Surgery

Gastrostomy Tubes (G Tubes)

Introduction

When children are unable to feed by mouth or unable to keep up with their caloric needs with regular feeding, enteric feeding is an option to ensure adequate nutrition. Enteral feeding (ie, feeding via the gastrointestinal tract) is generally preferred wherever possible over parenteral (intravenous) feeding due to the extensive complications associated with long term parenteral feeding.

Overall, there are several key indications for the initiation of enteral feeding in children including

  • inability to eat by mouth safely such as in cases of cerebral palsy or other neurologic dysfunction of oral motor skills
  • Inability to keep up with metabolic demands by mouth such as failure to thrive due to congenital heart disease or other critical illness
  • intestinal malabsorption requiring modified formula such as short gut syndrome or certain inborn errors of metabolism. 

In general, enteral feeding may be performed via nasoenteric tubes (such as a nasogastric tube) or gastrostomy tubes (G tubes). G tubes are generally preferred to nasoenteric tubes if the feeding is predicted to be long term (ie, greater than six weeks to three months depending on the circumstance). 

Certain children may require post-pyloric feeding in which case a gastrojejunostomy tube (GJ tube) can be placed after the initial gastrostomy site is completed.

Gastrostomy tubes require a multidisciplinary approach to care including nutritionists, nursing and physicians.  

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Figure 1. From UCSF Pediatric Surgery [http://pedsurg.ucsf.edu/conditions--procedures/gastrostomy-tubes.aspx]

 

Placement

There are generally two approaches to G tube placement: percutaneous or surgical. Overall, there is a lack of consensus regarding a difference in morbidity and mortality betweenthese two approaches, though percutaneous options are often preferred, as they tend to be more cost effective and faster depending on the context of the individual patient.

Percutaneous                      

  • Two types of procedures are available
                    
    • Percutaneous endoscopic gastrostomy (PEG): done with endoscope into stomach
    • Percutaneous radiologic gastrostomy (PRG): using fluoroscopic guidance, air inserted into stomach via NG tube
  • Performed by radiologist (interventional radiology) or gastroenterologist
  • Generally less expensive and faster than surgical options
  • Unable to perform with certain anatomical abnormalities (eg, esophageal obstruction, bowel between stomach and abdominal wall) or severe obesity

Surgical

  • Performed by a surgeon
  • May be done laparoscopic or open
  • Can be done simultaneously with other procedures if patient will already be undergoing surgery
  • Allows Nissen fundoplication to be performed simultaneously, which may reduce risk of post-operative GERD, though this topic is controversial

 

Management Basics

  • Initial postoperative care of the stoma site will vary slightly depending on the exact procedure performed.
  • G tubes require extensive parental education prior to discharge to ensure that parents are comfortable administering feeds and caring for the tube site itself.
  • Prevention of dislodgement is a key issue in s pediatric population where children may intentionally or unintentionally pull on the tubing. The team must ensure parents have a strategy to secure the tubing so it is not accessible for inadvertent removal. 
  • Once the initial tube is changed post-op, the tubing is typically changed by a medical provider every six months to one year.
  • The external bolster should be rotated at least 180 degrees daily to prevent it from becoming buried in tissue. In terms of fit, it also should be able to move 1 cm in and out to prevent pressure necrosis. As child grows, may need to increase size of spacer between stomach and skin for improved fit.
  • To prevent clogging, tubing should be flushed with small amount of water after every feed.

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Figure 2. G tube sizing diagram from Feeding Tube Awareness Foundation Parental Guide - http://www.feedingtubeawareness.com/ParentGuide.pdf

 

Feeding Strategy

Feeding can be provided with formulas or blended foods. The specific feeding regimen, including the amount of necessary free water, should be determined in conjunction with a nutritionist and physician to ensure adequate calories, vitamins and electrolyte balance. If formula is used, there are a variety of types can that can be used to meet a child’s specific nutritional needs.

Types of Formula

  • Milk protein based: standard formula with intact cow’s milk derived protein
  • Soy protein based: lactose free formula with soy protein
  • Hydrolyzed: partially hydrolyzed amino acids, some medium chain fatty acids, lacose free
  • Elemental: free amino acids, some medium chain fatty acids, lactose free

Bolus or Continuous Feeding

  • Bolus feeds
                       
    • Generally preferred if patient able to tolerate
    • Larger volumes over shorter time replicates traditional meals
    • May not need pump if patient tolerates feeding with gravity infusion
    • Keep patient upright after feeding due to risk of aspiration given large volume
  • Continuous feeds
         
    • For all calories if patient unable to tolerate bolus feeding or supplemental calories done overnight
    • Requires pump

 

Complications

  • Local skin irritation or hypergranulation tissue
  • Leakage
  • Tube malfunction: internal balloon deflation, tube deterioration, clogging
  • Dislodgement
  • Infection
  • Gastrointestinal perforation
  • Gastric outlet obstruction

 

Post-operative GERD management

  • Patients requiring gastrostomy tube placement may be at increased risk for GERD as well as frank aspiration or chronic micro-aspiration during feedings.  This concern is especially relevant for children with neurologic impairment.
  • Some centers routinely perform a fundoplication of the stomach at the same time as G tube placement to decrease risk of GERD, though other centers prefer post-operative medical management.
  • There is currently a lack of consensus in the literature regarding the best management. A 2013 Cochrane review of the literature found no trials comparing fundoplication vs. medical management, concluding that much evidence is still needed to establish the best course of care for these patients.1

 

Parental Resources

The decision to place a G tube in a child can be a challenging one for parents. One systematic review of decision-making of G tube placement among parents found that parental distress often centered on the meanings and associations of feeding by mouth relative to tube feeding2. Mouth feeding was often viewed as pleasurable, social, but also at times difficult, whereas gastrostomy feeding represented a break from normalcy and a visible sign of disability. 

Feeding Tube Awareness Foundation Parental Guide

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http://www.feedingtubeawareness.com/ParentGuide.pdf

  • Describes essential vocab for parents with helpful diagrams of the equipment involved
  • Discusses common myths about feeding tubes
  • Includes helpful form with key questions parents should ask about the details of care with room for provider to write key instructions all in one place (eg, how to feed, medications, who to call for supplies, etc)

 

Feeding Tube Awareness Foundation Website

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http://www.feedingtubeawareness.com/index.html

  • Parent based organization with helpful resources and videos

 

UCSF Pediatric Surgery Webpage

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http://pedsurg.ucsf.edu/conditions--procedures/gastrostomy-tubes.aspx

  • Describes two types of placement
  • Includes links to helpful YouTube videos
  • Section on homecare and troubleshooting main problems

 

References

  1. Vernon-Roberts A, Sullivan PB. Fundoplication versus postoperative medication for gastro-oesophageal reflux in children with neurological impairment undergoing gastrostomy. In: The Cochrane Collaboration, editor. Cochrane Database of Systematic Reviews [Internet]. Chichester, UK: John Wiley & Sons, Ltd; 2013.
  2. Mahant S, Jovcevska V, Cohen E. Decision-Making Around Gastrostomy-Feeding in Children With Neurologic Disabilities. Pediatrics. 2011 Jun 1;127(6):e1471–e1481.
  3. Collier S, Duggen C. Enteral nutrition in infants and children. In: Motil KJ, Hoppin AG, Ed. UpToDate. Waltham, MA: UpToDate; 2015.
  4. DeLegge, MH. Gastrostomy tubes: Placement and routine care. In: Saltzman JR, Lipman TO, Travis AC, Ed. UpToDate. Waltham, MA: UpToDate: 2015.
  5.  Hannah E, John RM. Everything the nurse practitioner should know about pediatric feeding tubes: Everything the NP should know about pediatric feeding tubes. J Am Assoc Nurse Pract. 2013 Nov;25(11):567–77.
  6. DeLegge, MH. Gastrostomy tubes: Complication and their management. In: Saltzman JR, Lipman TO, Travis AC, Ed. UpToDate. Waltham, MA: UpToDate: 2015.