1. CHOOSING AN ENTERAL FEEDING FORMULA
Michele Port, P.Dt.
Clinical Dietitian
March 2014

2. LEARNING OBJECTIVES
Identify common sources of protein, carbohydrate and fat used in enteral feeding formulas.
Identity formulas which could benefit your patient population and to include in your formulary.
Become familiar with high protein formulas and modular products.

3. OUTLINE Introduction Choice of an enteral formula Formula composition
Types of feedings
Enteral formulary
Case study
Conclusion

4. INTRODUCTION Choice of an enteral formula depends on several factors.
You need to complete your nutrition assessment and calculate your
patient’s nutritional requirements before deciding on an appropriate
formula. Formulas from different companies are often similar.
The decision of which formulas to include in a formulary comes down
to your patient population with their specific needs and cost.

5. CHOICE of an ENTERAL FORMULA
Depends on:
Nutritional requirements: calories, protein, other
GI symptoms? Ex.: GERD, gastroparesis,  bowel motility.
Digestion and absorption intact? Does the patient have history of IBD, high ileostomy output, bowel resections ?
Organ dysfunction or specific disease state Ex.: renal failure on dialysis.
Fluid restriction.
Viscosity of formula.
Cost.
Format: Closed versus Open system.

6. CHOICE of an ENTERAL FORMULA
Many formulas similar in composition.
Different companies may produce similar products
Usually slight differences in macro or micronutrients
Best way to compare products is in a chart format
Speciality products: need to assess literature to verify claims
Choice of formulas will depend on your patient population Ex.: Hospitals with dialysis program should have a renal formula.

7. FORMULA COMPOSITION Adult formulas are complete nutrition.
Contain micro and macronutrients based on dietary reference intake (DRI) of the Institute of Medicine.
Majority are lactose-free.
Formulas are classified as:
Polymeric:
Intact nutrients
Appropriate for normal gut function
Elemental / Semi-Elemental also referred to as predigested:
Protein, carbohydrate predigested or semi-digested
Use if compromised GI function
There are also modular products which provide only carbohydrate, protein, or fat to increase the macronutrient as required.

8. SOURCE of CARBOHYDRATE
FORMULA COMPOSITION
CARBOHYDRATE
Primary energy source in most enteral formulas.
Usually 40%-90% of total calories
SOURCE of CARBOHYDRATE
Polymeric
Elemental / Semi-Elemental
Corn Syrup Solids
Corn Starch
Hydrolyzed Corn Starch
Maltodextrin
Sucrose
Fructose

9. FORMULA COMPOSITION PROTEIN Source of nitrogen and energy
In enteral formulas:
Polymeric intact protein: Whole protein or protein isolates (casein, soy), lactalbumin, egg albumin and whey
Elemental / Semi-Elemental: Hydrolyzed protein, di- and tri- peptides, amino acids

10. FORMULA COMPOSITION FAT Concentrated source of energy
Source of essential fatty acids (linoleic and linolenic acid)
Medium chain triglycerides (MCT) do not contain essential fatty acids
FAT SOURCE
Polymeric
Elemental / Semi-Elemental
Safflower Oil
Fish Oil
Coconut Oil
Soybean Oil
Sardine Oil
Palm Kernel Oil
Canola Oil
Menhaden Oil
Corn Oil
Borage Oil
Soy Lecithin
Structured Lipids

11. FORMULA COMPOSITION FAT
MCT: Absorbed in portal circulation does not require chylomicron formation and bile salts for digestion and absorption.
Structured Lipid: Mixture of MCFA and LCFA on same glycerol molecule.
Omega-3 fatty acids (fish oils) metabolized to prostaglandins of series and leukotrienes of the 5 series (anti-inflammatory properties).

12. FORMULA COMPOSITION VITAMINS AND TRACE ELEMENTS:
Usually adequate for majority of patients if they are receiving 100% of calorie requirements.
Need to check to ensure adequate calcium and vitamin D content, DRI for Vitamin D has increased in past few years.
High GI output: feeds may need to be supplemented with Zn and Se.
For patients not receiving 100% of nutrition requirements add multivitamin and mineral supplement.
Patients with pressure ulcers may need to be supplemented with multivitamins and minerals, vitamin C and Zn.

13. FORMULA COMPOSITION WATER
Usually 70%-80% of formula
Need to include water in formula in total fluid intake
OSMOLALITY (concentration of solute particles in a solution)
Should not be included in the decision to use a formula It has little to do with formula tolerance.
ELECTROLYTES
Most formulas contain adequate amounts
Hepatic formula very low in sodium

14. TYPES OF FORMULAS POLYMERIC Standard (Ex.: Osmolite 1 CAL) 29%
Need good digestion and absorption
High Protein (Ex.: Isosource VHN, Isosource VHP, Promote) 20%-25% Protein
Carbohydrate
54%
Protein
17%
Fat
29%
Isosource VHN
Isosource VHP
Promote
Carbohydrate
50%
45%
52%
Protein
25%
Fat
30%
23%

15. TYPES OF FORMULAS POLYMERIC
High Protein (Ex.: Isosource VHN, Isosource VHP, Promote) %-25% Protein
Indications:
 Catabolism
Wound healing
Pressure ulcers
Patients on propofol
Plasmapheresis
CVVHD - continuous dialysis
Burn patients

16. TYPES OF FORMULAS POLYMERIC
Energy Dense: (Ex.: Nutren 1.5, Nutren 2.0, Resource 2.0, Two Cal HN)
Provide Kcal / mL
Indications:
Fluid restriction
CHF
Renal failure
Ascites
Hyponatremic (hypervolemic)
Commercial blenderized food product (Ex.: Compleat) made from pureed foods (chicken, fruit vegetable, juice, etc…)
Formula is very well tolerated but very viscous

17. FORMULA COMPOSITION POLYMERIC Fibre
Fibre-containing formula (Ex.: Jevity, Jevity 1.5, Isosource 1.5, Isosource VHN, Isosource HN Fibre) combination of soluble and insoluble fibre:
Promoted to maintain bowel regularity:
Prevent constipation in long term EN
Decrease diarrhea in short term EN
Combination of soluble and insoluble fibre:
Soluble fibre: Fermented to SCFA in colon by bacteria, promotes sodium and water absorption
Insoluble fibre: Increases fecal weight / bulk

18. FORMULA COMPOSITION POLYMERIC Fibre
Need adequate amounts of fluid to prevent constipation and impaction / obstruction
Avoid fibre in hypotensive patients - high risk for developing ischemic bowel
McClave et al. JPEN 2009; 33:27
Chen et al. NCP 2009; 24: 344

19. FORMULA COMPOSITION POLYMERIC Prebiotics Prebiotics are:
Resistant to gastric acidity and digestion
Fermented by GIT endogenous microbiome
Stimulate growth of intestinal microbiota which contains health benefits
Examples:
Inulin (chicory, leeks, onions, garlic)
Inulin type fructans (oligo fructose or fructo oligo saccharides)
Lactulose

20. FORMULA COMPOSITION POLYMERIC Prebiotics
FOS added to some enteral formulas suh as Jevity 1.2, Jevity 1.5, Nepro with carb steady, Two Cal HN, Peptamen AF, Peptamen
Fermented by bacteria in colon to SCFAs which stimulate growth of beneficial bacteria in colon and stimulate water and electrolyte absorption

21. FORMULA COMPOSITION ELEMENTAL / SEMI-ELEMENTAL
Designed to improve nutrient absorption in maldigestive or malabsorptive states such as pancreatic insufficiency.
Ex.: Elemental: VitaL HN, Vivonex Plus Semi-Elemental: Peptamen, Peptamen 1.5, Peptamen AF
If high protein intake is required, Peptamen AF provides g protein / 1200 Kcal.

22. FORMULA COMPOSITION DISEASE SPECIFIC RENAL
Dialysis Patients (Intermittent Hemodialysis) Ex.: Nepro, NovaSource Renal
Energy dense: 2 Kcal / ml
Low in K+ and phosphorus
Protein content increased to 18% by manufacturers so it can be used for AKI
Nepro with Carb Steady: 81g protein / litre
Novasource Renal: 91g protein / litre
High fat (majority of fat long chain FA) with concern in patients with gastroparesis and pancreatic insufficiency

23. FORMULA COMPOSITION DISEASE SPECIFIC RENAL
Predialysis patients. Ex.: Suplena
Calorie dense 2 Kcal / mL
Low protein: 30g protein / litre
Low K and phosphorus
High fat: 96g / litre

24. FORMULA COMPOSITION DISEASE SPECIFIC HEPATIC Ex.: NutriHep
Energy dense: 1.5 Kcal / mL
Increased branch-chained amino acids
Decreased aromatic amino acids
Semi-elemental:
Protein: Free amino acids and whey
Carbohydrate: Maltodextrin and corn starch
Fat: MCT: LCT ratio is 70%: 30%
With current evidence, routine use not warranted in hepatic encephalopathy
Very expensive

25. FORMULA COMPOSITION DISEASE SPECIFIC
DIABETIC Ex.: Glucerna, Resource Diabetic
Low Carbohydrate 34%-36%
17%-20% protein
High fat (> 40%)
Contains fibre
May not be well tolerated with diabetic gastroparesis
Indication:
Hyperglycemia, patients on corticosteroids
Optimize glycemia with insulin protocol prior to using this product

26. FORMULA COMPOSITION DISEASE SPECIFIC
PULMONARY Ex.: Oxepa, for ALI and ARDS
High in fat: 55% (contains fish oil)
 Omega-3 to Omega-6 ratio
Supplemented with antioxidants (Vit E, Vit C and beta-carotene)

27. FORMULA COMPOSITION DISEASE SPECIFIC
IMMUNE-ENHANCING FORMULA Ex.: Impact, Peptamen AF, Oxepa
Formulas contain one or more of the following: glutamine, arginine, Omega-3 FA, nucleotides and antioxidants.
Oxepa and Peptamen AF are very high in Vitamin A content, need to take this into consideration if tube feeding a pregnant woman.
In critically-ill, arginine and glutamine should not be supplemented

28. MODULAR PRODUCTS PROTEIN Ex.: Beneprotein powder Whey protein
6g protein / scoop 7 g
Provides 25 Kcal / scoop
Relatively low in K, phos but must be considered if using a large number of scoops
Mixes easily with water
Useful to supplement formulas when protein requirement is 2g / kg
Liquid protein supplements exist but are not availbale in Canada

29. MODULAR PRODUCTS CARBOHYDRATE Ex.: Polycose FAT Ex.: MCT Oil
Glucose powder mixed with water or beverages to increase calories
FAT Ex.: MCT Oil
Used to increase calories in patients with poor fat digestion or malabsorption
120 Kcal / tbsp

32. Case Study
56 yo male Lt. vertebral artery dissection and basilar artery thrombosis after neck manipulation by a chiropractor in Tracheostomy and PEG placed in 2010 and pt was transferred to a long term care hospital.
July 2011: Admitted to ICU with Hypoxemic respiratory failure (pneumonia), coccyx pressure ulcers - infected. Labs unremarkable, low albumin as expected.
On Peptamen 1.5 enteral feeding via PEG due to intolerance of other formulas especially one with fibre prior to admission.
Diarrhea likely due to antibodics. No C. difficile.
Pectin added as soluble fibre source
Adequate amounts of Vitamin C, Zn, Vitamin A for wound healing
Adequate calcium and Vitamin D
Calories: calculated with Penn state equation
Protein: 1.5g / kg

33. Case Study
Diarrhea resolved, pressure ulcers started healing, weaned from ventilator. Transferred to medical ward November 2011.
July 2012: returned to ICU with respiratory failure, hypersalivation, blackspots in PEG.

34. What were the black spots?
Case Study
What were the black spots?

35. Case Study Black spots likely fungus.
August 1: PEG tube changed – contrast used and X-ray done to ensure no leak.
Peptamen 1.5 feeds restarted.

36. Case Study Aspiration? Green secretions around tracheostomy
No BM August 3-7
Enema given
Regurgitation of feeds August 18
Abdo X-ray shows contrast (from August 1) throughout bowel

37. Case Study Recommend PEG/J
Pt’s wife refused, she wants him fed into stomach
Promotility drug started
Golitely used via PEG with L/A stool

38. Case Study
Changed formula to Isosource 1.5 with 7g fibre / litre (soy fibre and guargum)
Changed feeds to intermittent due to high residuals (400ml)

39. Case Study Constipation despite laxatives and promotility drugs
Trial of various laxatives – none worked
BM every 4 days with laxative
Bloating
Algorithm for constipation in neurological disease was followed

40. Case Study Gastroenterologist consulted
Recommended high fibre high fat diabetic formula (12g soy fibre / litre, 40% calories as fat)
Wife believes pt had candida in stomach and is bloated for this reason
Ongoing bloating
Dry hard stool. Water provided was increased.
Ongoing bloating with diabetic formula but BM q 2-3 days with laxatives and stool softener

41. Case Study Spoke with wife re. pureed food formula Agrees to trial
5.7g fibre / litre (vegetable fibre and hydrolyzed guargum)
Protein powder (8 scoops daily) to provide enough protein
Intermittent feedings: 3 times per day
Soft / pasty BM 1-2 times per day
No laxatives or stool softener used
Prune juice given one time per day via tube
Continue with adequate water

42. Case Study
Patient, wife, healthcare team happy with latest change of formula

43. References
Abbott Nutrition. Adult Nutritional products Guide. Dec
Boullata J, Nieman Carney L, Guenter P, eds. Enteral formula selection and preparation In: A.S.P.E.N. Enteral Nutrition Handbook, Silver Spring, MD: American Society for Parenteral and Enteral Nutriiton; 2010:
Chen Y, Peterson SJ. Enteral feeding formulas: which formula is right for your adult patient? Nutr Clin Pract ; 24:
DeChicco RS, Materese LE. Determining the nutrition support regimen. In: Matarese L, Gottschlich M, eds. Comtemporary Nutrition Support Practice. Philadelphia, Pennsylvania: WB. Saunders Co., 1998;
Lefton J, Halasa Esper D, Kochevar M. Enteral formulations. In: Gottschlich Met al., eds The A.S.P.E.N. Nutrition Support Care Curriculum. Silver Spring, MD; American Society for Parenteral and Enteral Nutrition; 2007:
Nestlé Health Science. Healthcare Nutrition Product Guide Sept 2013.
Winge K, Rasmussen D, Werdelin LM. Constipation in neurologiocal disease J Neurol Neurosurg Psychiatry 2003; 74:

44. THANK YOU