Parenteral Nutrition Support for Adults

PARENTERAL NUTRITION SUPPORT FOR ADULTS : 

PARENTERAL NUTRITION SUPPORT FOR ADULTS dr Iyan Darmawan Medical Director PT Otsuka Indonesia

Two primary types of PN : 

Two primary types of PN Central parenteral nutrition (CPN) and Peripheral parenteral nutrition (PPN).

Central parenteral nutrition or total parenteral nutrition (TPN) : 

Central parenteral nutrition or total parenteral nutrition (TPN) provides nutrients through a large-diameter vein, usually the superior vena cava by access of the subclavian or internal jugular vein. With CPN a hyperosmolar formula (1300 to 1800 mOsm/L) can be provided consisting of glucose (15% to 25% final concentration), amino acids, and electrolytes to fully meet the nutrient needs of the patient. Central parenteral nutrition can be maintained for prolonged periods and can be adjusted to meet nutrient and volume needs for patients who may require a fluid restriction (1). When venous access for the delivery of nutrients is required for greater than 2 weeks, CPN is indicated (2). Mirtallo JM. Introduction to parenteral nutrition. In: Gottschlich MM, ed. The Science and Practice of Nutrition Support: A Case-Based Core Curriculum. Dubuque, Ia: Kendall/Hunt Publishing Co; 2001. ASPEN Board of Directors and The Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26 (suppl)(1):1SA-138SA.

Peripheral parenteral nutrition : 

Peripheral parenteral nutrition uses the peripheral vein as venous access. This form of parenteral nutrition is similar to CPN except lower formula concentrations have to be provided due to use of the peripheral vein that can only tolerate solutions providing less than 900 mOsm/L. Compared with CPN formulas, PPN formulas have a lower dextrose concentration (5% to 10% final) and amino acid (3% final) concentrations. Because of the inability to infuse higher concentrations via the peripheral vein, larger fluid volumes often have to be administered in PPN to provide comparable energy and protein doses seen with CPN. This poses a challenge for patients requiring fluid restriction. The maximum volume of PPN usually tolerated is 3 L/day (125 mL/hour). Repletion of nutrient stores is not a goal of PPN, and it is not intended to be used in severely malnourished patients (1). PPNis indicated only for mildly to moderately malnourished patients when they are unable to ingest adequate energy orally or enterally, or when CPN is not feasible. Typically, PPN is used for short periods (up to 2 weeks) because of limited tolerance and vulnerability of peripheral veins (eg, risk of peripheral venous thrombophlebitis) (1). ASPEN Board of Directors and The Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26 (suppl)(1):1SA-138SA.

Benefits of PN : 

Benefits of PN PN nutrition has been shown to be of benefit in the following circumstances *: allogeneic bone marrow transplantation perioperative support of patients with GI cancer acute exacerbations of Crohn’s disease GI fistulas severe, acute necrotizing pancreatitis (if unable to feed   enterally at or beyond the ligament of Treitz) * Klein S, Kinney, Jeejeebhoy K, Alpers D, Hellerstein M, Murray M, Twomey P. Nutrition support in clinical practice: review of published data and recommendations for future research directions: summary of a conference sponsored by the National Institutes of Health, American Society for Parenteral and Enteral Nutrition, and American Society for Clinical Nutrition. JPEN. 1997;21:133-156.

Indications of PN : 

Indications of PN  severe malabsorption: massive bowel resection (greater than or equal to 70% resected) and severe diarrhea  intractable vomiting  moderate to severe pancreatitis  paralytic ileus  complete intestinal obstruction  enterocutaneous fistula (greater than 500 mL/day) (a trial of enteral nutrition can be considered when the output is less than 200 mL/day)  severe inflammatory bowel disease (IBD)  radiation therapy or bone marrow transplantation ASPEN Board of Directors and The Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26 (suppl)(1):1SA-138SA. Mirtallo JM. Introduction to parenteral nutrition. In: Gottschlich MM, ed. The Science and Practice of Nutrition Support: A Case-Based Core Curriculum. Dubuque, Ia: Kendall/Hunt Publishing Co; 2001. ASPEN Board of Directors. Standards of Practice for Nutrition Support Dietitian. Nutr Clin Pract. 2000;15:53-59.

Contraindications of PN : 

Contraindications of PN fully functional and accessible GI tract inability to obtain venous access whose prognosis does not warrant aggressive nutrition support whose need for PN is expected to be less than 5 days when the risks of PN exceed the potential benefit to the patient, such as severe hyperglycemia (greater than 300 mg/dL), azotemia, encephalopathy, hyperosmolality (greater than 350 mOsm/kg), and severe fluid and electrolyte disturbances ASPEN Board of Directors and The Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26 (suppl)(1):1SA-138SA. Mirtallo JM. Introduction to parenteral nutrition. In: Gottschlich MM, ed. The Science and Practice of Nutrition Support: A Case-Based Core Curriculum. Dubuque, Ia: Kendall/Hunt Publishing Co; 2001. ASPEN Board of Directors. Standards of Practice for Nutrition Support Dietitian. Nutr Clin Pract. 2000;15:53-59.

Parenteral Feeding Formulations : 

Parenteral Feeding Formulations The osmolarity of a parenteral formula depends on the energy substrate mixture, primarily dextrose, amino acid, and electrolyte content Dextrose contributes approximately 5 mOsm for each gram of dextrose, amino acids yield approximately 10 mOsm/g, and electrolytes provide approximately 1 mOsm/mEq of individual additive. For example, the estimated osmolarity of a parenteral feeding formula that provides dextrose at 150 g/L, amino acids at 50 g/L, and electrolyte additives at 150 mEq/L is 1400 mOsm/L. The maximum osmolarity tolerated by a peripheral vein is 900 mOsm/L. Formulas for peripheral vein administration usually require more fluid and higher content of fat as an energy source than those for central access, as lipids are isotonic Mirtallo JM. Introduction to parenteral nutrition. In: Gottschlich MM, ed. The Science and Practice of Nutrition Support: A Case-Based Core Curriculum. Dubuque, Ia: Kendall/Hunt Publishing Co; 2001.

Nutrient Sources and Indications : 

Nutrient Sources and Indications Carbohydrate sources: The most commonly used source of carbohydrate is dextrose. Dextrose in its monohydrate form provides 3.4 kcal/g, anhydrous form 4 kcal/g Commercial dextrose solutions are available in a wide range of concentrations ranging from 2.5% to 70%. These solutions are acidic, with a pH ranging from 3.5 to 6.5 (1,2). Formulas with final dextrose concentrations greater than 10% are reserved for central venous access. Sugar alcohol glycerol is a less frequently used carbohydrate source, providing 4.3 kcal/g. Sugar alcohol glycerol, when used in PN, has been shown to be protein sparing and to induce less insulin response than do dextrose-based solutions (3-5). More research is needed to determine the efficacy of routine use of sugar alcohol glycerol National Advisory Group on Standards of Practice Guidelines for Parenteral Nutrition. Safe practices for parenteral nutrition formulations. JPEN. 1998;22:49-66. Dickerson RN, Brown RO, White KG. Parenteral nutrition solutions. In: Rombeau JL, Caldwell MD, eds. Parenteral Nutrition. 2nd ed. Philadelphia, Pa: WB Saunders Co; 1993:310-333. Singer P, Bursztein S, Kirvela O, Mansour B, Yoshimura N, Blaustein J, Askanazi J. Hypercaloric glycerol in injured patients. Surgery. 1992;112:509-514. Lev-Ran A, Johnson M, Hwang DK, Askanazi J, Weissman C, Gersovitz M. Double-blind study of glycerol vs. glucose in parenteral nutrition of post-surgical insulin-treated diabetic patients. JPEN. 1987;11:271-274. McEvoy GK, ed. AHFS Drug Information 1999. Bethesda, Md: American Society of Health-System Pharmacists; 1999.

Carbohydrate requirements : 

Carbohydrate requirements The minimum requirements for dextrose are 1 mg/kg per minute (approximately 100 g/day for a 70-kg man). The maximum amount of carbohydrate tolerated is approximately 5 to 7 mg/kg per minute (1, 2). Hyperglycemia is the most common complication of PN and can be caused by various factors including stress (3). When carbohydrate is provided in excess, hyperglycemia, hepatic steatosis, and increased CO2 production can occur. It is recommended that serum glucose be maintained less than 200 mg/dL to prevent complications (3). For patients with hyperglycemia, PN dextrose should be started conservatively (150 to 200 g/24 hours) and gradually increased to the patients individualized goal rate. Regular insulin can be provided either subcutaneously or added directly to PN solution. When added to the solution, it is recommended that two-thirds of the total amount of sliding-scale insulin required over 24 hours be added to the next day’s PN formula (3). In some patients, a chromium deficiency could be a cause of hyperglycemia, requiring an increase in chromium in the PN formula (4). ASPEN Board of Directors and The Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26 (suppl)(1):1SA-138SA. Wolfe RR, O’Donnell TF Jr, Stone MD, Richmand DA, Burke JF. Investigation of factors determining the optimal glucose infusion rate in total parenteral nutrition. Metabolism. 1980;29:892-900. Matarese LE. Metabolic complications of parenteral nutrition therapy. In: Gottschlich MM, ed. The Science and Practice of Nutrition Support: A Case-Based Core Curriculum. Dubuque, Ia: Kendall/Hunt Publishing Co; 2001. Jeejeebhoy KN, Chu RC, Marliss EB, Greenberg GR, Robertson A. Chromium deficiency, glucose intolerance, and neuropathy reversed by chromium supplementation, in patient receiving long-term total parenteral nutrition. Am J Clin Nutr. 1977;30:531-538.

Refeeding syndrome : 

Refeeding syndrome Patients who are risk of refeeding syndrome should be monitored closely. Refeeding syndrome refers to metabolic and physiologic shifts of electrolytes and minerals (eg, phosphorus, magnesium, and potassium) that occur as a result of aggressive nutrition support (1,2). Signs and symptoms include fatigue, lethargy, muscle weakness, edema, cardiac arrhythmia, and hemolysis. Patients at greatest risk are those with marginal nutrient stores secondary to a disease or medical therapy. It is recommended that patients at risk of refeeding syndrome should start with 20 kcal/kg of formula per day and advance PN formula slowly (2). ASPEN Board of Directors and The Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26 (suppl)(1):1SA-138SA. Jeejeebhoy KN, Chu RC, Marliss EB, Greenberg GR, Robertson A. Chromium deficiency, glucose intolerance, and neuropathy reversed by chromium supplementation, in patient receiving long-term total parenteral nutrition. Am J Clin Nutr. 1977;30:531-538.

Protein sources: : 

Protein sources: Crystalline amino acids are the most common source of protein used in PN formulas providing 4 kcal/g. Standard or balanced amino acid products are mixtures of essential and nonessential amino acids ranging in concentrations from 3% to 20% (1). Most commercially available amino acid formulations may also contain various concentrations of electrolytes and/or buffers. Modified or special amino acid products have been formulated for certain disease states and conditions. (eg, renal failure, hepatic failure). The contribution of these formulas to improve overall clinical outcome is debatable. In 1993 and updated in 2002 ASPEN published guidelines for nutrition support in specific disease states (2). These guidelines serve as a basis for the following discussion of use of specialized or “designer” amino acid formulas Barber JR, Miller SJ, Sacks GS. Parenteral feeding formulations. In: Gottschlich MM, ed. The Science and Practice of Nutrition Support: A Case-Based Core Curriculum. Dubuque, Ia: Kendall/Hunt Publishing Co; 2001. ASPEN Board of Directors and The Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26 (suppl)(1):1SA-138SA.

“designer” amino acid formulas : 

“designer” amino acid formulas Formulations for liver disease: High BCAA/low aromatic amino acid solutions are designed to correct abnormal amino acid profiles associated with hepatic encephalopathy, as BCAA are metabolized independently of liver function AMINOLEBAN Formulations for metabolic stress: High branched-chain amino acids solutions have been designed for use in the septic or trauma patient or the patient with thermal injury or hypermetabolic states to support the increased muscle proteolysis associated with metabolic stress. AMIPAREN Formulations for renal disease EAA/NEAA KIDMIN Pediatric formulations: Special pediatric formulas have been designed to meet the unique amino acid requirements of neonates, infants, and children to promote better weight gain, nitrogen balance, and growth and to avoid an excess of certain amino acids (eg, phenylalanine, methonine)). Such products generally contain taurine, tyrosine, histidine, arginine, and L-cysteine (semi-essential to neonates) Glutamine is considered a conditionally essential amino acid during times of metabolic stress. Considerable interest has been targeted on the potential effects of glutamine

Protein requirements: : 

Protein requirements: Protein requirements are based on the patient’s individual needs and disease process. Provision of approximately 700 kcal of nonprotein energy (specifically carbohydrate) achieves the maximum protein sparing possible without adding protein to the diet (1). Nitrogen equilibrium will not be achieved until both protein and total energy intake is adequate. It is difficult to determine the exact nonprotein calorie-to-nitrogen ratios for protein repletion in stressed patients; however, it is generally recommended to provide 80 to 150 kcal for every gram of nitrogen (2). Calloway DH, Spector N. Nitrogen balance as related calorie and protein intake in young men. Am J Clin Nutr. 1959;2:405-412. Barton RG. Nutrition support in critical illness. Nutr Clin Pract. 1994;9:127-139.

Lipid sources : 

Lipid sources Isotonic lipid emulsions are used to provide energy and essential fatty acids. Lipid sources are derived from either soybean oil or as a combination of soybean and safflower oils. Lipid sources are emulsified with egg yolk phospholipid; therefore, use may be contraindicated in patients with known egg allergies. Each gram of lipid provides 9 kcal. Lipid emulsions are available in 10% (1.1 kcal/mL), 20% (2 kcal/mL), and 30% (3 kcal/mL) concentrations. Of these, the 30% lipid formulation is approved only for compounding of total nutrient admixture, not for direct IV administration * *Barber JR, Miller SJ, Sacks GS. Parenteral feeding formulations. In: Gottschlich MM, ed. The Science and Practice of Nutrition Support: A Case-Based Core Curriculum. Dubuque, Ia: Kendall/Hunt Publishing Co; 2001.

Lipid requirements : 

Lipid requirements Lipids provide an important source of essential fatty acids (EFA). Two to four percent of energy needs should be supplied as linoleic acid [1-2 % of linoleic and 0.5% of alpha-linolenic](1) or 25 to 100 mg/kg EFA daily (1,3,4. A minimum of 500 mL of 10% lipid stock solution or 250 mL of 20% stock solution over 8 to 10 hours, two to three times a week, is sufficient to prevent EFA deficiency. Alternately, 500 mL of a 20% fat emulsion can be given once a week (2). Hyperlipidemia can occur with excess amounts or rapid infusion rates of IV lipids (13). Serum triglycerides levels should be evaluated before infusion of IV lipids. Acceptable serum triglycerides levels are less than 250 mg/dL 4 hours after lipid infusion for piggybacked lipids and less than 400 mg/dL for continuous lipid infusion (1). Infusion of IV lipids has been associated with impaired immune response and vascular integrity (2,3,5). Infusion of greater than 110 mg/kg per hour may result in reduced lipid clearance and impaired reticuloendothelial function and pulmonary exchange (3). It is recommended that fat intake should be restricted to less than 30% of total energy, or 1 g/kg/day, and provided slowly over 8 to 10 hours if administered as an IV supplement (3). Current guidelines recommend no greater than 2.5 g/kg/24 hour be provided to adult patients (1). Carnitine deficiency can lead to fat deposition in the liver and muscle, impaired ketogenesis, and neurologic symptoms. Parenteral nutrition solutions do not contain carnitine, and supplemental use in adults has not been studied. However, carnitine supplementation has been suggested for neonates receiving PN for more than 2 weeks (6). ASPEN Board of Directors and The Clinical Guidelines Task Force. Guidelines for the use of parenteral and enteral nutrition in adult and pediatric patients. JPEN. 2002;26 (suppl)(1):1SA-138SA. Matarese LE. Metabolic complications of parenteral nutrition therapy. In: Gottschlich MM, ed. The Science and Practice of Nutrition Support: A Case-Based Core Curriculum. Dubuque, Ia: Kendall/Hunt Publishing Co; 2001. Seidner DL, Mascioli EA, Istfan NW, Porter KA, Selleck K, Blackburn GL, Bristrian BR. Effects of long-chain triglyceride emulsions on reticuloendothelial system function in humans. JPEN. 1989;13:614-619. Holman RT. The ration of trienoic:tetraenoic acids in tissue lipids as a measure of essential fatty acid requirement. J Nutr. 1960;70:410-415. Kollef MN, McCormack MT, Caras WE, Reddy VV, Bacon D. The fat overload syndrome: successful treatment with plasma exchange. Ann Intern Med. 1990;112:545-546. Tibboel D, Delemarre FM, Przyrembel H, Bos AP, Affourtit MJ, Molenaar JC. Carnitine deficiency in surgical neonates receiving total parenteral nutrition. J Pediatr Surg. 1990;25:418-425.

Hypocaloric Feeding : 

Hypocaloric Feeding 10–20 kcal/kg of ideal or adjusted weight and 1.5–2 g/kg ideal weight of protein may be beneficial during the acute stress response During the stress response, hepatic glucose production is doubled and provision of glucose at a rate of 4 mg/kg/min is only able to suppress glucoseproduction by 50%, which in nonstressed individuals would nearly abolish endogenous glucose production. Megan Boitano. Hypocaloric Feeding of the Critically Ill.Nutrition in Clinical Practice 21:617–622, December 2006