Enteral Nutrition forAdults: Administration Issuesincluding material from

Dietitians in Nutrition Support

A DIETETIC PRACTICE GROUP OFAMERICAN DIETETIC ASSOCIATION“Your link to nutrition and health.”

Contraindications for EN Severe acute pancreatitis High output proximal fistula Inability to gain access Intractable vomiting or diarrhea Aggressive therapy not warranted Expected need less than 5-7 days if

malnourished or 7-9 days if normally nourished

ASPEN. The science and practice of nutrition support. A case-based core curriculum. 2001; 143

Contraindications for EN Inadequate resuscitation or

hypotension; hemodynamic instability

Ileus Intestinal obstruction Severe G.I. Bleed

Indicators of Adequate Fluid Resuscitation in Critically Ill Pts Urine output should be >30 ml/hour Heart rate <120 beats/minute; preferably

<100 beats/minute Systolic BP should be ~100 Ask staff/medical team If patient is receiving fluid boluses in

addition to continuous IVF, likely they are not adequately resuscitated

Nasogastric Tubes

Nasogastric Tubes

Definition A tube inserted through the nasal passage

into the stomachIndications: Short term feedings required Intact gag reflex Gastric function not compromised Low risk for aspiration

French Units—Tube Size Diameter of feeding tube is measured in

French units 1F = 33 mm diameter Feeding tube sizes differ for formula types and

administration techniques Generally smaller tubes are more comfortable

and better suited to NG or NJ feedings May be more likely to clog with viscous

formula or formula mixtures

Nasogastric Tubes

Advantages: Ease of tube placement Surgery not required Easy to check gastric residuals Accommodates various administration techniques

Nasogastric Tubes

Disadvantages: Increases risk of aspiration (maybe) Not suitable for patients with compromised gastric

function May promote nasal necrosis and esophagitis Impacts patient quality of life

Nasoduodenal/Jejunal

Definition A tube inserted through the nasal passage through

the stomach into the duodenum or jejunum

Indications: High risk of aspiration Gastric function compromised

Nasoduodenal/Jejunal

Advantages: Allows for initiation of early enteral feeding May decrease risk of aspiration Surgery not required

EAL EN Tube Placement Guidelines Critical Care Enteral Nutrition (EN) administered into the

stomach is acceptable for most critically ill patients.

If your institution's policy is to measure GRV, then consider small bowel tube feeding placement in patients who have more than 250ml GRV or formula reflux in two consecutive measures.

Small bowel tube placement is associated with reduced GRV.

ADA EAL Critical Care Guidelines accessed 8-07

EAL EN Guidelines (Critical Care)

Adequately-powered studies have not been conducted to evaluate the impact of GRV on aspiration pneumonia.

There may be specific disease states or conditions that may warrant small bowel tube placement (e.g., fistulas, pancreatitis, gastroporesis), however they were not evaluated at this phase of the analysis. Fair; conditional

ADA EAL Guidelines Critical Care accessed 8-07

Nasoduodenal/Jejunal

Disadvantages: Transpyloric tube placement may be difficult Limited to continuous infusion May promote nasal necrosis and esophagitis Impacts patient quality of life

Orogastric Tube is placed through mouth and into

stomach Often used in premature and small infants

as they are nasal breathers Not tolerated by alert patients; tubes may be

damaged by teeth

Gastrostomy-Jejunosotomy

Enterostomy Placement

Gastrostomy Jejunostomy

Gastrostomy

Definition A feeding tube that passes into the stomach

through the abdominal wall. May be placed surgically or endoscopically

Indications: Long-term support planned Gastric function not compromised Intact gag reflex present

Gastrostomy

Disadvantages: May require surgery Stoma care required Potential problems for leakage or tube

dislodgment

Gastrostomy

Jejunostomy

Definition A feeding tube that passes into the jejunum

through the abdominal wall. May be placed endoscopically or surgically

Indications: Long-term feeding option for patients at high risk

for aspiration or with compromised gastric function

Jejunostomy

Advantages: Post-op feedings may be initiated immediately Decreased risk of aspiration Suitable option for patients with compromised

gastric function Stable patients can tolerate intermittent feedings

Jejunostomy

Disadvantages: Requires stoma care Potential problems related to leakage or tube

dislodgement/clogging may arise May restrict ambulation Bolus feedings inappropriate (stable patients may

tolerate intermittent feedings)

Determining Method of Administration Feeding site Clinical status of patient Type of formula used Availability of pump Mobility of patient

Initiation of Enteral Feedings Dilution of enteral formulas not generally

recommended Initiate at full strength at slow rate and

steadily advance Allows achievement of goal rates more

quickly; less manipulation of formula

Administration Bolus Intermittent Continuous Cyclic

Bolus Feedings

Definition Infusion of up to 500 ml of enteral formula into

the stomach over 5 to 20 minutes, usually by gravity or with a large-bore syringe

Indications: Recommended for gastric feedings Requires intact gag reflex Normal gastric function

Bolus Feedings

Advantages: More physiologic Enteral pump not required Inexpensive and easy administration Limits feeding time so patient is free to ambulate,

participate in rehabilitation, or live a more normal life in the home

Makes it more likely patient will receive full amount of formula

BolusFeeding

Bolus Feeding

Disadvantages: Increases risk for aspiration Hypertonic, high fat, or high fiber formulas may

delay gastric emptying or result in osmotic diarrhea

Initiation of Bolus Feedings Adults: Initiate with full strength formula 3-

8 times per day with increases of 60-120 ml q 8-12 hours as tolerated up to goal volume; does not require dilution unless necessary to meet fluid requirements

Children: Initiate with 25% of goal volume divided into the desired number of daily feedings; increase by 25% each day divided among all feedings until goal volume is reached

ASPEN Nutrition Support Practice Manual, 2005, 2nd ed, p. 78

Continuous Feedings

Indications: Initiation of feedings in acutely ill patients Promote tolerance Compromised gastric function Feeding into small bowel Intolerance to other feeding techniques

Continuous Feedings

Definition Enteral formula administration into the

gastrointestinal tract via pump or gravity, usually over 8 to 24 hours per day

Advantages: May improve tolerance May reduce risk of aspiration Increased time for nutrient absorption

Continuous Feedings

Disadvantages: May reduce 24-hour infusion May restrict ambulation More expensive for home support Pumps are more accurate; useful for small-bore

tubes and viscous feedings, but many payers have strict criteria for approval of pumps for home or LTC use

Initiation of Continuous Feedings Adults: Initiate at full strength at 10-40

ml/hour and advance to goal rate in increments of 10 to 20 mL/hour q 8-12 hours as tolerated

Can be used with isotonic or hyperosmolar formulas

Children: Isotonic formula full strength at 1-2 mL/kg/hour and advanced by .5-1 mL/kg/hour q 6-24 hours until goal rate is achieved

ASPEN Nutrition Support Practice Manual, 2005, 2nd ed, p. 78

Intermittent FeedingsDefinition Enteral formula administered at specified times

throughout the day; generally in smaller volume and at slower rate than a bolus feeding but in larger volume and faster rate than continuous drip feeding

Typically 200-300 ml is given over 30-60 minutes q 4-6 hours

Precede and follow with 30-ml flush of tap waterIndications: Intolerance to bolus administration Initiation of support without pump Preparation of patient for rehab services or discharge

to home or LTC facilityThe A.S.P.E.N. Nutrition Support Practice Manual, 2nd Edition, 2005

Intermittent Feedings

Advantages: May enhance quality of life

– Allows greater mobility between feedings– More physiologic– May be better tolerated than bolus

Intermittent Feedings

Disadvantages: Increased risk for aspiration Gastric distention Delayed gastric emptying

Cyclic Feedings

Definition Administration of enteral formula via continuous drip over

a defined period of 8 to 12 hours, usually nocturnally

Indications: Ensure optimal nutrient intake when:

– Transitioning from enteral support to oral nutrition (enhance appetite during the day)

– Supplement inadequate oral intake– Free patient from enteral feedings during the day

Cyclic Feedings

Advantages: Achieve nutrient goals with supplementation Facilitates transition of support to oral diet Allows daytime ambulation Encourages patient to eat normal meals and snacks

Cyclic Feedings

Disadvantages: May require high infusion rates—may promote

intolerance

Enteral Feeding Tubes

Types: pediatric vs adult; gastric vs small bowel Sizes: smaller sizes (5-8 Fr) for commercial products

delivered via pump; larger sizes for viscous, blenderized, fiber-containing formulas, gravity and bolus feedings

Weighted vs. unweighted: it was once thought that weighted tubes facilitated transpyloric passage; now dictated by personal preference

Stylet vs. no stylet: stylet facilitates tube placement beyond the pylorus for small, flexible tubes

Composition: silicone and polyurethane most comfortable

Factors Affecting Tube Selection Will the patient be fed into the stomach or

small bowel? How long will the patient need tube

feedings? Is the patient expected to resume adequate

oral feedings? Who can insert feeding tubes at my

institution?

Enteral Feeding Containers

May be rigid or flexible

Sterile or non-sterile Unbreakable,

leakproof, and disposable

Considerations in Choosing Enteral Feeding Containers Easy to fill, close and hang Easy to read calibrations and directions Appropriate size Adaptable tubing port Compatible with pump Requires minimal storage space

Adapted from ASPEN. The science and practice of nutrition support. A case-based core curriculum. 2001; 179

Closed Systems

Enteral Feeding Pumps

Factors in Pump Selection Simple to use

(intuitive) Alarm system Lightweight Long battery life Portable Volume infused

indicator

Dose function Flow rate accurate to

within 10% Approved for age

range in which it will be used

Permanently attached cord

Enteral Feeding Complications

Mechanical Gastrointestinal Metabolic Infectious

Mechanical

Feeding tube obstruction Feeding tube dislodged Nasal irritation Skin irritation/excoriation at ostomy site

Causes of Feeding Tube Obstruction Concentrated, viscous, and fiber-containing

feeding products Tube feeding contamination Checking of gastric residuals Small diameter tubes Powdered or crushed medication flushed through

tubes Acidic or alkaline medications passed through

tubes Tubes not routinely flushed after feedings are

stopped

Prevention of Feeding Tube Obstruction Flush the feeding tube, especially before

and after medication administration and bolus/intermittent feedings

Use liquid formulations of medicines where possible (but be careful of osmolarity)

Do not mix medications with enteral feedings unless shown to be compatible

Avoid crushing sustained-release or enteric-coated tablets

Treatment of Feeding Tube Obstruction Declog with irrigants (warm water) or

sodium bicarbonate/pancrealipase mixture or by mechanical means

Cola beverages, cranberry juice, and tea not recommended

The A.S.P.E.N. Nutrition Support Practice Manual, 2nd Edition, 2005

Aspiration Reported incidence of aspiration in tubefed

patients varies from .8% to 95%. Clinically significant aspiration 5% gastric-fed pts

Many aspiration events are “silent” and often involve oropharyngeal secretions

Symptoms include dyspnea, tachycardia, wheezing, rales, anxiety, agitation, cyanosis

May lead to aspiration pneumonia

Aspiration Focus has been on detection of aspiration through

use of coloring agents in enteral feedings or glucose testing of respiratory secretions

These methods have low sensitivity and questionable specificity; they do not prevent aspiration but at best detect it after it has occurred

Blue food coloring used for this purpose has been associated with morbidity/mortality in septic patients

Aspiration Prevention Keep head of bed elevated 30-45 degrees

during and 30-40 minutes after feedings Feed post-pylorically (research mixed on

this) Small, frequent feedings or continuous drip Use of promotility agents Monitoring of gastric residuals may be

helpful in identifying delayed gastric emptying and increased risk of aspiration

The A.S.P.E.N. Nutrition Support Practice Manual, 2nd Edition, 2005

Gastrointestinal Complications

Diarrhea Constipation Gastric distention/bloating Gastric residuals/delayed gastric emptying Nausea/vomiting

Diarrhea

Definition: >500 ml every 8 hours or more than 3 stools a day for at least two consecutive days. Relates more to stool consistency than frequency

Diarrhea was a common consequence of enteral feedings when hyperosmolar feedings were routinely delivered via syringe

Occurs in 2 to 63% of enterally-fed pts depending on how defined

Causes/Treatments of Diarrhea Intestinal atrophy due to malnutrition

– EN is the best stimulant for recovery. Increase rate slowly as tolerated

– Albumin infusion is unlikely to be helpful; diarrhea is not caused by low albumin; it is a marker of malnutrition

Bolus feeding in the small intestine: results in dumping syndrome. – Use an infusion pump to regulate flow

The A.S.P.E.N. Nutrition Support Practice Manual, 2nd Edition, 2005

Causes/Treatments of Diarrhea Bacterial overgrowth of intestinal tract or

contamination of the enteral feeding– Avoid prolonged use of broad-spectrum

antibiotics– Use clean technique and closed system in

handling enteral feedings– Limit hang time of open system formulas to 8

hours (4 hours for mixtures)– Change bag and tubing per protocol– Test for C difficile and other pathogens before

using anti-motility agents

Causes/Treatments of Diarrhea Steatorrhea: characterized by frothy,

odiferous stools that float on water; caused by fat intolerance– Use lowfat enteral formula or one with higher

percentage of MCT; pancreatic enzymes may help in pancreatic insufficiency

Causes/Treatments of Diarrhea Lactose intolerance

– Most enteral products are lactose free but this may occur with initiation of full liquid diet. Eliminate milk and dairy products

Drug-induced diarrhea– Meds may cause up to 61% of diarrhea in

tubefed pts due to hypertonicity or direct laxative action (magnesium, sorbitol, potassium). Diarrhea most common with antibiotics. Discuss with MD/pharmacist

The A.S.P.E.N. Nutrition Support Practice Manual, 2nd Edition, 2005

Causes/Treatments of Diarrhea Infusion of hypertonic feeding solutions;

rare unless delivered at very high rate or bolused into small bowel– Try a different product rather than diluting the

original feeding GI disease: such as IBS, short gut, celiac

disease, AIDS– May require PN or specially formulated EN

Treatment of Diarrhea in General Add soluble fiber (such as banana flakes or

Benefiber) or insoluble fiber such as psillium

Consider an enteral formula with added fiber

Use an antidiarrheal agent (loperamide, diphenoxylate, paregoric, octreotide)

Change the formula

Nausea/Vomiting 20% of patients on EN report

nausea/vomiting Often related to delayed gastric emptying

caused by hypotension, sepsis, stress, anesthesia, medications (analgesics and anticholinergics), surgery

Nausea/Vomiting Treatment Consider reducing/discontinuing narcotic

medications Switch to a lowfat formula Administer feeding solution at room temperature Reduce rate of infusion by 20-25 ml/hr Administer prokinetic agent (metoclopramide,

erythromycin, domperidone, bethanechol) Check gastric residuals Consider antiemetics

Metabolic

Fluid and Electrolyte abnormalities Glucose intolerance Ca++, Mg++, PO4 abnormalities Other

Fluid and Electrolyte Disturbances May result from long term nutrition deficits,

acute stress, medications, medical conditions, improper nutrient prescription

Electrolytes lost via stool, urine, ostomy or fistula drainage

Dehydration most common complication (tube feeding syndrome) especially with high protein feeding and insufficient fluid

Hyperglycemia

Often reflects acute stress, infection, medications (especially steroids) or latent diabetes

Macronutrient distribution: is generally not the primary issue; most enteral feeding formulas fall within established guidelines; could try formula lower in carbohydrate

Insulin management

Refeeding Syndrome At risk: when refeeding those with marginal

body nutrient stores, stressed, depleted patients, those who have been unfed for 7-10 days, persons with anorexia nervosa, chronic alcoholism, weight loss

Symptoms: Hypokalemia, hypophosphatemia and hypomagnesemia; cardiac arrhythmias, heart failure; acute respiratory failure

Refeeding Syndrome Correct electrolyte abnormalities (via oral,

enteral, parenteral route) before initiating nutrition support

Administer volume and energy slowly Monitor pulse rate, intake and output, and

electrolyte levels Provide appropriate vitamin

supplementation Avoid overfeeding

Infectious Complications

Formula contamination Unsanitary equipment Failure to follow appropriate protocols re handling

of enteral feedings/changing of bags and tubing

Monitoring of Patients on EN

Electrolytes BUN/Cr Albumin/prealbumin Ca++, PO4, Mg++

Weight Input/output Vital signs Stool frequency/consistency Abdominal examination

Evaluating Adequacy of Support

I’s and O’s (what % of prescribed feeding did patient receive?)

Indirect calorimetry Nitrogen balance Weight Visceral proteins Other

Home Support

Discharge planning– May work with DME company to identify

whether patient is a candidate for home EN, assure availability of product; complete CMN form in conjunction with physician

Patient education– Patients going home on enteral feedings

will need education on food safety, feeding administration, and self-monitoring

Reimbursement

Enteral Support Summary

Preferred method of nutrition support Technology exists to facilitate

implementation Can be successfully employed with careful

patient and formula selection