What is Esophagogastroduodenoscopy (EGD)?

Esophagogastroduodenoscopy (EGD), also called by various other names, is a diagnostic endoscopic procedure that visualizes the upper part of the gastrointestinal tract down to the duodenum. It is considered a minimally invasive procedure since it does not require an incision into one of the major body cavities and does not require any significant recovery after the procedure (unless sedation or anesthesia has been used). However, a sore throat is common.

Diagnostic features

• Unexplained anemia (usually along with a colonoscopy)
• Upper gastrointestinal bleeding as evidenced by hematemesis or melena
• Persistent dyspepsia in patients over the age of 45 years
• Heartburn and chronic acid reflux – this can lead to a precancerous lesion called Barrett’s esophagus
• Persistent emesis
• Dysphagia – difficulty in swallowing
• Odynophagia – painful swallowing
• Persistent nausea
• IBD (inflammatory bowel diseases)

Surveillance

• Surveillance of Barrett’s esophagus
• gastric ulcer or duodenal ulcer
• Occasionally after gastric surgery

Confirmation of diagnosis/biopsy

• Abnormal barium swallow or barium meal
• Confirmation of celiac disease (via biopsy)

Therapeutic Techniques

• Treatment (banding/sclerotherapy) of esophageal varices
• Injection therapy (e.g., epinephrine in bleeding lesions)
• Cutting off of larger pieces of tissue with a snare device (e.g., polyps, endoscopic mucosal resection)
• Application of cautery to tissues
• Removal of foreign bodies (e.g., food) that have been ingested
• Tamponade of bleeding esophageal varices with a balloon
• Application of photodynamic therapy for treatment of esophageal malignancies
• Endoscopic drainage of pancreatic pseudocyst
• Tightening the lower esophageal sphincter
• Dilating or stenting of stenosis or achalasia
• Percutaneous endoscopic gastrostomy (feeding tube placement)
• Endoscopic retrograde cholangiopancreatography (ERCP) combines EGD with fluoroscopy
• Endoscopic ultrasound (EUS) combines EGD with 5–12 MHz ultrasound imaging

Newer interventions

• Endoscopic trans-gastric laparoscopy
• Placement of gastric balloons in bariatric surgery

Complications

The complication rate can be about 1 in 1000. They include:

• aspiration, causing aspiration pneumonia
• bleeding
• perforation
• cardiopulmonary problems

When used in infants, the esophagogastroduodenoscopy (EGD) may compress the trachealis muscle, which narrows the trachea. This can result in reduced airflow to the lungs. Infants may be intubated to make sure that the trachea is fixed open.

Procedure

The tip of the endoscope should be lubricated and checked for critical functions including tip angulations, air and water suction, and image quality.

The patient is kept NPO or NBM (nothing by mouth) that is, told not to eat, for at least 4 hours before the procedure. Most patients tolerate the procedure with only topical anesthesia of the oropharynx using lidocaine spray. However, some patients may need sedation and the very anxious/agitated patient may even need a general anesthetic. Informed consent obtains before the procedure. The main risks are bleeding and perforation. The risk increases when a biopsy or other intervention is performed.

The patient lies on his/her left side with the head resting comfortably on a pillow. A mouth-guard is placed between the teeth to prevent the patient from biting on the endoscope. The endoscope is then passed over the tongue and into the oropharynx. This is the most uncomfortable stage for the patient. Quick and gentle manipulation under vision guides the endoscope into the esophagus.

Endoscope

The endoscope, gradually advanced down the esophagus making note of any pathology. Excessive insufflation of the stomach is avoided at this stage. The endoscope quickly passed through the stomach and through the pylorus to examine the first and second parts of the duodenum. Once this has been completed, the endoscope is withdrawn into the stomach and a more thorough examination is performed including a J-maneuver. This involves retro flexing the tip of the scope so it resembles a ‘J’ shape in order to examine the fundus and gastroesophageal junction. Any additional procedures are performed at this stage. The air in the stomach, aspirated before removing the endoscope. Still, photographs can be made during the procedure and later shown to the patient to help explain any findings.

The endoscope used to inspect the internal anatomy of the digestive tract, in its most basic use. Often inspection alone is sufficient, but biopsy is a valuable adjunct to endoscopy. Small biopsies passed through the scope and allows sampling of 1 to 3 mm pieces of tissue under direct vision. The intestinal mucosa heals quickly from such biopsies.

Equipment

Endoscope

• Non-coaxial optic fiber system to carry light to the tip of the endoscope
  • A chip camera at the tip of the endoscope – this has now replaced the coaxial optic fibers of older scopes that were prone to damage and consequent loss of picture quality
  • Air/water channel to clean the lens using the water and air channel for drying the lens itself and to insufflate the esophagus and the stomach during the operation to prevent from collapsing the track to better vision in the procedure
  • Suction/Working channels – these may be in the form of one or more channels
  • Control handle – this houses the controls
  • Umbilical Cords that connected to the light source and video processor to supply the endoscope with suction and air pressure and water for (suction and irrigation process) and light to transmit in the body to deliver the video signal to the processor to show the live image on the monitor

Stack

• Light source
  • Suction
  • Electrosurgical unit
  • Video recorder/photo printer

Instruments

• Biopsy forceps
  • Snares
  • Injecting needles

Chemical agents

• Dimethicone
  • Acetate
  • Indigo carmine