[FIG. 64.—At A is shown an incorrect manner of holding the bronchoscope. The grasp is too rigid and the position of the hand is awkward. B, Correct manner, the collar being held lightly between the finger and the thumb The thumb must not occlude the tube mouth.]
The Fulcrum of the Bronchoscopic Lever is at the Upper Thoracic Aperture; Never at the Larynx.—Disregard of this rule will cause subglottic edema and will limit the lateral motion of the tip of the bronchoscope. It is the function of the assistant to make the head and neck follow the direction of the proximal end of the bronchoscope and thus avoid any pressure on the larynx (see Peroral Endoscopy, Fig. 135, p. 164).
In passing down the trachea the following two rules must be kept in mind: 1. Before attempting to enter either main bronchus the carina must be identified. 2. Before entering either main bronchus the orifices of both should be identified and inspected. The carina is identified as a sharp vertical spur (recumbent patient) at the distal end of the trachea, on either side of which are the openings of the main bronchi. As the carina is situated to the left of the midline of the trachea, the lip of the bronchoscope should be turned toward the left, and slight lateral pressure should be made on the left tracheal wall while the head of the patient is held slightly to the right. This will expose the left bronchial orifice and carina.
Entering the Bronchi.—The lip of the bronchoscope should be turned in the direction of the bronchus to be explored, and the axis of the bronchoscope should be made to correspond as nearly as possible to the axis of this bronchus. The position of the lip is designated by the direction taken by the handle. Upon entering the right bronchus, the handle of the bronchoscope is turned horizontally to the right, and at the same time the assistant deflects the head to the left.
The right upper-lobe bronchus is recognized by its vertical spur; the orifice is exposed by displacing the right lateral wall of the right main bronchus at the level of the carina. Usually this orifice will be thus brought into view. If not the bronchoscope may be advanced downward 1 or 2 cm., carefully to avoid overriding. This branch is sometimes found coming off the trachea itself, and even if it does not, the overriding of the orifice is certain if the right bronchus is entered before search is made for the upper-lobe-bronchial orifice. The head must be moved strongly to the left in order to view the orifice. A lumen image of the right upper-lobe bronchus is not obtainable because of the sharp angles at which it is given off. The left upper-lobe bronchus is entered by keeping the handle of the bronchoscope (and consequently the lip) to the left, and, by keeping the head of the patient strongly to the right as the bronchoscopist goes down the left main bronchus. This causes the lip of the bronchoscope to bear strongly on the left wall of the left main bronchus, consequently the left upper-lobe-bronchial orifice will not be overridden. The spur separating the upper-lobe-bronchial orifice from the stem bronchus is at an angle approximately from two to eight o'clock, as usually seen in the recumbent patient. A lumen image of a descending branch of the upper-lobe bronchus is often obtained, if the patient's head be borne strongly enough to the right.
[FIG. 65.—Schema illustrating the entering of the anteriorly branching middle lobe bronchus. T, Trachea; B, orifice of left main bronchus at bifurcation of trachea. The bronchoscope, S, is in the right main bronchus, pointing in the direction of the right inferior lobe bronchus, I. In order to cause the lip to enter the middle lobe bronchus, M, it is necessary to drop the head so that the bronchoscope in the trachea TT, will point properly to enable the lip of the tube mouth to enter the middle lobe bronchus, as it is seen to have done at ML.]
Branches of the stem bronchus in either lung are exposed, or their respective lumina presented, by manipulation of the lip of the bronchoscope, with movement of the head in the required direction. Posterior branches require the head quite high. A large one in the left stem just below the left upper-lobe bronchus is often invaded by foreign bodies. Anterior branches require lowering the head. The middle-lobe bronchus is the largest of all anterior branches. Its almost horizontal spur is brought into view by directing the lip of the bronchoscope upward, and dropping the head of the patient until the lip bears strongly on the anterior wall of the right bronchus (see Fig. 65).
[106] CHAPTER X—INTRODUCTION OF THE ESOPHAGOSCOPE
The esophagoscope is to be passed only with ocular guidance, never blindly with a mandrin or obturator, as was done before the bevel-ended esophagoscope was developed. Blind introduction of the esophagoscope is equally as dangerous as blind bouginage. It is almost certain to cause over-riding of foreign bodies and disease. In either condition perforation of the esophagus is possible by pushing a sharp foreign body through the normal wall or by penetrating a wall weakened by disease. Landmarks must be identified as reached, in order to know the locality reached. The secretions present form sufficient lubrication for the instrument. A clear conception of the endoscopic anatomy, the narrowings, direction, and changes of direction of the axis of the esophagus, are necessary. The services of a trained assistant to place the head in the proper sequential "high-low" positions are indispensible (Figs. 52 and 70). Introduction may be divided into four stages. 1. Entering the right pyriform sinus. 2. Passing the cricopharyngeus. 3. Passing through the thoracic esophagus. 4. Passing through the hiatus.
The patient is placed in the Boyce position as described in Chapter VI. As previously stated, the esophagus in its upper portion follows the curves of the cervical and dorsal spine. It is necessary, therefore, to bring the cervical spine into a straight line with the upper portion of the dorsal spine and this is accomplished by elevation of the head—the "high" position (Figs. 66-71).