PEG insertion

Percutaneous Endoscopic Gastrostomy

• Equivalent results to traditional gastrostomy with lower cost and discomfort

Indications

• Only consider when it is likely to improve the patient's long-term functional outcomes or quality of life
• Long-term feeding in patients unable to eat but with functional GIT
• Unpalatable medications for children
• Night-time supplementary feeds for IBD patients
• Returning external biliary drainage to GIT
• Gastric decompression in radiation enteritis or carcinomatosis

Contraindications

• Caution with upper abdominal surgery - traditionally, upper midline laparotomy is a contraindication, requires open gastrostomy
• Severe malnutrition
• Life expectancy <30 days
• Treat oral candidiasis prior to insertion
• Specific conditions
  • Advanced dementia - does not improve longevity or QoL - prefer risk feeding
  • Prognosis <3 months (apart from venting)
  • Anorexia nervosa - does not address psychiatric illness
  • Sepsis - risk of exacerbating - NGT feeds until sepsis resolves
  • Varices/Portal HTN - risk of bleeding - prefer surgical gastrostomy
  • Upper GIT malignancy requiring surgery - prefer jejunostomy
  • Peritoneal carcinomatosis
  • Ascites/PD - high risk for poor tract formation and peritonitis

Equipment

• 20Fr is probably a good starting point, especially for first tubes
• Some suggest using 24Fr for first tube
• Austin guidelines are for >20Fr for venting, and 12-16Fr for feeding
• Low-profile tubes potentially have lower risk of catching/pulling, and cosmetically better. Patient needs to have stable weight.
• Silicone tubes require replacement every 6-12 months, and are susceptible to candida colonisation. Polyurethane tubes are thinner-walled, so smaller external diameter can be used, and can last many years with good care, and are less susceptible to candida.

Endoscopic technique

• Mark skinfolds, bra, waistline if possible prior to procedure
• IV Abx, supine, clip epigastric hair, prep epigastrium, drape
• Sedation - either opioid + benzodiazepine or propofol
• Gastroscopy - rapid inspection of pylorus and duodenum
• Confirm appropriate to proceed endoscopically:
  • Transilluminate towards skin to pinpoint optimal access point
  • One to one movement between external and internal
  • If unable to prove these, will need laparoscopic gastrostomy
• Insert a needle with LA in syringe through to stomach, withdrawing, with no bubbling until stomach (otherwise there's probably some bowel in the way). Withdraw the needle, leaving the sheath in situ.
• Feed the included guidewire/loop suture through the sheath, then 'grab' it from the inside with the included snare, and pull it out through the mouth.
• Attach PEG tube to guidewire, lube up the top of the PEG and pull back into stomach (follow it down with scope) then out through skin
• Head of the catheter should come to lie in loose contact with gastric mucosa - slight tension, but not tight enough to risk gastric ischaemia - some say should still be able to turn it
• Cut PEG at the 'x' (about 20cm from skin) and then attach flange with butterfly clip so the flange is 5-10mm from skin; then place a gauze underneath, and attach the nozzle to the end
• Record how far in at skin
• No need to suture tubes with internal fixator (bolster or balloon)

Surgical-assisted technique

• Laparoscopic access
• Perform any required adhesiolysis/exposure of anterior stomach
• Place PEG kit needle/sheath through abdominal wall directly into stomach, then feed through guidewire/snare
• Endoscopist grasps wire and pulls out through mouth
• Proceed with remainder of usual PEG procedure

Surgical gastrostomy

• Laparoscopic access to abdomen
• Tent stomach up with two posterior quadrant sutures with EndoClose
• Purse-string
• Pass PEG through abdo wall and then through stomach
• Inflate balloon and tie purse-string
• Anterior two quadrant sutures

Radiological technique

• Can be performed under light sedation and LA
• Ideally use NGT to distend stomach with air, so not favoured with complete oesophageal obstruction
• Can insert initial gastrostomies and gastro-jejunostomies

Post-insertion instructions

• NBM and nil by device for two hours post-insertion, then flush with 30mL water and observe for uncontrolled pain, resistance to flushing or leakage
• If no complications, commence 30mL water flushes hourly for four hours, then device is ready to use for feeding
• Dietician education and Home Enteral Nutrition program (at Austin)
• BD clean at skin with saline/peroxide
• Venting gastrostomies can be used immediately
• Rationalise medications down tube to liquid/soluble/dispersible
• Next day, change dressing (gauze under baseplate)

Complications

• Leakage
  • True significant leakage due to a technical error tends to present in first few days
  • Can present as either asymptomatic leakage of gastric fluid around the tube to skin, or leakage to peritoneum causing overwhelming peritonitis and sepsis
  • Causes:
    • Inadequate fixation of the stomach against the inner abdominal wall
    • Separation of the two (due to ischaemia and necrosis of the gastric wall from an over-tight seal)
    • Tube migration
    • Distal obstruction
    • Balloon deflation/rupture
    • Incorrectly-sized device
    • DGE
    • Constipation
    • Increased intra-abdominal pressure
  • Diagnosis - minor pneumoperitoneum is not diagnostic, because it can be present for 1-2 weeks normally. However, large-volume pneumoperitoneum is highly suggestive of leak. If in doubt, do a contrast study down the PEG.
  • Management of
    • If no intra-peritoneal leakage on contrast study, 'rest' the tube for a week and give IV Abx, to allow it to seal. Then repeat the contrast study before feeding.
    • If there is obvious peritoneal leakage, manage based on clinical scenario - operate if there is peritonitis or sepsis. Can be done laparoscopically.
      • If everything looks healthy at operation, can do a purse-string around the tube and re-fix to the abdo wall
      • If stomach looks 'bad', remove the tube and staple/suture off the defect, and consider replacing the tube in a healthy location
    • Late leaks - generally behave like a controlled gastro-cutaneous fistula, but can become uncontrolled and cause peritoneal sepsis
• Buried bumper
  • When the internal fixator erodes past the stomach wall, and instead sits within the stomal tract
  • Risk factors - frequent and inadvertent device traction, rapid weight gain, lapses in exit site care
  • Presentation - leakage, blockage, infection/inflammation at exit, pain, inability to advance device within tract
• Bleeding
  • Immediate post-procedural bleeding can be controlled with gentle traction on tube
• Minor irritation to skin - close attention to cleansing
• Fungal infection - antifungal powders/creams
• Infection may reflect abscess - can incise to look for pus, and give antibiotics
  • Always consider and exclude a necrotising infection
• Migration is generally related to excessive traction and subsequent necrosis
• Gastrocolic fistula - if colon is pierced at insertion
  • Frequently patient has diarrhoea
  • Free leaks/abscesses must be controlled, but fistulas
  • PEG-associated gastrocolic fistulas may subside when the tube is pulled out, but not necessarily
• Abdominal sepsis following PEG
  • Stop feeds, get a tubogram
• PEG pulled out
  • Gastrostomy:
    • If early (within four weeks), before a tract has formed, give Abx and NGT, and rebook procedure for 5-7 days
      • Can also attempt to reinsert if it seems like there is a decent tract and no peritonitis or sepsis, but also put in an NGT and 'rest' the stomach for a week on Abx
    • 4-6 weeks - bedside replacement with similar-sized tube, then confirm no leak with tubogram before using again
    • >6 weeks: put in a Foley 20Fr as a temporising measure and then replace it with a feeding tube when available, safe to use straight away if flushing well and pH of aspirate <=5
• Delirious patient pulling PEG out - try an abdominal binder
• Pain
  • Consider poor tube positioning - too close to costal margin
• Blocked tube
  • See separate topic under 'nutrition'

Alternatives

• Fluoro-guided - Can't do as big of a tube, gets blocked more often, less reliable internal fixation
• Laparoscopy-assisted PEG
• PEG-J (jejunal extension)

PEG removal

• At least six weeks post-insertion
• Alternative route available - consider dietician/SP input
• Fast for two hours prior and six hours post
• Consider staged removal of larger devices (>20Fr)
• PPI cover for tracts at higher risk of forming a persistent gastrocutaneous fistula (main proven risk factor is insertion time >8 months)
• Techniques:
  • Balloon deflation and pull
  • Traction removal
  • Cut and push (where traction removal is not possible, and the patient should be able to pass the internal component in stool) - usually do an x-ray one week later