Nutrition Support for ICU Patients Enteral and Parentral Nutrition A. Afaghi, MPH, PhD Qazvin University of Medical Science, School of Medicine

Nutrition support Nutrition support is the delivery of formulated enteral or parenteral nutrients for the purpose of maintaining or restoring nutritional status. Enteral nutrition (EN) refers to the provision of nutrients into the gastrointestinal tract (GIT) through a tube or catheter. In certain instances EN may include the use of formulas as oral supplements or meal replacements. Parenteral nutrition (PN) is the provision of nutrients intravenously.

Enteral and Parenteral Nutrients PN should be used in patients who are or will become malnourished and who do not have sufficient gastrointestinal function EN decreases the incidence of hyperglycemia when compared with PN.

ENTERAL NUTRITION By definition, enteral implies using the GIT, primarily via "tube feeding." When a patient has been determined to be a candidate for EN, the location of nutrient administration and type of enteral access device is selected.

ENTERAL NUTRITION Nasoenteric Routes and tube placement Nasogastric (Cervical pharyngostomy or esophagostomy, Gastrostomy) Nasoduodenal (Gastrostomy) Nasojejunal (Jejunostomy) (duodenum, jejunum, ileum are 3 sections of small intestine)

Nasogastric tubes (NGTs) are the most common way to access the GIT. They are generally appropriate only for those requiring short-term EN, which is defined as 3 or 4 weeks. Typically, the tube is inserted at the bedside by a nurse or dietitian. The tube is passed through the nose into the stomach. Patients with normal gastrointestinal function tolerate this method, which takes advantage of normal digestive, hormonal, and bactericidal processes in the stomach. Rarely, complications can occur

Factors to Consider When Choosing an Enteral Formula Ability of the formula to meet the patient's nutritional requirements Caloric and protein density of the formula (i.e., kcal/mL, g protein/mL, kcal :nitrogen ratio) Gastrointestinal function of the patient Presence of lactose, which may not be tolerated Sodium, potassium, magnesium, and phosphorus content of the formula, especially in cardiopulmonary, renal, or hepatic failure Type of protein, fat, carbohydrate, and fiber in the formula tolerable for the patient's digestive and absorptive capacity Viscosity of the formula related to tube size and method of feeding

Monitoring the Patient Receiving Enteral Nutrition Abdominal distention and discomfort Fluid intake and output (daily ) Gastric residuals (every 4 hr) if appropriate Signs and symptoms of edema or dehydration (daily) Stool output and consistency (daily) Weight (at least 3 times/wk) Nutritional intake adequacy (at least 2 times/wk) Serum electrolytes, blood urea nitrogen, creatinine, (2-3 times/wk) Serum glucose, calcium, magnesium, phosphorus,(weekly or as ordered)

Macronutrients, vitamins, minerals, fluids 30% to 85% of Energy as CHO 15% and 30% of the total kilocalories of standard formulas are provided by lipids 15% Energy as protein

MCT (Medium chain triglyceride) MCTs can be added to enteral formulas because they do not require bile salts or pancreatic lipase for digestion and are absorbed directly into the portal circulation. Most formulas provide 0% to 85% of fat as MCTs. MCTs do not provide the essential linoleic or linolenic acids; they must therefore be provided in combination with long-chain triglycerides. MCT is available naturally in milk and coconut oil

Omega-3 Formulas contain a combination of (omega-3 fatty acids and (omega-6 fatty acids. The (omega-3 fatty acids include eicosapentaenoic acid and docosahexanoic acid. These are considered advantageous compared with (omega-6 fatty acids because of their anti inflammatory effect

Vitamins, Minerals, and Electrolytes Most, but not all available formulas are designed to meet the dietary reference intakes (DRls) for vitamins and minerals if a sufficient volume is taken.

Fluid Fluid needs for adults can be estimated at 1 mL of water per kilocalorie consumed, or 30 to 35 mL/kg of usual body weight Without an additional source of fluid, tube- fed patients may not get enough free water to meet their needs, particularly when concentrated formulas are used. Standard (1 kcallmL) formulas contain approximately 85% water by volume, but concentrated (2 kcallmL) formulas contain only approximately 70% water by volume. All sources of fluid being given to a patient receiving EN, including feeding tube flushes, medications, and intravenous fluids, should be considered when determining and calculating a patient's intake. Additional water can be provided through the feeding tube as needed

Energy, protein requirements Metabolic basal:1 kcal/kg/h (for men), 0.9 kcal/kg/h (for women) Extra energy is required for activity ( kcal) Protein 0.8 g/kg/B/weight

Traditional & formulated foods Whole Milk or yogurt, 240 ml=150 kcal,12g CHO,8g protein Fresh Fruit juice (apple), 240 ml= 120 kcal Filtered Soup, 240 = 100 kcal Canned fruit, 240 = 150 kcal Coconut oil, 1 g = 9 kcal, MCT Ensure (gluten free, lactose free), 400 g Can = 1724 kcal, 62 g protein, 64 g fat 100 g = 431 kcal, 15.5 g protein, 14 g fat 54.5 g (6 spoon+190ml=230ml) =230 kcal, 1 ml=1 kcal 400 g (1 Can) = 7 and half meals of 230 ml

Enteral Feeding: (a) Patient’s Needs (Adults) Energy: Kcal/BW.d -1 Amino acids: Maintenance: g/Kg BW. d -1 Catabolic phase: g/Kg BW. d -1 Ca: mg/d Zn: mg/d Vitamin C: 100 mg/d

Enteral Feeding: (b) Some Common Dietary Orders Clear liquid 150 mL/3hr High energy liquid 300 mL/3hr High protein liquid mL/3hr … Total amount of liquid intake via EF: mL/d

Enteral Feeding: (c) Some data on selected commercial liquids (USDA Food Composition Table) Chicken noodle composition/100 g (amount in mL) Energy: 25 Kcal ( Kcal) Protein: 1.27 g ( g) Ca: 6 mg ( mg) Zn: 0.16 mg ( mg) Vitamin C: 0

Enteral Feeding: (c) Some data on selected commercial liquids (USDA Food Composition Table) Beef noodle composition/100 g (amount in mL) Energy: 34 Kcal ( Kcal) Protein: 1.93 g ( g) Ca: 8 mg ( mg) Zn: 0.62 mg ( mg) Vitamin C: 0.2 mg ( mg)

Enteral Feeding: (c) Some data on selected commercial liquids (USDA Food Composition Table) Cream of chicken composition/100 g (amount in mL) Energy: 77 Kcal ( Kcal) Protein: 3.01 g ( g) Ca: 73 mg ( mg) Zn: 0.27 mg ( mg) Vitamin C: 0.5 mg (6-12 mg)

Artificial Nutrition: A Two-Edged Sword Inability of hypercaloric feeding to increase lean body mass, especially skeletal muscle mass, has been repeatedly shown. Kotler DP. Ann Intern Med 2000;133:

DO NOT OVER-FEED THE PATIENT!

The outcome of indequate intake: Malnutrition (Cachexia)

Cachexia: “kakos”= bad and “hexis”=condition Eighty percent of patients with upper GI cancers have already experienced substantial weight loss on diagnosis Bruera E. Br Med J 1997;315:

Body weight changes in healthy adults ±2% in one month ±3.5% in three months ±5% within 6 months Kotler DP. Ann Intern Med 2000;133: Rosenbaum K et al. JPEN 2000;24:52-5. Weight loss of ≥10% a starting criterion for the anorexia-cachexia syndrome in obese patients Inui A. CA Cancer J Clin 2002;52:72-91.