in good condition. Central access refers to catheter tip placement in a large, high-bloodflow vein such as the superior vena cava; this is TPN. © 2007 Thomson - Wadsworth

© 2007 Thomson - Wadsworth

Parenteral Solutions Contain amino acids Contain carbohydrates All essential plus combinations of non-essential Contain carbohydrates Dextrose, 3.4 kcalories/gram 2.5-70% concentrations >10% only for TPN Contain lipids Significant source of energy 10, 20% solutions Often provided daily & = 20-30% total kcalories Decreases risk of hyperglycemia from dextrose The concentration of amino acids in these solutions range from 3 to 15% The caloric content of aa is ~ 4 calories per gram. CHO is supplied as dextrose monohydrate in concentrations ranging from 2.5 to 70%. The dextrose monohydrate yields 3.4cal/gm. Lipids emulsions, available in 10% to 20% concentrations are composed of aqueous suspensions of soybean or safflower oil with egg yolk as the emulsifier. A 10% solution provides 1.1 kcals/ml and a 20% solution provides 2.0 kcals/ml. © 2007 Thomson - Wadsworth

© 2007 Thomson - Wadsworth

Parenteral Solutions Fluid Contain electrolytes Contain vitamins Need 1500-2500 mL/day for adults Contain electrolytes Sodium, potassium, chloride, calcium, magnesium, & phosphorus Expressed in milliequivalents (mEq) Contain vitamins All water-soluble plus A, D, & E K must be added separately Contain trace minerals Zinc, copper, chromium, selenium, & manganese Iron is excluded © 2007 Thomson - Wadsworth

Types of Parenteral Solutions Total Nutrient Admixture (TNA) 3-in-1 solution Also called “all-in-one” solution Contains dextrose, amino acids, & lipids 2-in-1 solution Dextrose & amino acids Lipids administered separately to provide essential fatty acids © 2007 Thomson - Wadsworth

Administering Parenteral Nutrition Team effort Physicians Dietitians Pharmacists Nurses: provide direct care IV catheters Nurse can place in peripheral veins Physician must place in central veins Problems Dislodging Air embolism Clotting Phlebitis Infection Must use aseptic technique © 2007 Thomson - Wadsworth

Parenteral Nutrition Complications Mechanical complications Infection and sepsis Metabolic Complications Gastrointestinal Complications Mechanical – pneumothorax, air embolism, blood clotting , catheter dislodgement Infection and sepsis Metabolic – Refeeding syndrome, electrolyte imbalances, glucose GI – Cholestatis, hepatic abnormalities, GI villous atrophy © 2007 Thomson - Wadsworth

Parenteral Solutions Administering Discontinuing Continuous Cyclic Critically ill Malnourished Cyclic 10-16 hours Often provided at night Check tubing & solution daily for contamination Discontinuing When 2/3-3/4 of nutrient needs are provided by enteral feedings, IV can be discontinued Clear liquids Small enteral feedings to determine tolerance © 2007 Thomson - Wadsworth

Managing Metabolic Complications Hyperglycemia Patients who are glucose intolerant or in severe metabolic stress Provide insulin with feedings or decrease dextrose Hypoglycemia When feedings are interrupted or discontinued Taper slowly Hypertriglyceridemia Critically ill can’t tolerate lipid infusions Impaired lipid clearance Refeeding syndrome Re-feed slowly Life-threatening Abnormal liver function Long-term, can lead to liver failure Cause unclear © 2007 Thomson - Wadsworth

Managing Metabolic Problems Gallbladder disease Parenteral for more than 4 weeks Sludge builds up, leading to gallstones Cholecystokinin injections or remove gallbladder Metabolic bone disease Long-term parenteral lowers bone density Alterations in calcium, phosphorus, & vitamin D metabolism © 2007 Thomson - Wadsworth

Nutrition Support at Home Candidates Enteral Head & neck cancers Neurological impairments affecting swallowing Parenteral Portion of small intestine removed Intestinal obstructions Malabsorption conditions Planning Enteral Nasal tubes or enterostomies Investigate cost & availability Planning Parenteral Sterile & aseptically prepared Cyclic best © 2007 Thomson - Wadsworth

Quality of Life Issues Economic impact Time-consuming Inconvenient Disturbed sleep Activities & work must be planned around feedings Social issues Inability to consume meals with friends & family Inability to go to restaurants & social events Fear, anxiety & depression © 2007 Thomson - Wadsworth

Ethical Issues in Nutrition Care Nutrition in Practice Ethical Issues in Nutrition Care © 2007 Thomson - Wadsworth

Ethical Principles & Health Care Patient autonomy The right to make own health care decisions Disclosure Fully informed of treatment’s risks & benefits Decision-making capacity Mental capacity to make appropriate health care decisions Treatment benefits (beneficence) should outweigh harm (maleficence) Distributive justice Would care given to one patient unfairly limit the care of other patients? © 2007 Thomson - Wadsworth

Life-Sustaining Treatments Nutrition support & hydration Cardiopulmonary resuscitation (CPR) Defibrillation Mechanical ventilation Dialysis © 2007 Thomson - Wadsworth

Legal Documents for End of Life Care Living will, medical directive Written statement specifying medical procedures desired or not desired Advanced directive Written or oral instruction regarding one’s preferences for medical treatment Durable power of attorney Another person is appointed to make health care decisions in the event of incapacitation Do-not-resuscitate (DNR) Order to withhold CPR in the event of a cardiac arrest © 2007 Thomson - Wadsworth