Before performing esophagoscopy, all equipment (endoscopic, monitoring, and resuscitative) must be assembled and examined for proper function (Table 14-3). The endoscope should be examined for sterility and external integrity (e.g., the plastic coating must be completely intact without visible fractures). All knobs and buttons should be fit snugly in place and should be tested for proper function, including axial motion, air insufflation, water instillation, and suction. The video monitor should be turned on, the patient data should be entered in the electronic record, and the scope should be balanced for image clarity. The monitor should be placed directly in front of the endoscopist, and the room lights should be dimmed to maximize the quality of the image on the video monitor.
Table 14-3Monitoring and Sedation for Office-Based Endoscopy ||Download (.pdf) Table 14-3Monitoring and Sedation for Office-Based Endoscopy
Confirm patient's NPO status.
Place intravenous line before administering sedatives, and maintain intravenous line until patient has recovered sufficiently to permit safe discharge.
Monitoring baseline pulse, respiratory rate, oxygen saturation, and blood pressure, recorded before administration of any sedatives. Pulse oximetry, cardiac monitoring, automated blood pressure recording, and supplemental oxygen should be employed routinely.
Endoscopy suite must have emergency medications and equipment used for cardiopulmonary resuscitation (including oral suction, defibrillator, ambu bag, laryngoscope, and an emergency airway tray). This equipment must be readily available and checked on a daily basis.
Staff must be appropriately trained in resuscitation. An advanced cardiac life support (ACLS)-certified provider must accompany all sedated patients throughout their stay.
An assistant trained at least in basic cardiac life support (BCLS) should be present during all procedures to monitor the patient.
A registered nurse should monitor the patient in the recovery area.
A formal transport agreement with an acute care facility capable of managing endoscopic complications must be in place and easily executed when necessary.
The patient's status with respect to oral intake is confirmed (NPO for at least 6 hours). Anesthesia has already been selected on the basis of surgeon preference and the goals of the procedure. Standard procedures for anesthesia or conscious sedation are instituted. For general anesthesia, the patient is placed in the supine position on the operating table, induced, and intubated. The conscious patient is placed in left lateral decubitus position, and a mouth guard is placed both to enable passage of the scope into the mouth and to prevent the patient from biting the scope.
Two types of flexible endoscopes are available: videoscopic and those that utilize eye pieces. The standard endoscope is 140 cm long. It has a diameter of 5 to 11 mm and a working port that is 2.8 mm wide. Adult endoscopes typically have two dials that enable four directional control (left and right as well as up and down), whereas pediatric endoscopes have only one dial. In anesthetized adults we typically use a 9- to 12-mm scope, while 5-mm endoscopes are reserved for awake patients and those with tight strictures. All equipment should be examined for proper function prior to the procedure. This includes checking for maneuverability, light, insufflation, suction, and irrigation. Flexible endoscopic equipment is expensive. Proper maintenance (cleaning and storage) of the endoscope, including all its detachable parts, must be maintained to assure long-term function.
After the patient has been inducted with general anesthesia, the endoscope is placed into the oropharynx and esophagus by extending the lower jaw anteriorly and placing the endoscope behind the endotracheal tube (Fig. 14-1). Alternatively, endoscopy can be performed under intravenous conscious sedation or with the patient fully awake. A bite blocker is placed between the teeth to prevent damage to the scope. The conscious patient is positioned on his or her side, usually the left. Monitored sedation is then administered using short-acting intravenous medications, after which the endoscope is carefully introduced. Alternatively, in a cooperative patient, awake endoscopy can be performed with a small scope inserted via the nose or regular endoscope after aerosolized analgesia of the oropharynx. The awake patient can aid the endoscopist by active “swallowing.”
Inserting the endoscope for esophagoscopy.
The endoscope is maneuvered by rotation in the hands of the operator, who at all times should be attempting to center the lumen on the video monitor, which decreases the chance of perforation, and by using insufflation as needed before advancing the endoscope farther along. The scope should be in the unlocked position. The scope should be advanced with minimal force. During endoscopy, the majority of the maneuvering is done by the dominant hand on the scope while the fine tuning is done by the nondominant hand on the dials. Typically, in the anesthetized patient, the scope can be passed directly into the mid-esophagus with the nondominant hand. The mouth and chin are elevated and the scope is gently advanced. If resistance is encountered, the endoscopist should draw back 1 to 2 cm, center the scope, and only then gently advance. After the scope is beyond the first narrowing of the upper esophageal sphincter at the cricopharyngeus, the esophagus is insufflated with air and the mucosa examined as the scope is advanced (Fig. 14-2).
Anatomic regions of esophageal and proximal foregut narrowing. Cricopharyngeus (14 cm in females, 15 cm in males). Carina and aortic arch (24–26 cm). Diaphragmatic constriction in the area of the lower esophageal sphincter (LES; 36–38 cm in females, 38–40 cm in males). Pylorus (small arrow).
A second narrowing occurs in the area of the aortic arch and carina, approximately 24 to 25 cm from the incisors. The final anatomic narrowing occurs at the lower esophageal sphincter (LES), which is about 40 cm from the incisors. The esophageal, gastric, and duodenal mucosae are examined visually for lesions, strictures, webs, ulcers, dilatations, diverticula, and other pathology (Fig. 14-3). The Z-line is identified, and the length is measured (incisors to Z-line) and documented.
Representative pathology. A. Barrett's distal esophagus. B. Retroflex view showing slipped Nissen fundoplication.
The stomach is entered, insufflated, and examined in its entirety. Retroflexion is performed by advancing the scope into the greater curvature and then angling it to achieve maximal retroflexion. The scope is pulled back toward the gastroesophageal junction and turned 360 degrees, providing good visualization of the esophagogastric junction and its relation to the hiatus from within the stomach. The greater and lesser curvatures of the stomach, as well as the antrum and pylorus, are insufflated and examined. The scope is then passed into the second part of the duodenum to exclude the presence of additional pathology and determine how tight the pylorus may be. In our practice, endoscopy routinely includes visualization up to and including the second part of the duodenum. Before withdrawing the scope from the duodenum, air is removed by suction.
Depending on the indication for esophagoscopy, after visual examination, diagnostic procedures such as biopsy using flexible biopsy forceps or therapeutic procedures can be performed. Visual examination of the mucosa is typically performed using white light. Attention is paid to the regularity of the mucosa, in addition to color and presence of nodularity, ulceration, or masses. Newer scopes may have customized features such as a narrow band imaging (NBI) mode that accentuates the microvasculature and can help the endoscopist identify subtle changes. Additional diagnostic endoscopic modalities include life-scope and confocal technologies. Currently, these are not widely used. Biopsy should be performed when suspected pathology is encountered. This can be accomplished with regular or jumbo forceps. Endoscopic mucosal resection (EMR) may provide diagnostic as well as therapeutic benefit (see Chapter 173). In the event of stricture, a guidewire may be inserted to cross the stricture before (if the stricture is very tight) or after the scope has traversed it. The scope is withdrawn, and serial dilations are carried out using Savary dilators. Alternatively, a pneumatic dilator can be placed over the guidewire and the stricture dilated using preset pressure and diameter. Completion endoscopy is then carried out to evaluate the results of the dilation and to rule out procedure-related injury. In cases where stenting is indicated a guidewire can be placed beyond the target lesion, and a stent placed under direct endoscopic vision or using fluoroscopy.