Stage 3. Passing Through the Thoracic Esophagus.—The thoracic esophagus will be seen to expand during inspiration and contract during expiration, due to the change in thoracic pressure. The esophagoscope usually glides easily through the thoracic esophagus if the patient's position is correct. After the levels of the aorta and left bronchus are passed the lumen of the esophagus seems to have a tendency to disappear anteriorly. The lumen must be kept in axial view and the head lowered as required for this purpose.
Stage 4. Passing Through the Hiatus Esophageus.—When the head is dropped, it must at the same time be moved horizontally to the right in order that the axis of the tube shall correspond to the axis of the lower third of the esophagus, which deviates to the left and turns anteriorly. The head and shoulders at this time will be found to be considerably below the plane of the table top (Fig. 71). The hiatal constriction may assume the form of a slit or rosette. If the rosette or slit cannot be promptly found, as may be the case in various degrees of diffuse dilatation, the tube mouth must be shifted farther to the left and anteriorly. When the tube mouth is centered over the hiatal constriction moderately firm pressure continued for a short time will cause it to yield. Then the tube, maintaining this same direction will, without further trouble glide into and through the abdominal esophagus. The cardia will not be noticed as a constriction, but its appearance will be announced by the rolling in of reddish gastric mucosal folds, and by a gush of fluid from the stomach.
[FIG. 70.—Schematic illustration of the author's "high-low" method of esophagoscopy, fourth stage. Passing the hiatus. The head is dropped from the position of the 1st and 2nd stages, CL, to the position T, and at the same time the head and shoulders are moved to the right (without rotation) which gives the necessary direction for passing the hiatus.]
[FIG. 71.—Esophagoscopy by the author's "high-low" method. Stage 4. Passing the hiatus The patient's vertex is about 5 cm. below the top of the table.]
Normal esophageal mucosa under proper illumination is glistening and of a yellowish or bluish pink. The folds are soft and velvety, rendering infiltration quickly noticeable. The cricoid cartilage shows white through the mucosa. The gastric mucosa is a darker pink than that of the esophagus and when actively secreting, its color in some cases tends toward crimson.
Secretions in the esophagus are readily aspirated through the drainage canal by a negative pressure pump. Food particles are best removed by "sponge pumping," or with forceps. Should the drainage canal become obstructed positive pressure from the pump will clear the canal.
Difficulties of Esophagoscopy.—The beginner may find the esophagoscope seemingly rigidly fixed, so that it can be neither introduced nor withdrawn. This usually results from a wedging of the tube in the dental angle, and is overcome by a wider opening of the jaws, or perhaps by easing up of the bite block, but most often by correcting the position of the patient's head. If the beginner cannot start the tube into the pyriform sinus in an adult, it is a good plan to expose the arytenoid eminence with the laryngoscope and then to insert the 7 mm. esophagoscope into the right pyriform sinus by direct vision. Passing the cricopharyngeal and hiatal spasmodically contracted narrowings will prove the most trying part of esophagoscopy; but with the head properly held, and the tube properly placed and directed, patient waiting for relaxation of the spasm with gentle continuous pressure will usually expose the lumen ahead. In his first few esophagoscopies the novice had best use general anesthesia to avoid these difficulties and to accustom himself to the esophageal image. In the first favorable subject—an emaciated individual with no teeth—esophagoscopy without anesthesia should be tried.
In cases of kyphosis it is a mistake to try to straighten the spine. The head should be held correspondingly higher at the beginning, and should be very slowly and cautiously lowered.
Once inserted, the esophagoscope should not be removed until the completion of the procedure, unless respiratory arrest demands it. Occasionally in stenotic conditions the light may become covered by the upwelling of a flood of fluid, and it will be thought the light has gone out. As soon as the fluid has been aspirated the light will be found burning as brightly as before. If a lamp should fail it is unnecessary to remove the tube, as the light carrier and light can be withdrawn and quickly adjusted. A complete instrument equipment with proper selection of instruments for the particular case are necessary for smooth working.
Ballooning Esophagoscopy.—By inserting the window plug shown in Fig. 6 the esophagus may be inflated and studied in the distended state. The folds are thus smoothed out and constrictions rendered more marked. Ether anesthesia is advocated by Mosher. The danger of respiratory arrest from pressure, should the patient be dyspneic, is always present unless the anesthetic be given by the intratracheal method. If necessary to use forceps the window cap is removed. If the perforated rubber diaphragm cap be substituted the esophagus can be reballooned, but work is no longer ocularly guided. The fluoroscope may be used but is so misleading as to render perforation and false passage likely.