Esophagogastroduodenoscopy 

Esophagogastroduodenoscopy (EGD) is a procedure during which a small flexible endoscope is introduced through the mouth (or with smaller caliber endoscopes, through the nose) and advanced through the pharynx, esophagus, stomach, and duodenum. An enteroscope, a longer endoscope, can be introduced beyond the ligament of Treitz into the jejunum. EGD is used for both diagnostic procedures and therapeutic procedures. Most modern endoscopes now use a video chip (charged coupled device) for better imaging, as opposed to the older endoscopes, in which fiber optics are used for image transmission. The images below were obtained during EGD.

In the United States, the procedure is usually performed while the patient is under conscious or moderate sedation, although it can be performed with only topical anesthesia (common practice in Europe and Asia). General anesthesia is often used in a selected group of patients who are difficult to sedate due to chronic narcotics intake. The procedure is usually performed in a dedicated endoscopy unit in the hospital or outpatient office setting but can also be done in the emergency department, intensive care unit, or operating room using portable endoscopy carts. Using various types of equipment and endoscopes, endoscopic ultrasound (EUS), endoscopic retrograde cholangiopancreatography (ERCP), and small bowel enteroscopy can also be performed.

• Diagnostic evaluation for signs or symptoms suggestive of upper GI disease (eg, dyspepsia, dysphagia, noncardiac chest pain, recurrent emesis)
• Surveillance for upper GI cancer in high-risk settings (eg, Barrett esophagus,^[1] polyposis syndromes)
• Biopsy for known or suggested upper GI disease (eg, malabsorption syndromes, neoplasms, infections)
• Therapeutic intervention (eg, retrieval of foreign bodies, control of hemorrhage, dilatation or stenting of stricture, ablation of neoplasms, gastrostomy placement)

• Contraindications include possible perforation, medically unstable patients, or unwilling patients.
• Relative contraindications include anticoagulation, pharyngeal diverticulum, or head and neck surgery.
• Diagnostic EGD is considered a low-risk procedure for bleeding in patients on anticoagulants and, therefore, can be performed without adjustment of anticoagulants prior to the procedure. However, if polypectomy is contemplated or conceivable, then the patient's coagulation profile should be normalized. A risk of retropharyngeal hematoma also may be present in patients with severe coagulation abnormalities. Certain therapeutic procedures (ie, dilations, percutaneous gastrostomy, polypectomy, endoscopic sphincterotomy, EUS-guided fine-needle aspiration, laser ablation, coagulation) are considered high-risk procedures for bleeding, and adjustment of anticoagulation may be necessary.

Sedation

• In the United States, conscious sedation and topical anesthesia are commonly used for EGD. The use of monitored anesthesia care and propofol (Diprivan) is gaining wide acceptance because of the short recovery time. However, in many other countries, EGD is performed with topical anesthesia only. Topical anesthesia (eg, Cetacaine, lidocaine) has the advantages of requiring less time for the overall procedure, eliminating the risk of sedation, and decreasing the cost of the procedure by reducing or eliminating recovery time and nursing staff. The disadvantages are patient discomfort and problems in performing the procedure on a patient who may not be still. With the cost-saving trends in medicine, EGD without sedation will likely become more commonplace in the United States. With the introduction of smaller caliber endoscopes that can be passed through the nose, EGD without sedation may be more acceptable to patients.
• When conscious sedation is being administered, the patient must be monitored throughout the procedure. Pulse oximetry, heart rate, and blood pressure are commonly monitored.
• Electrocardiographic monitoring is recommended in patients with cardiopulmonary disease, in elderly patients, and during a prolonged procedure.

Pharmacology of commonly used sedatives, analgesics, and reversal agents

• Benzodiazepines

  • Midazolam (Versed) is a sedative/hypnotic commonly used for sedation in endoscopic procedures. The peak effect of midazolam is 3-5 minutes, with a duration of action of 1-3 hours. Some of the major adverse effects include respiratory depression, hypotension, and paradoxical agitation. The typical starting dose is 0.5-2 mg IV, which can be titrated to achieve a desirable level of sedation (usually in 1-mg increments). Lower doses of midazolam should be administered to elderly patients with cardiopulmonary problems to avoid serious complications.
  • Diazepam (Valium) may be used instead of midazolam for sedation during endoscopic procedures, but many centers prefer midazolam (over diazepam) because of its amnestic effect and reduced tendency to cause phlebitis.
• Opioids

  • Meperidine (Demerol) is a narcotic analgesic that has mild sedative properties, slow onset of action, long duration, and long recovery time. When coadministered with benzodiazepines, potential complications include respiratory depression and sedation. The peak effect of meperidine is approximately 10 minutes, with a duration of action of 2-3 hours. Adverse effects include respiratory depression, hypotension, nausea, and vomiting. The typical starting dose is 15-50 mg IV, with subsequent doses not to exceed 25 mg/dose.
  • Fentanyl (Sublimaze) is a mildly sedative narcotic analgesic that has a rapid onset of action and short recovery time. In many endoscopy centers, fentanyl is the preferred agent for outpatient endoscopic procedures. The peak effect is 5-8 minutes, and the duration of action is 1-3 hours. One of the major adverse effects is respiratory depression. The typical starting dose is 0.03-0.1 mg IV, with subsequent doses of 0.02-0.05 mg/dose.
• Reversal agents

  • Flumazenil (Romazicon) is typically used for reversal of benzodiazepine-induced sedation and respiratory depression. Flumazenil has a peak effect of 3-5 minutes and a duration of action of 1-2 hours. Potential adverse effects include resedation and seizures. The typical dose is 0.2-0.5 mg IV for reversal of sedation (up to 1 mg total) and 1-3 mg IV for benzodiazepine overdose.
  • Naloxone (Narcan) reverses opioid-induced analgesia, CNS effects, and respiratory depression. Naloxone has a peak effect of 1-2 minutes and a duration of action of 1-3 hours. Adverse effects include pain, agitation, nausea, vomiting, arrhythmias, sudden death, pulmonary edema, and withdrawal syndrome in patients with opioid abuse. The typical dose is 0.04 mg IV for reversal of analgesia/sedation and 0.4 mg for narcotic overdose and respiratory arrest.

• Endoscopes are available from several different manufacturers (eg, Olympus, Pentax, Fujinon). The conventional endoscope consists of an umbilical cord, control head (wheels for up/down and left/right, air/water button, and suction button), insertion tube of 100 cm length and 8-11 mm external diameter, and bending section at the tip (which allows up to 180° deflection for retroflexion of the endoscope). The endoscope contains a lumen for insufflation of air and water, a working channel of 2-3 mm diameter (larger channel diameter for therapeutic endoscopes) used for suctioning and passage of instruments, control wires for moving the tip of the endoscope, and the imaging system that is either fiberoptic (rare) or video (widely available). The endoscope, light source, and image source (either video monitor or direct-view through the eyepiece) are essential equipment. Images and video can be recorded and printed depending on the equipment used.
• Flexible ultrathin fiberoptic and video endoscopes that can be used without sedation are also available for EGD. These endoscopes are inserted transnasally or perorally and have a working length of 925-1050 mm, an external diameter of 5.3-6 mm, and a working channel diameter of 2 mm.
• Multiple instruments can be introduced through the working channel of the endoscope. These instruments include biopsy forceps, snares, sclerotherapy needles, heater probes, electrocautery probes, balloon-dilation devices, nets, and baskets. Guidewires can be placed, and, when the endoscope is withdrawn, wire-guided bougie dilators can be passed. Devices can also be placed onto the end of the endoscope for banding of esophageal varices and endoscopic mucosal resection.
• Some of the newer endoscopes provide high resolution and magnifying endoscopy and are used for the evaluation of certain upper gastrointestinal diseases. The upper endoscope is also used to guide endoscopic treatment of gastroesophageal reflux disease (GERD), such as with the Bard EndoCinch endoscopic suturing device and the NDO full-thickness plicator.
• One of the recent advances in video endoscopy is narrow band imaging (NBI). NBI uses optical filters and high relative intensity of blue light for imaging and characterization of mucosal morphology, such as mucosal and superficial vascular patterns. NBI has been studied in patients with Barrett esophagus, early gastric tumors, and colorectal lesions and has had promising results.

• The patient is usually placed in the left lateral position for this procedure.

Patient Preparation

Patient assessment

• Perform a complete history and perform a physical examination to determine whether esophagogastroduodenoscopy (EGD) is appropriate. Document findings in the patient's medical record. Direct special attention to certain illnesses that might bear a direct effect on endoscopy, such as cardiovascular and pulmonary diseases. Obtain a history of drug allergies and previous abdominal surgeries.
• Preprocedure testing in selected cases might include, but is not limited to, a complete blood cell count, blood crossmatching, coagulation studies, a chemistry panel, urinalysis, pregnancy testing, electrocardiogram, and chest radiographs. No data support routine laboratory testing prior to elective outpatient endoscopy. Preprocedure tests should be individualized and based on information obtained from the patient's history and physical examination and the indication for the procedure.

Informed consent

• Obtaining informed consent prior to each endoscopic procedure is extremely important and is the responsibility of the endoscopist.^[2]
• Explain the indications, nature, and relevant details of the procedure to the patient. Risks, benefits, alternatives, and complications should also be presented to the patient.
• The consent form should be signed and dated by the patient and endoscopist and must be witnessed by other personnel and placed in the patient record.

Antibiotic prophylaxis

• Transient bacteremia may occur during most endoscopic procedures, but the risk of infectious complications (including endocarditis) is low. Antibiotic prophylaxis is clearly recommended when patients with an underlying high-risk condition for infectious complications (eg, prosthetic heart valve, history of endocarditis) undergo a high-risk endoscopic procedure, such as stricture dilation, sclerotherapy of varices, and ERCP, in the presence of an obstructed biliary tree. All patients undergoing percutaneous endoscopic gastrostomy placement should receive antibiotic prophylaxis against soft tissue infections; the regimen usually includes cefazolin (1 g IV).
• The patient's condition and the nature of the procedure should be reviewed carefully, and the decision to administer antibiotic prophylaxis is individualized. An acceptable prophylaxis regimen is parenteral ampicillin at 2 g and gentamicin at 1.5 mg/kg (up to 80 mg) 30 minutes prior to the procedure. Vancomycin (1 g IV) is substituted for penicillin in patients who are allergic to penicillin.
• Specific recommendations for antibiotic prophylaxis based on the type of the endoscopic procedure that is being contemplated and the underlying patient condition are available from the American Society for Gastrointestinal Endoscopy (ASGE).

Procedure

• The patient is usually placed in the left lateral position.
• Administer topical and/or intravenous sedation to minimize gagging and to facilitate the procedure.
• Place a bite block to prevent damage to the endoscope and to ease its passage through the mouth.
• Under direct vision, pass the endoscope through the pharynx, esophagus, and stomach and into the duodenum, with careful inspection upon both insertion and slow withdrawal. Insufflate air to distend the lumen to aid in viewing. Liquid and particulate matter can be aspirated through the suction channel. See the videos below.

  Esophagastroduodenoscopy. Video courtesy of George Y Wu, MD, PhD.

  This video shows the insertion of the endoscope over the mouth, into the oropharynx. The vocal cords, epiglottis, and piriformis sinuses are seen, and the scope is advanced into the right piriformis sinus and behind the epiglottis and into the esophagus. This is a normal esophageal intubation when performing esophagogastroduodenoscopy. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.
• The procedure and findings can be documented with pictures or a video system. Biopsy specimens can be obtained by passing forceps and taking small mucosal samples for histology studies. See videos below.

  This video, captured via esophagogastroduodenoscopy, shows biopsy samples being obtained from the duodenum. The duodenal folds show some "scalloping," and biopsies are obtained to rule out celiac sprue. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured via esophagogastroduodenoscopy (EGD), depicts the obtaining of biopsies of the duodenum. This is often performed during EGD to rule out certain diseases. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured via esophagogastroduodenoscopy, shows an abnormal polyp within the stomach. It is then biopsied in order to obtain a pathologic diagnosis and to rule out malignancy. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured via esophagogastroduodenoscopy, shows erythema of antrum of the stomach consistent with gastritis. Biopsies are obtained to rule out Helicobacter pylori infection. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.
• Numerous therapeutic procedures can be performed during the endoscopy (see videos below for examples). The procedure may last from 5-30 minutes or longer, depending on which diagnostic or therapeutic maneuvers are used.

  This video, captured via esophagogastroduodenoscopy, shows the treatment of a bleeding duodenal ulcer by deployment of an Endoclip. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured via esophagogastroduodenoscopy, shows dilation of a duodenal stricture. In this case, the patient developed an NSAIDS-related stricture. He underwent balloon dilation to relieve symptoms of nausea, vomiting, weight loss, and early satiety. The stricture had been biopsied previously to rule out malignancy. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured via esophagogastroduodenoscopy, depicts treatment of an arteriovenous malformation (AVM) in the small intestine using argon plasma coagulation (APC). AVMs are a common cause of gastrointestinal bleeding. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured via esophagogastroduodenoscopy, shows the treatment of a duodenal ulcer with injection of epinephrine into the ulcer. The mucosa is friable and bleeds easily when manipulated. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured via esophagogastroduodenoscopy, shows the use of the HALO 90 device in order to perform radiofrequency ablation in a patient with Barrett esophagus. Barrett esophagus increases the risk of developing esophageal cancer. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.
• The videos below depict normal EGD findings.

  This video shows a normal esophagus via esophagogastroduodenoscopy. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured with esophagogastroduodenoscopy, shows a normal Z line, which is another name for the esophageal gastric (EG) junction. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.
• The videos below depict various abnormal EGD findings.

  This video, captured via esophagogastroduodenoscopy, shows classic "scalloping" of the duodenal folds, a finding seen in celiac sprue. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured via esophagogastroduodenoscopy, depicts erosive gastritis. The antrum of the stomach is erythematous, and some erosions are noted, but no obvious ulcers. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured via esophagogastroduodenoscopy, shows erosive duodenitis, shallow mucosal erosions within the bulb of the duodenum. This can be caused by NSAIDS or Helicobacter pylori infection, in addition to other etiologies. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured via esophagogastroduodenoscopy, shows portal hypertensive gastropathy (PHG). These are changes to the stomach mucosa caused by advanced liver disease. The mucosa has a "snake skin" appearance. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured via esophagogastroduodenoscopy, shows a moderate to severe case of portal hypertensive gastropathy (PHG). These are changes to the stomach mucosa caused by advanced liver disease. The mucosa has a "snake skin" appearance. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video shows "trachealization" of the esophagus, the finding of rings similar to those in the trachea. This is commonly seen in eosinophilic esophagitis. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video shows inflammation and erosion at the distal esophagus, erosive esophagitis. The bleeding is likely secondary to a biopsy that had been performed. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video shows severe distal reflux esophagitis via esophagogastroduodenoscopy. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.

  This video, captured with esophagogastroduodenoscopy, shows an esophageal varix with a nipple, which is a sign of recent bleeding. Video courtesy of Dawn Sears, MD, and Dan C. Cohen, MD, Division of Gastroenterology, Scott & White Healthcare.
• After completion of a procedure performed under conscious sedation, transfer the patient to a recovery room for further monitoring by an endoscopy nurse.
• Once alert and mobile (after approximately 1 h), allow the patient to leave the recovery room with an escort. Give the patient postprocedure instructions (eg, diet, activity) and advise him or her to observe for signs and symptoms of GI bleeding, fever, and abdominal pain.
• A follow-up appointment with the primary care physician and/or the endoscopist is usually arranged prior to patient's discharge from the endoscopy unit.

• The major complications of EGD are bleeding, infection, perforation,^[3] and cardiopulmonary problems. Cardiopulmonary events make up 50% of all major complications; such events are usually caused by the medications used for conscious sedation.^[4]
• Approximately 1 complication occurs for every 1000 EGD procedure.^[4] The mortality rate is approximately 0.5-3 deaths for every 10,000 procedures.^[4]

Recent studies

• Transnasal esophagogastroduodenoscopy (TN-EGD) has certain limitations in bending, which can make approaching certain gastric regions difficult. Rhee et al evaluated whether the quality and quantity of 2 directional TN-EGD biopsied gastric specimens are affected by this limitation.^[5] The quantity of gastric biopsy specimens were assessed according to their diameter and depth (in μm), as well as depth in layers (superficial mucosa, deep mucosa, muscularis mucosa and submucosa). The parameters used to assess specimen quality were degrees of anatomic orientation (good, intermediate and poor), presence of crush artifact (none to minimal, mild and moderate) and overall diagnostic adequacy (adequate, suboptimal and inadequate).^[5]
• Of 289 TN-EGD gastric biopsy specimens, 33 (11.4%) were of poor orientation, 26 (9.0%) revealed the presence of crush, and 37 (12.8%) demonstrated overall diagnostic inadequacy.^[5] In 211 (73.0%) specimens, deep mucosa was present, but only 75 specimens (26.0%) had muscularis mucosa. The posterior aspect of the cardia had the greatest limitations in quantity and quality of specimen results, with the shallowest depth (P = 0.011), poorest orientation (P < 0.001), and poorest diagnostic adequacy (P < 0.001).^[5] The investigators recommended paying special attention to gastric lesions located on the posterior aspect of the cardia when using 2 directional TN-EGD.
• In an interesting 2-part study, Japanese investigators attempted to find a good washing solution to counter the known limitations of the small-caliber water-jet nozzles of TN-EGDs for cleaning lenses.^[6] Komazawa et al compared oolong tea, barley tea, and distilled water as washing solutions for the endoscopic lenses.
• In the first part of the study, the TN-EGD lenses were soiled by lard, followed by washing with 1 of the 3 washing solutions. When the image quality of photographs were judged, lenses washed with oolong tea resulted in a significantly higher image quality of photographs compared with those washed with barley tea or distilled water solutions.^[6]
• In the second part of the study, 982 patients scheduled to undergo TN-EGD were randomly assigned to groups in which the endoscope lens was washed with 1 of the 3 washing solutions. The investigators found that the level of lens cleansing was significantly greater (P < 0.001) and the overall time required for endoscopy was significantly shorter (P < 0.05) in the oolong tea group relative to the other 2 groups.^[6] When the volume of washing solution used for lens cleansing was compared, significantly less was used in the oolong group compared with the distilled water group (P < 0.05).
• On the basis of their findings, Komazawa et al recommended oolong tea rather than water for cleaning TN small-caliber EGD lenses.^[6]

Infection control during gastrointestinal endoscopy

• Despite the large number of endoscopic procedures performed each day, the incidence of infection transmission via endoscopes remains very rare.
• Methods of reprocessing endoscopes include mechanical cleaning, high-level disinfection, rinsing, and drying. Proper and diligent care during reprocessing of endoscopes, with attention to quality control, cannot be overstated for minimizing the risk of spreading infection via endoscopic procedures.

Establishment of gastrointestinal endoscopy areas

• Endoscopy units are specific areas in a hospital (or physician's office) in which all endoscopic procedures are performed.
• For this unit to be functional and effective, the ASGE recommends that certain conditions must be met. These conditions include a properly trained endoscopist and nursing staff, functioning and adequately maintained equipment, an endoscope cleaning area, personnel trained to perform cardiopulmonary resuscitation, and a quality improvement program.

Open access endoscopy

• Open access endoscopy is a system designed to offset the cost of endoscopy in stable patients without significant comorbidities who have clear indications for upper endoscopy.
• The responsibilities of the referring physician are complete understanding of the patient's condition and the accepted indications for endoscopy. If the patient is on anticoagulation or if antibiotic prophylaxis is required, these issues must be addressed via proper communication between the referring physician and the endoscopist.

Training and certification requirements for endoscopists

• The ASGE recommends that training in upper endoscopy include an understanding of indications, limitations, contraindications, alternatives, principles of conscious sedation, and correct interpretation of endoscopic findings. A minimum of 100 upper endoscopic procedures is recommended for trainees to become competent in diagnostic upper endoscopy.
• Therapeutic upper endoscopy requires further training and experience to gain competency. The recommendations of the ASGE for the number of procedures required to gain competency in various therapeutic upper endoscopic procedures are available through the society Web site (see American Society for Gastrointestinal Endoscopy).