Indications for PEG tube
Feeding – there are several groups of patients that receive PEG tubes. One group is patients with disruption, obstruction (from cancer), or malfunction (achalasia, multiple sclerosis, scleroderma) of the esophagus. Patients with severe head trauma with residual deficits at risk of aspiration are candidates. Additional patients who can not take normal feeds and may require PEG tubes are patients on the ventilator, spinal cord injury patients, dementia patients, and cerebral palsy patients.
Gastric decompression – patients with the presence of chronic, severe bowel obstruction (tumor, adhesions) often receive PEG tubes to decompress the obstruction and the need for a nasogastric tube, which can be uncomfortable for patients
Abnormal anatomic position of the stomach (e.g., hiatal hernia or malrotation) or abdominal wall, lack of sufficient abdominal wall, abdominal wall infection or burn generally precludes placement of a PEG tube
Many of the conditions once thought to be contraindications have been discarded. Although increasing the risk of the procedure, patients with ascites and previous surgery can be considered for PEG tubes.
Preoperative workup and preparation
Antibiotics – one dose of preoperative antibiotics is typically given before PEG tube placement as prophylaxis against mouth flora being carried by the scope and infecting the abdominal wall track.
Laboratory – typically a blood test to measure platelet count (should be greater than 50,000/dl), PT and INR (should be lower than 1.5) and PTT (should be normal) is obtained.
Surgical prep – usually betadine or chlorhexidine on anterior abdominal wall.
Position – supine (on their back)
1 cm vertical incision at site of exit of PEG tube from anterior abdominal wall
Surgical Details of Procedure
1. Topical anesthesia administered to back of oropharynx if patient is awake.
2. Gastroscope is inserted through a mouth guard and down the esophagus to the stomach.
3. Stomach is fully inflated with air to displace the adjacent colon inferiorly and push the anterior wall of the stomach against the inside of the abdominal wall over the maximal area possible.
4. The lighted end of the gastroscope is turned upward toward the anterior stomach wall.
5. The room lights are dimmed and the site of transillumination of the scope is noted and marked. It should be halfway between the umbilicus and the left costal margin.
6. The gastroscope is then pulled back into the stomach and palpation is done on the outside of the anterior abdominal wall and confirmed by the view from the gastroscope.
7. Local anesthesia is injected at the marked skin site and a 1 cm vertical incision is made.
8. A 16 gauge intravenous needle is inserted through the skin, abdominal wall and the anterior wall of the stomach in a fairly rapid manner to decrease the chance of the anterior stomach wall “floating away” from the abdominal wall.
9. The inner needle is withdrawn the cannula left in place.
10. A long silk of nylon suture is placed through the cannula and into the stomach.
11. The polypectomy snare is inserted through the gastroscope and into the stomach.
12. The polypectomy snare is used to grab the suture and then the suture, snare, and scope are pulled out (through the mouth).
13. A tapered Pezzer catheter (aka mushroom catheter) or PEG tube is then tied to the suture end at the mouth and a sterile lubricant is applied to the tapered end.
14. Usually gentle but firm pressure the end of the suture at the abdominal wall is then used to pull the catheter down the esophagus and into the stomach and out the abdominal wall.
15. The gastroscope is then reinserted to insure that PEG is positioned up against the wall of the stomach and to inspect for bleeding or stomach tears.
16. An external crosspiece is then fitted onto the abdominal wall to hold the PEG tube in place.
17. A non-absorbable suture is used to additionally fasten the PEG tube in place.
18. The skin incision is left open with placement of a topical antibiotic.
The PEG tube is left to open drainage for 24 hours. Small volume tube feedings may then be started (even continous infusion or bolus). The PEG tube must remain in place for a minimum of four weeks (preferably six) before it is removed or changed to allow for healing of the tract and fusion of the stomach to the anterior abdominal wall.
Infection – this can occur due to the skin incision and the risk of mouth flora contaminating the wound. The risk is increased if the PEG tube cross bare is “too tight” against the skin. Early, severe infection is very suspicious for a colon injury.
Displacement of the stomach away from the abdominal wall – this in effect creates a hole in the stomach with free drainage into the peritoneal cavity. This is a surgical emergency and always requires a trip to the operating room and a laparotomy.
Puncture of the bowel – the PEG procedure is “blind” in the sense that there is no visualization of the space between the stomach and anterior abdominal wall and it is possible for colon or small bowel to be inadvertently punctured by the needle.