Tube Feeding

Definition: Tube Feeding (TF) is a way to continue providing enteral nutrition when it is not possible or sufficient to perform oral feedings

Background:

Enteral Feeding - nutrition support through the GI tract
Parenteral Feeding - nutrition support delivered through the circulatory system (intravenous)

Enteral nutrition (EN) is preferred over Parenteral Nutrition.
EN benefits:

Earlier gut function
Fewer infections
Lower cost
Shorter hospital stay
delivers nutrients directly to gastrointestinal tract avoiding changes to GI physiology (PN avoids the benefit of the modifying functions of the GI tract and liver)

PN is reserved for patients with GI tract dysfunction preventing adequate nutrient absorption

Indications for Tube Feeding

Children with inadequate or unsafe oral intake and a functioning GI tract
Consider partial EN if the patient is able to absorb some but not all of the required nutrients
Consider supplements in patients with normal swallow function but inadequate intake

Insufficient oral intake

Anorexia
Food aversion
Malabsorption (CF, Short bowel, pancreatic insufficiency)
Increased need (CHD, BPD)

Primary Therapy

Metabolic disease
Intolerance to fasting
IBD

Oral Motor Dysfunction

Prematurity
Neuromuscular disease
Neurologic disease

Abnormal GI tract

Congenital malformations
Esophageal stenosis
Intestinal pseudo-obstruction

Injury/critical illness

Burn
Trauma
Surgery
Sepsis

Contraindications for Tube Feeding

Nonfunctional GI tract (GI obstruction or severe ischemia) is the only absolute contraindication

Intestinal fistulae and severe pancreatitis are no longer considered contraindications

Choice of Enteral Feeding (Access)

Depends on:

anatomy and function of GI tract
indication for feedings
expected duration of feedings
risk of aspiration

Perform Upper GI series to rule our anatomic barriers (malro, gastric outlet obstruction)
Consider aspiration risk in history, if necessary perform barium/fluoro swallow study

Type of tube	Duration	Placement	Notes	Uses
Orogastric	Short term	Bedside	Preterm infants up to 34 wks gestation (gag reflex) OG feeding avoids obstruction of nares in obligate nose breathers Safe to use with basilar skull fractures or those with nasal obstruction (CF)	Feeding Meds Hydration
Nasogastric	Short term	Bedside	Method of choice for those with normal gastric function and low aspiration risk requiring short term nutritional support Simple, low cost, non-invasive Can be used to assess tolerance for feedings prior to placement of long term tube Can be used longer term in those who are able to place the tube each night for feedings Proper positioning should be verified by xray or aspiration of stomach contents (not by abd auscultation)	Feeding Meds Hydration
Nasointestinal	Short term	Fluoroscopic	Easy displacement Can be weighted or unweighted (no advantage to using erythromycin, metoclopromide, or weighting with regard to passing pylorus with peristalsis)	Feeding Hydration
Gastrostomy	Long term > 3 mo	Surgical	Not ready for immediate use (several days) Creates formal attachment b/w stomach and abd wall Risk of infection (intra-abdominal abscess or peritonitis) Prone to local irritation (irritation, granulation, infection)	Feeding Meds Hydration
Percutaneous endoscopic gastrostomy (PEG)	Long term	Endoscopic or radiologic	Can be used 4 hrs after placement 2 months until tract maturation Replacement after tract matures	Feeding Meds Hydration
Low profile device	Long term	Surgical or endoscopic but then bedside (or home)	More convenient, easier to care for, less irritation	Feeding Meds Hydration
Gastojejunostomy or percutaneous endoscopic jejunostomy (or anything beyond pylorus)	Long term	Endoscopic, radiologic, or both	Possible to access stomach and small bowel easily dislodged	Feeding Hydration Limits reflux and aspiration
Jejunostomy	Long term	Surgical or endoscopic	No access to stomach (often needed for venting)	Feeding Hydration Limits reflux and aspiration

NG Tube Sizing

0-3mo: 5-8Fr
6mo: 8-10Fr
1yr: 10Fr
10yr: 10Fr
12yr: 12Fr
14yr: 14Fr

PEG Tube kit:

external bolster
safety trocar cannula
safety shielded scalpel
retrieval snare
Y-port
C-clamp

Low profile devices have either a mushroom shaped bolster or a fluid filled balloon

Prepyloric vs postpyloric feeding

Prepyloric feeding

Benefit

simulates normal feeding/digestive processes

can hold bolus feedings (approximates normal meals)

promotes better gastric contractility (cyclic and associated with peaks and troughs of insulin)

protective effect against hyperosmolar formulas (duodenal osmolar receptors will regulate gastric emptying by retaining hyperosmolar fluids until they are isoosmotic) This decreases dumping risk

dumping syndrome can result when high volume hyperosmolar fluids enter duodenum

Risk

Potential risk of PNA from aspiration of stomach contents

exercise caution in administering prepyloric feeds in patients with gastroparesis or history/high risk of aspiration

Postpyloric feeding

Consider in patients with:

high risk for aspiration (esp neuro impaired/ those who cannot protect airway)
intolerance to gastric feeding
recurrent emesis
severe GER

Can decrease but not eliminate risk for aspiration
Some postpyloric tubes have a gastric port for venting and administration of meds
Postpyloric feedings must be administered slowly over most of the day
Major disadvantage is placement of tube and migration of tube post-placement as well as potential occlusion of smaller postpyloric tubes

Bolus or Continuous

Method of delivery depends on;

Type of tube
Medical condition (ambulatory, ICU, etc)
Expected tolerance of feeding
Nutritional requirements
Support (parents, acceptance, availability, cost, etc)

Bolus

More physiologic
Preferred for ambulatory patients
Feeding volume for 24hr period is determined and then divided into 4-6 bolus feeds
Watch for nausea, vomiting, diarrhea, and abd distention

Continuous

Requires infusion pump
Administered over 8-24hrs
May be used in ambulatory patients overnight or even to supplement bolus feeds

Maintenance

Changing G-tubes

Some centers recommend changing G-tubes every 3 months
Others change based on functionality

G-tubes can be replaced with G-J tube (usually radiographically) after tract has matured (2mo)

Complications

Mechanical Complications

Complications	Potential Cause	Tx
Tube Breaks	Manufacture defect Mishandling Worn-out	Repalce tube or part
Cannot rotate tube, dimples skin, skin with intermittent irritation	Tube too tight	Resize and change to appropriate size If balloon present, check volume (do not overfill)
Buried bumper, cannot rotate tube but feeds flow freely into stomach	Tube too tight and becomes embedded in the gastric wall (tube is too small or mechanical traction on the tube)	Assess and replace tube or contact team that placed tube if not Peds GI
Clogged Tube	Failure to rinse tube after feedings Delivery of crushed meds through tube	Replace tube Attempting to force fluids through a clogged tube may result in rupture Change meds to liquid if possible, educate caregiver regarding flushing tube
Dislodged	Handling by patient	Reposition
Tube hangs out onto abdominal wall	Tube too long or internal balloon issue	Resize and replace with appropriate sized tube If balloon present, ensure that it is intact and correctly filled
Leaking at stoma site	Assess tube size, Infection, or underfilled balloon	Place correct - sized tube Treat for infection Reassess balloon volume and correct if necessary
Granulation tissue	Caused by repetitive mechanical trauma	Cauterize with silver nitrate Assess tube for size Educate about handling of tube

Metabolic Complications

Dehydration

Too little free water or hyperosmolar or high protein formula

increase free water
reassess formula

Hyperglycemia

Diabetic with changed insulin requirement

Monitor Blood Glucose
Reduce carb content
Adjust insulin dose

Hyperkalemia

High potassium formula
Renal insufficiency
IV potassium
Acidosis

Change formula
Give Potassium binder
Insulin/glucose
Stop or decrease IV potassium
Correct acidosis

Hyperphosphatemia

Renal insufficiency

Change formula to renal-specific formula
Give phosphate binder
Calcium supplements

Hypokalemia

Malnutrition
Diarrhea
Insulin Administration

Monitor electrolytes
Fluid and electrolyte replacement
Assess insulin dose

Hypophosphatemia

Refeeding syndrome
Insulin administration

Phosphorus supplements
Hold feedings if phosphorus <1.0 mg/dL (<32mmol/L) until correction begins
Assess insulin dose

Hyponatremia

Overhydration

Adjust fluids

Acute rapid weight gain

Fluid overload

Adjust fluids

Rapid excessive weight gain

Too many calories

Reassess prescription for enteral feeding:
Formula concentration, Rate, and Length of feeding

Inadequate weight gain

Not enough calories

Reassess prescription for enteral feeding:
Formula concentration, Rate, and Length of feeding

Gastrointestinal Complications

Complications	potential cause	Tx
Diarrhea, General	Osmotic load Infection Contamination of feed	Assess formula composition Assess method of administration, storage, handling Review all medications, esp liquid meds (sorbitol, etc) Reduce rate of delivery Assess for infection
Diarrhea, GI tract abnormalities	Flat villous lesion Short bowel pancreatic insufficiency	Define GI problem and Tx accordingly Pancreatic Supplements Bulking agents Reduce rate of delivery
Malabsorption	Define Cause	Tx identified cause Consider increased use of medium chain Triglycerides Elemental or semi-elemental formula
Vomiting	GI obstruction Tube malpositioned (if foley cath, see if balloon is occluding the pylorus) Meds administered with feeding Patient positioning Delayed gastric emptying Post fundoplication	Assess and Tx accordingly Reposition tube or change type Do not administer meds with feeds Reposition patient Reduce rate of delivery / consider continuous feeds Erythromycin trial Try Nasojejunal if s/p fundoplication
Constipation	Inadequate fluids Inadequate fiber Inactivity Obstruction Fecal impaction	Assess fluids Consider fiber containing formula Disimpact as necessary Consider osmotic stool softener
Skin is erythematous, warm, has visible pus or attempt to turn tube causes pain	Infection	Culture Broad spectrum Abx Educate on proper tube care and hygiene
Abdominal distention	GI obstruction Constipation Aerophagia Bacterial overgrowth	Treat obstruction or constipation Vent gastric port Consider Ferrell valve bag which allows continuous venting and provides reservoir for formula

Discharge planning

When feeding is established and tolerated and improvement noted (clinical response), discharge planning should begin

Parent/Caregiver training

Discuss diagnosis and need/indication for tube feeding
Handling of equipment
Managing feedings (schedule, preparation, administration)
Monitoring for and troubleshooting complications
When to call health care team, when to seek emergent medical attention

Arrange for supplies and necessary equipment (DME order)
Home nursing care
Follow up evaluations

Posttraumatic Feeding disorder

Condition caused by a traumatic oropharyngeal event such as intubation or prolonged tube feeding

References:

PIR volume 38 no 1 Jan 2017 pp23-33