Adult Enteral NutritionDeciphering the Code

Mark H. DeLegge, MD, FACG, AGAF, FASGE

Digestive Disease CenterCharleston, SC

Indications for EN

• “If the gut works…use it”

• EN is the preferred route of nutrition when oral intake is inadequate or a patient is unable to eat.

What Do We Infuse?

Formula Selection

• Assess digestive and absorptive capacity and GI tolerance

• Determine kcal, protein, fluid, vitamin and mineral requirements

• Determine if there are any mineral or electrolyte restrictions

• Assess indication for specialty formula

• Identify tube of type and infusion method

What’s the Situation• 65 y/o F s/p CVA• NG tube for feeding• Weight: 60 kg• Est kcal needs: 1500kcal/day (25 kcal/kg/day)• Est protein needs: 60 gram/d (1 gm/kg)• Normal gastrointestinal function• No mineral or electrolyte restrictions

– Renal disease

Tube Feeding Formulas

• *Blenderized (Table food)

• Standard isotonic (Most common)

• HN - High nitrogen

• Nutrient dense

• Fiber-containing

• Hydrolyzed

• Specialty

Formula Cal/cc Protein/L

(gm)

Free H20/L

Standard 1.06 44 842

Calorie Dense

2.0 84 700

High Nitrogen

1.3 67 837

Small Peptide

1.0 40 - 75 850

Immune Enhancing

1.5 94 759

Hydrolyzed 1.0 42 867

In Our Patient

• Normal GI function

• No need for high protein diet

• No evidence of renal failure, uncontrolled diabetes

• No requirement of “high-tech” specialty formula

• 1500 kcal/24 hours = 60 cc/hr

Blenderized Product

• Essentially blenderized table food

• 1 calorie/cc

• 85.4% water

• Osmolality: 340 mosmo

• Lactose-free

• Moderately expensive Compleat-B

Standard Enteral Products

Low residue 1 cal/cc 300 mOsmo Lactose-free Inexpensive, moderately palatable Casein protein - biological value lower

than other sources of protein

Nutrient Dense Formulas

Low residue Functional GI tract required Lactose-free Inexpensive, moderately palatable Casein protein Fluid restricted patients Renal compromised patients Nutren 2.0, Magnacal, Jevity 1.5

High Nitrogen Products

Low residue Functional GI tract required Lactose-free Inexpensive, moderately palatable Casein protein, higher concentration Patients with wound healing, post-surgical,

trauma, sepsis Example: Replete, Osmolite HN

Peptide-Based Formulas

Protein source: short peptides +/- free AAs In times of stress small bowel mucosa

ability to absorb short peptides increases Altered GI tract absorption

Critical care Inflammatory bowel disease

More expensive than standards Example; Peptamen, Perative

Dipeptides, Tripeptides, Short Peptides

• Small intestine absorption (PepT1)

• Fasting: increase in small intestine (PepT1) and (PepT1MRNA) at the small bowel mucosa (peptides 6-100 in length)

• Inflammatory gut conditions – increase in small intestine (PepT1) production

• Ogihara et al; Histochem J, 1999

Elemental Formulas

Macronutrients in most elemental form Protein: Free AAs Fat: MCT, long-chain fats CHO: glucose polymers Expensive, unpalatable, High osmolality Example: Crucial, Vital HN, Vivonex

Our Patient

• 1500 kcal, 60 gm protein, 1800 cc H20

• Standard:– 1.5 liters (1500 kcal)– 66 gm protein

– 1270 cc/H20

• Nutrient dense (2 cal/ cc)– 750 cc– 63 gm protein

– 462 cc H20

Specialty Additives

Immune Enhancing Formula

• Definition• L-Arginine• Glutamine• Dietary Nucleotides• N-3 Fatty Acids

Immune Modulating Ingredients

Immune Modulating Nutrition: Meta-Analysis

Author Journal # of Pts Studies Outcome

Heys Ann Surg 1999

1009 11 Dec infection

Beale CCM 1999 1482 12 Dec infection

Dec vent

Heyland JAMA 2001 2419 22 Dec infection

Dec LOS

Waitzberg WJS 2006

(in press)

2305 17 Dec infection

Dec LOS

Consensus RecommendationsAppropriate Patient Populations

• Patients undergoing elective GI surgery: Greatest benefit in malnourished

• Trauma patients with ISS 18 or ATI 20• Needs further study

• Patients with severe sepsis

• Other patients that may benefit:– Ventilator dependent– Elective surgery (prolonged need for ventilator, cancer with

malnutrition)– Severe head injury– Burns 30% (third degree)– Head and neck cancer

Metabolic Effects of Lipids

• Omega-3 series– Vasodilatory– Anti-inflammatory– Anti-aggregatory– Immunostimulant– Anti-arrhythmic

• Omega-6 series– Vasoconstrictive– Pro-inflammatory– Pro-aggregatory– Immunosuppressive– Pro-arrhythmic

Enteral FormulationsMedium Chain Triglycerides

• Easier absorption

• Less pancreatic stimulation

• Less immune suppressing

Medium Chain Triglycerides

• 24 HIV + patients with malabsorptive disease

• LCT vs MCT enriched oral formulas

• 3 day 100 gm fat diet, then trial diet 3 days

• Craig et al; JADA, 1997

0

100

200

300

Baseline MCT

StoolOutput

Stool FatGm/Day

LCT

Types of Feeding Administration

• Continuous- given over 24 hours

• Bolus - syringe feedings given every few hours (e.g. 240cc every 4 hours)

• Nocturnal - TF given over 8-12 hours at night while patient is sleeping

ConclusionKnow the code

• Assess GI tolerance• Determine calorie,

water, protein needs• Evaluate co-morbidities• Determine any special

needs• Determine infusion

method• Write the nutrition

prescription