PEG Feeding Tubes - Indications and Management

Percutaneous endoscopic gastrostomy (PEG) feeding tubes were first described in1980. Early studies typically demonstrated it to be an easy and safe technique when compared with the available alternatives such as open gastrostomy.¹ PEG feeding tubes are increasingly used for long term enteral nutrition. It is used where patients cannot maintain adequate nutrition with oral intake. Neurolgical conditions are most commonly associated with such disability and constitute the most common indication for PEG. Its simplicity has led some to concern about use when there is little or no clinical benefit.^2,3 Care needs to be taken when looking at studies on use of PEG as there are differences in patient selection which affect for example outcome measures and complications. There are sometimes ethical factors to consider (see below).⁴ Several court cases have indicated that PEG should be used in patients who have lost the capacity for self determination.

It is important that patients are selected carefully for PEG.² Indications include difficulties with oral inake often where obstruction to the upper airway or gastrointestinal tract makes passing a nasogastric tube difficult. PEG tubes are used in:

• Head and neck cancers. PEG has become the most acceptable and safest method for long term feeding support.^5,6 It is useful particularly when surgery is extensive and when combined with chemotherapy, radiotherapy or both.⁶
• Malignant bowel obstruction⁷ including oesophageal cancer.⁸
• Neurological conditions are the most common indications for PEG and include:^9,10
  • Acute stroke (usually the most common indication for PEG and often vertebrobasilar strokes)²
  • Disorders of swallowing
  • Multiple sclerosis
  • Neurosurgical disease
  • Parkinson's disease
  • Brain tumours
  • HIV encephalopathy
  • Neonatal encephalopathy
  • Amyotrophic lateral sclerosis¹¹
  • Dementia in which use is common but controversial
  • Head injury patients.
• AIDS and HIV encephalopathy. Nutritional status in one study was improved but this is not known to translate into either better survival.¹²
• Crohn's disease.¹³
• Burns patients.¹⁴

PEG insertion is safest with careful patient selection. PEG insertion should be avoided in:¹⁵

• Acutely ill patients¹⁶
• Patients with short life expectancy
• Patients with severe coughing.

PEG insertion:

• Can be done as an outpatient procedure
• Takes on average less than 20 minutes
• Requires sedation and of course endoscopy
• Can be with either 'push' or 'pull' insertion
• 'Pull' insertion more usual¹⁷ and best given with antibiotic prophylaxis¹⁸
• PEG tubes made of polyurethane or silicone with a retaining mechanism
• For feeding longer than 1 month a silicone button (flush with the skin) is used
• Retained usually with intragastric balloon
• Can be done by suitably trained and supervised nurse practitioners¹⁹
• Antibiotic prophylaxis now usually recommended.^20,21,22

There are alternative methods of gastrostomy tube insertion to PEG. They are:

• Laparoscopic insertion
• Open surgical technique
• Radiologically guided percutaneous insertion (PRG).

There are reports over the years since introduction of PEG in the 1980s favouring one method over another but there was an early trend in favour of PEG.²³ A small study from Ireland and one from London favour PRG in patients with amyotrophic lateral sclerosis as it avoids the need for sedation or endoscopy.^24,25 One meta-analysis suggested a higher success rate with PRG than with PEG, and less morbidity than either PEG or surgery.²⁶ However a more recent comparison of a relatively small number of endosopic, surgical and laparoscopic placement favoured PEG²⁷ and another favoured PEG over PRG.²⁸ A literature review suggested PEG as the procedure of choice for placement of gastrostomy tubes.²⁹ A recent prospective randomised trail favoured PEG over surgical gastrostomy insertion.³⁰ There is some evidence that polyurethane PEGs are less troublesome than silicone PEGs (less tube deterioration, less blockage).³¹ PEG is preferred in trauma patients.³² Antibiotic prophylaxis for PEG insertion appears to reduce the incidence of wound infection.^21,22 Laparoscopic insertion was considered preferable to PEG by one study in children with PEG insertion having higher complication rate in children and often requiring repeat anaesthetics.³³ An earlier study in children showed similar results for surgical, PRG and PEG insertion but did not look at the laparoscopic technique.³⁴ A recent study from Norway found PEG insertion safe and very well tolerated by children and parents but made no comparison with other techniques.³⁵

Benefits reported include:

• Well tolerated (better than nasogastric tubes)
• Improved nutritional status¹⁰
• Ease of usage over other methods (nasogastric or oral feeding) reported by carers¹⁰
• Satisfactory use by home carers^10,36
• Low incidence of complications
• Reduction in aspiration pneumonia associated with swallowing disorders³⁷
• Cost effective relative to alternative methods particularly when reasonably long survival expected.³⁸

• Education of carers and patients is essential to reduce tube problems and complications.³⁹
• A number of studies indicate the support and education of patients should be multidisciplinary involving:
  • Nurses (wound care and ostomy expertise)
  • Dietitians (nutritional advice and support).
• Ongoing care involves:
  • Inspection and maintainance of the access device (see below)
  • Wound care advice
  • Nutritional support and advice.

Care of PEG tube

This routine care can be performed by the patient and/or the carers with suitable training. After about 10 days following insertion asepsis is not required.

• Examine skin around site for infection/ irritation
• Note measuring guide number at end of external fixation device
• Remove tube from fixation deviceand ease away from abdomen
• Clean stoma site with sterile saline
• Dry area with gauze
• Rotate gastrostomy tube to prevent adherence to sides of tract
• Re-attach external fixation device to abdomen
• Attach gastrostomy tube gently to fixation device and position as before according to mark/number on tube
• Avoid use of bulky dressings.

Morbidity and mortality are generally considered to be low with studies reporting major complications between 3% and 8% of patients and minor in around 14%.^15,40 Mortality from the procedure itself is very low and less than 1%.⁴¹ However other studies report higher and rising complication rates.³ These often relate to the underlying illnesses with for example higher rates of wound infections in malignant disease⁹ and may also reflect a lowered threshold for PEG insertion.³ Major complications include:

• Gastric perforation¹⁰
• Gastrocolic fistula¹⁰
• Internal leakage³²
• Dehiscence³²
• Peritonitis³²
• Aspiration pneumonia
• Subcutaneous abscess
• Buried bumper syndrome (migration of the internal bumper of the PEG tube into the gastric or abdominal wall).

Minor complications include:

• Tube problems:
  • Tube blockages
  • Tube dislodgements
  • Tube degradation¹⁰
  • External leakage
  • Unplanned removal.³²
• Site infections (common but rarely serious.¹² There have been studies to determine whether prophylactic antibiotics prevent such infections.²¹)

The incidence of dementia is increasing and maintaining nutritional status can become difficult and expensive as the disease progresses. Patients with dementia often receive feeding tubes when hospitalised for acute illnesses contrary to their wishes and those of their families. Research indicates that there is little benefit from aggressive nutritional support with no measurable improvements in life expectancy, weight or reduction in complications (for example pressure sores and aspiration).⁴² PEG tubes are often used inappropriately because of unrealistic and inaccurate expectations of what they can achieve.⁴³ Feeding tubes have been too often inserted in patients who will not benefit from them and whose quality of life in a terminal stage of illness will be adversely affected. Multidiciplinary care and educational programmes have been found to reduce the numbers of patients receiving feeding tubes inappropriately.⁴⁴ Some hospitals now have nutrition teams and PEG requests are reviewed by this team and a consultant to assess whether PEG insertion is appropriate. The use of advance directives has also been suggested to allow patients with dementia to refuse insertion of a feeding tube in advance of the dementia progressing.⁴²

There have been few long term follow up studies. One in 1997⁴⁰ showed 49% died and 17% returned to oral feeding from a population which included roughly half the patients with a diagnosis of cancer and half with a non-cancer diagnosis. Clearly the overall mortality rate after PEG insertion is high because of the underlying medical problems.⁴¹ A five year prospective study showed few complications from the procedure itself and improved nutritional status.³