Overview

Definition:
-Percutaneous endoscopic gastrostomy (PEG) is a minimally invasive endoscopic procedure used to place a feeding tube directly into the stomach through the abdominal wall
-It provides a route for long-term enteral nutrition, bypassing the oral cavity and esophagus, and is typically performed under conscious sedation or general anesthesia.
Epidemiology:
-PEG placement is a common procedure worldwide, with thousands performed annually
-Indications are primarily related to dysphagia due to neurological conditions, head and neck cancers, or conditions precluding oral intake
-Patient demographics vary widely based on the underlying pathology, but it is more frequently performed in elderly or debilitated patients.
Clinical Significance:
-PEG placement is crucial for managing patients with long-term nutritional deficits due to impaired swallowing
-It ensures adequate caloric and protein intake, preventing malnutrition, promoting healing, and improving the quality of life for patients with chronic conditions
-For surgical residents, understanding its indications, technique, and potential complications is vital for patient management.

Indications

Primary Indications:
-Severe dysphagia from neurological disorders such as stroke, amyotrophic lateral sclerosis (ALS), Parkinson's disease, or severe traumatic brain injury
-Head and neck malignancies requiring prolonged nutritional support during or after treatment
-Severe esophageal strictures or fistulas unresponsive to other methods
-Neuromuscular disorders affecting swallowing
-Conditions requiring long-term gastric decompression or feeding in critically ill patients.
Contraindications:
-Lack of a suitable gastric lumen or adequate abdominal wall space
-Peritoneal dialysis or ascites
-Significant coagulopathy
-Active upper gastrointestinal bleeding or perforation
-Uncontrolled infection at the insertion site
-Gastric outlet obstruction
-Short life expectancy where risks outweigh benefits.
Relative Contraindications:
-Previous abdominal surgery with adhesions
-Severe immunocompromise
-Severe obesity
-Gastroparesis not responding to medical management.

Preoperative Preparation

Patient Evaluation:
-Thorough medical history and physical examination
-Assessment of nutritional status, including weight loss and laboratory parameters (albumin, prealbumin)
-Evaluation of coagulation profile (PT/INR, aPTT)
-Review of imaging studies to assess gastric anatomy and abdominal wall thickness
-Assessment of airway and respiratory status for sedation/anesthesia.
Informed Consent:
-Detailed discussion with the patient and/or family about the procedure, its benefits, risks, alternatives, and expected outcomes
-Explanation of potential complications such as bleeding, infection, perforation, and tube dislodgement.
Medication Review:
-Discontinuation of antiplatelet agents and anticoagulants as per institutional guidelines
-Review of medications that may affect gastric motility or be affected by the procedure
-Prophylactic antibiotics may be administered.
Bowel Preparation:
-Typically, no extensive bowel preparation is required
-Patients are usually kept nil by mouth for 6-8 hours prior to the procedure
-Clear liquids may be permitted up to 2 hours before if conscious sedation is used.

Procedure Steps

Endoscopic Guidance:
-The stomach is insufflated with air to visualize the gastric mucosa
-The abdominal wall is transilluminated to identify an optimal insertion site, typically in the left upper quadrant, avoiding the spleen and colon
-A small skin incision is made.
Needle Catheter Placement:
-A special needle-catheter unit is advanced through the abdominal wall and gastric wall into the gastric lumen under endoscopic visualization
-A guidewire is then passed through the needle into the stomach.
Dilatation And Tube Insertion:
-The tract is dilated using progressively larger dilators over the guidewire
-Once adequate dilation is achieved, the PEG tube (typically a soft silicone tube with a retention disc) is introduced through the tract into the stomach.
Tube Fixation And Confirmation:
-The retention disc is positioned on the gastric side, and the external bumper is secured against the skin
-The position of the tube is confirmed endoscopically by observing the tube exiting the gastric wall and by the characteristic appearance of the external bumper.
Post Procedure Care:
-The gastrostomy site is cleaned and dressed
-Patients are monitored for signs of bleeding, peritonitis, or tube dislodgement
-Oral intake is usually withheld for a period, and initiation of feeding is guided by institutional protocols.

Postoperative Care

Early Monitoring:
-Vital signs monitoring for hemodynamic stability
-Assessment of the gastrostomy site for redness, swelling, drainage, or bleeding
-Pain management as needed
-Monitoring for signs of peritonitis or abdominal distension.
Feeding Initiation:
-Initial feeding is typically started 12-24 hours post-procedure with a slow infusion of diluted formula
-The rate and concentration of formula are gradually increased as tolerated
-Accurate assessment of gastric residual volume is important.
Tube Care:
-Regular cleaning of the skin around the gastrostomy site to prevent infection and skin breakdown
-Rotation of the tube daily to prevent adherence and skin irritation
-Securement of the tube to prevent accidental dislodgement.
Nutritional Support:
-Ongoing assessment of nutritional status
-Adjustment of feeding regimen based on patient tolerance, caloric needs, and laboratory parameters
-Consultation with a dietitian is often beneficial for optimizing enteral nutrition plans.

Complications

Early Complications:
-Bleeding at the insertion site or within the stomach
-Perforation of the colon or other abdominal organs
-Peritonitis
-Wound infection
-Tube dislodgement
-Gastric leakage
-Pneumoperitoneum
-Localized peritonitis.
Late Complications:
-Gastrocolic fistula formation
-Stomal stenosis or occlusion
-Granulation tissue formation at the stoma site
-Tube malfunction (blockage, breakage)
-Migration of the internal bumper
-Skin erosion or breakdown
-Reflux or aspiration pneumonia.
Prevention Strategies:
-Careful patient selection and pre-procedure evaluation
-Meticulous surgical technique with avoidance of major vessels and adjacent organs
-Adequate site preparation and sterile technique
-Appropriate management of anticoagulation
-Prompt recognition and management of complications
-Regular tube care and stoma site monitoring.

Key Points

Exam Focus:
-Indications for PEG placement, particularly differentiating from nasogastric tubes
-Common insertion site and anatomical structures to avoid (spleen, colon)
-Management of common complications like bleeding and peritonitis
-Role of endoscopy in the procedure
-Timing of initiation of enteral feeding
-Tube types and fixation methods.
Clinical Pearls:
-Transillumination of the abdominal wall is key to safe insertion
-The "pull" technique versus the "push" technique for tube insertion
-Importance of securing the tube adequately to prevent dislodgement
-Serial assessment of gastric residuals is critical to avoid overfeeding and aspiration
-Differentiating leakage from normal stomal drainage.
Common Mistakes:
-Placing the tube too high or too low, risking gastrocolic fistula
-Failing to adequately dilate the tract, leading to tube obstruction
-Inadequate fixation of the tube, resulting in dislodgement
-Delayed recognition of peritonitis or wound infection
-Starting feeds too aggressively or too early post-procedure.