Bronchoscopy and Esophagoscopy Part 2

_Asepsis_.--Strict aseptic technic must be observed in all endoscopic procedures. The operator, first a.s.sistant, and instrument nurse must use the same precautions as to hand sterilization and sterile gowns as would be exercised in any surgical operation. The operator and first a.s.sistant should wear masks and sterile gloves. The patient is instructed to cleanse the mouth thoroughly with the tooth brush and a 20 per cent alcohol mouth wash. Any dental defects should, if time permit, as in a course of repeated treatments, be remedied by the dental surgeon. When placed on the table with neck bare and the shoulders unhampered by clothing, the patient is covered with a sterile sheet and the head is enfolded in a sterile towel. The face is wiped with 70 per cent alcohol.

It is to be remembered that while the patient is relatively immune to the bacteria he himself harbors, the implantation of different strains of perhaps the same type of organisms may prove virulent to him.

Furthermore the transference of lues, tuberculosis, diphtheria, pneumonia, erysipelas and other infective diseases would be inevitable if sterile precautions were not taken.

All of the tubes and forceps are sterilized by boiling. The light-carriers and lamps may be sterilized by immersion in 95 per cent alcohol or by prolonged exposure to formaldehyde gas. Continuous sterilization by keeping them put away in a metal box with formalin pastilles or other source of formaldehyde gas is an ideal method.

Knives and scissors are immersed in 95 per cent alcohol, and the rubber covered conducting cords are wiped with the same solution.

_List of Instruments_.--The following list has been compiled as a convenient basis for equipment, to which such special instruments as may be needed for special cases can be added from time to time. The instruments listed are of the author's design.

1 adult's laryngoscope.

1 child's laryngoscope.

1 infant's diagnostic laryngoscope.

1 anterior commissure laryngoscope.

1 bronchoscope, 4 mm. X 30 cm.

1 bronchoscope, 5 mm. X 30 cm.

1 bronchoscope, 7 mm. X 40 cm.

1 bronchoscope, 9 mm. X 40 cm.

1 esophagoscope, 7 mm. X 45 cm.

1 esophagoscope, 10 mm. X 53 cm.

1 esophagoscope, full lumen, 7 mm. X 45 cm.

1 esophagoscope, full lumen, 9 mm. X 45 cm.

1 esophageal speculum, adult.

1 esophageal speculum, child.

1 forward-grasping forceps, delicate, 40 cm.

1 forward-grasping forceps, regular, 50 cm.

1 forward-grasping forceps, regular, 60 cm.

1 side-grasping forceps, delicate, 40 cm.

1 side-grasping forceps, regular, 50 cm.

1 side-grasping forceps, regular, 60 cm.

1 rotation forceps, delicate, 40 cm.

1 rotation forceps, regular, 50 cm.

1 rotation forceps, regular, 60 cm.

1 laryngeal alligator forceps.

1 laryngeal papilloma forceps.

10 esophageal bougies, Nos. 8 to 17 French (larger sizes to No. 36 may be added).

1 special measuring rule.

6 light sponge carriers.

1 aspirator with double tube for minus and plus pressure.

2 endoscopic aspirating tubes 30 and 50 cm.

1 half curved hook, 60 cm.

1 triple circuit bronchoscopy battery.

6 rubber covered conducting cords for battery.

1 box bronchoscopic sponges, size 4.

1 box bronchoscopic sponges, size 5.

1 box bronchoscopic sponges, size 7.

1 box bronchoscopic sponges, size 10.

1 bite block, 1 adult.

1 bite block, child.

2 dozen extra lamps for lighted instruments.

1 extra light carrier for each instrument.*

4 yards of pipe-cleaning, worsted-covered wire.

[* Messrs. George P. Pilling and Sons who are now making these instruments supply an extra light carrier and 2 extra lamps with each instrument.]

_Care of Instruments_.--The endoscopist must either personally care for his instruments, or have an instrument nurse in his own employ, for if they are intrusted to the general operating room routine he will find that small parts will be lost; blades of forceps bent, broken, or rusted; tubes dinged; drainage ca.n.a.ls choked with blood or secretions which have been coagulated by boiling, and electric attachments rendered unstable or unservicable, by boiling, etc. The tubes should be cleansed by forcing cold water through the drainage ca.n.a.ls with the aspirating syringe, then dried by forcing pipe-cleaning worsted-covered wire through the light and drainage ca.n.a.ls. Gauze on a sponge carrier is used to clean the main ca.n.a.l.

Forceps stylets should be removed from their cannulae, and the cannulae cleansed with cold water, then dried and oiled with the pipe-cleaning material. The stylet should have any rough places smoothed with fine emery cloth and its blades carefully inspected; the parts are then oiled and rea.s.sembled. Nickle plating on the tubes is apt to peel and these scales have sharp, cutting edges which may injure the mucosa. All tubes, therefore, should be unplated. Rough places on the tubes should be smoothed with the finest emery cloth, or, better, on a buffing wheel. The dry cells in the battery should be renewed about every 4 months whether used or not. Lamps, light carriers, and cords, after cleansing, are wiped with 95 per cent alcohol, and the light-carriers with the lamps in place are kept in a continuous sterilization box containing formaldehyde pastilles. It is of the utmost importance that instruments be always put away in perfect order. Not only are cleaning and oiling imperative, but any needed repairs should be attended to at once. Otherwise it will be inevitable that when gotten out in an emergency they will fail. In general surgery, a spoon will serve for a retractor and good work can be done with makeshifts; but in endoscopy, especially in the small, delicate, natural pa.s.sages of children, the handicap of a defective or insufficient armamentarium may make all the difference between a success and a fatal failure.

A bronchoscopic clinic should at all times be in the same state of preparedness for emergency as is everywhere required of a fire-engine house.

[PLATE I--A WORKING SET OF THE AUTHOR'S ENDOSCOPIC TUBES FOR LARYNGOSCOPY, BRONCHOSCOPY, ESOPHAGOSCOPY, AND GASTROSCOPY: A, Adult's laryngoscope; B, child's laryngoscope; C, anterior commissure laryngoscope; D, esophageal speculum, child's size; E, esophageal speculum, adult's size; F, bronchoscope, infant's size, 4 mm. X 30 cm.; G, bronchoscope, child's size, 5 mm. X 30 cm.; H, aspirating bronchoscope for adults, 7 mm. X 40 cm.; I, bronchoscope, adolescent's size, 7 mm. x 40 cm., used also for the deeper bronchi of adults; J, bronchoscope, adult size, g mm. x 40 cm.; K, child's size esophagoscope, 7 mm. X 45 cm.; L, adult's size esophagoscope, full lumen construction, 9 mm. x 45 cm.; M, adult's size gastroscope. C, I, and E are also hypopharyngoscopes. C is an excellent esophageal speculum for children, and a longer model is made for adults.

If the utmost economy must be practised D, E, and M may be omitted.

The balance of the instruments are indispensable if adults and children are to be dealt with. The instruments are made by Charles J.

Pilling & Sons, Philadelphia.]

[52] CHAPTER II--ANATOMY OF LARYNX, TRACHEA, BRONCHI AND ESOPHAGUS, ENDOSCOPICALLY CONSIDERED

The _larynx_ is a cartilaginous box, triangular in cross-section, with the apex of the triangle directed anteriorly. It is readily felt in the neck and is a landmark for the operation of tracheotomy. We are concerned endoscopically with four of its cartilaginous structures: the epiglottis, the two arytenoid cartilages, and the cricoid cartilage. The _epiglottis_, the first landmark in direct laryngoscopy, is a leaf-like projection springing from the anterointernal surface of the larynx and having for its function the directing of the bolus of food into the pyriform sinuses. It does not close the larynx in the trap-door manner formerly taught; a fact easily demonstrated by the simple insertion of the direct laryngoscope and further demonstrated by the absence of dysphagia when the epiglottis is surgically removed, or is destroyed by ulceration.

Closure of the larynx is accomplished by the approximation of the ventricular bands, arytenoids and aryepiglottic folds, the latter having a sphincter-like action, and by the raising and tilting of the larynx. The _arytenoids_ form the upper posterior boundary of the larynx and our particular interest in them is directed toward their motility, for the rotation of the arytenoids at the cricoarytenoid articulations determines the movements of the cords and the production of voice. Approximation of the arytenoids is a part of the mechanism of closure of the larynx.

The _cricoid cartilage_ was regarded by esophagoscopists as the chief obstruction encountered on the introduction of the esophagoscope. As shown by the author, it is the cricopharyngeal fold, and the inconceivably powerful pull of the cricopharyngeal muscle on the cricoid cartilage, that causes the difficulty. The cricoid is pulled so powerfully back against the cervical spine, that it is hard to believe that this muscles is inserted into the median raphe and not into the spine itself (Fig. 68).

The _ventricular bands_ or false vocal cords vicariously phonate in the absence of the true cords, and a.s.sist in the protective function of the larynx. They form the floor of the _ventricles_ of the larynx, which are recesses on either side, between the false and true cords, and contain numerous mucous glands the secretion from which lubricates the cords. The ventricles are not visible by mirror laryngoscopy, but are readily exposed in their depths by lifting the respective ventricular bands with the tip of the laryngoscope. The _vocal cords_, which appear white, flat, and ribbon-like in the mirror, when viewed directly a.s.sume a reddish color, and reveal their true shelf-like formation. In the subglottic area the tissues are vascular, and, in children especially, they are p.r.o.ne to swell when traumatized, a fact which should be always in mind to emphasize the importance of gentleness in bronchoscopy, and furthermore, the necessity of avoiding this region in tracheotomy because of the danger of producing chronic laryngeal stenosis by the reaction of these tissues to the presence of the tracheotomic cannula.

The _trachea_ just below its entrance into the thorax deviates slightly to the right, to allow room for the aorta. At the level of the second costal cartilage, the third in children, it bifurcates into the right and left main bronchi. Posteriorly the bifurcation corresponds to about the fourth or fifth thoracic vertebra, the trachea being elastic, and displaced by various movements. The endoscopic appearance of the trachea is that of a tube flattened on its posterior wall. In two locations it normally often a.s.sumes a more or less oval outline; in the cervical region, due to pressure of the thyroid gland; and in the intrathoracic portion just above the bifurcation where it is crossed by the aorta. This latter flattening is rhythmically increased with each pulsation. Under pathological conditions, the tracheal outline may be variously altered, even to obliteration of the lumen. The mucosa of the trachea and bronchi is moist and glistening, whitish in circular ridges corresponding to the cartilaginous rings, and reddish in the intervening grooves.

The right bronchus is shorter, wider, and more nearly vertical than its fellow of the opposite side, and is practically the continuation of the trachea, while the left bronchus might be considered as a branch. The deviation of the right main bronchus is about 25 degrees, and its length unbranched in the adult is about 2.5 cm. The deviation of the left main bronchus is about 75 degrees and its adult length is about 5 cm. The right bronchus considered as a stem, may be said to give off three branches, the epiarterial, upper- or superior-lobe bronchus; the middle-lobe bronchus; and the continuation downward, called the lower- or inferior-lobe bronchus, which gives off dorsal, ventral and lateral branches. The left main bronchus gives off first the upper-or superior-lobe bronchus, the continuation being the lower-or inferior-lobe bronchus, consisting of a stem with dorsal, ventral and lateral branches.

[FIG. 44.--Tracheo-bronchial tree. LM, Left main bronchus; SL, superior lobe bronchus; ML, middle lobe bronchus; IL, inferior lobe bronchus.]

The septum between the right and left main bronchi, termed the carina, is situated to the left of the midtracheal line. It is recognized endoscopically as a short, shining ridge running sagitally, or, as the patient lies in the rec.u.mbent position, we speak of it as being vertical. On either side are seen the openings of the right and left main bronchi. In Fig. 44, it will be seen that the lower border of the carina is on a level with the upper portion of the orifice of the right superior-lobe bronchus; with the carina as a landmark and by displacing with the bronchoscope the lateral wall of the right main bronchus, a second, smaller, vertical spur appears, and a view of the orifice of the right upper-lobe bronchus is obtained, though a lumen image cannot be presented. On pa.s.sing down the right stem bronchus (patient rec.u.mbent) a horizontal part.i.tion or spur is found with the lumen of the middle-lobe bronchus extending toward the ventral surface of the body. All below this opening of the right middle-lobe bronchus const.i.tutes the lower-lobe bronchus and its branches.

[FIG. 45.--Bronchoscopic views.

S; Superior lobe bronchus; SL, superior lobe bronchus; I, inferior lobe bronchus; M, middle lobe bronchus.]

[56] Coming back to the carina and pa.s.sing down the left bronchus, the relatively great distance from the carina to the upper-lobe bronchus is noted. The spur dividing the orifices of the left upper- and lower-lobe bronchi is oblique in direction, and it is possible to see more of the lumen of the left upper-lobe bronchus than of its h.o.m.ologue on the right. Below this are seen the lower-lobe bronchus and its divisions (Fig. 45).

_Dimensions of the Trachea and Bronchi_.--It will be noted that the bronchi divide monopodially, not dichotomously. While the lumina of the individual bronchi diminish as the bronchi divide, the sum of the areas shows a progressive increase in total tubular area of cross-section. Thus, the sum of the areas of cross-section of the two main bronchi, right and left, is greater than the area of cross section of the trachea. This follows the well known dynamic law. The relative increase in surface as the tubes branch and diminish in size increases the friction of the pa.s.sing air, so that an actual increase in area of cross section is necessary, to avoid increasing resistance to the pa.s.sage of air.

The cadaveric dimensions of the tracheobronchial tree may be epitomized approximately as follows: Adult Male Female Child Infant Diameter trachea, 14 X 20 12 X 16 8 X 10 6 X 7 Length trachea, cm. 12.0 10.0 6.0 4.0 Length right bronchus 2.5 2.5 2.0 1.5 Length left bronchus 5.0 5.0 3.0 2.5 Length upper teeth to trachea 15.0 23.0 10.0 9.0 Length total to secondary bronchus 32.0 28.0 19.0 15.0

In considering the foregoing table it is to be remembered that in life muscle tonus varies the lumen and on the whole renders it smaller. In the selection of tubes it must be remembered that the full diameter of the trachea is not available on account of the glottic aperture which in the adult is a triangle measuring approximately 12 X 22 X 22 mm.

and permitting the pa.s.sage of a tube not over 10 mm. in diameter without risk of injury. Furthermore a tube which filled the trachea would be too large to enter either main bronchus.

The normal movements of the trachea and bronchi are respiratory, pulsatory, bechic, and deglut.i.tory. The two former are rhythmic while the two latter are intermittently noted during bronchoscopy. It is readily observed that the bronchi elongate and expand during inspiration while during expiration they shorten and contract. The bronchoscopist must learn to work in spite of the fact that the bronchi dilate, contract, elongate, shorten, kink, and are dinged and pushed this way and that. It is this resiliency and movability that make bronchoscopy possible. The inspiratory enlargement of lumen opens up the forceps s.p.a.ces, and the facile bronchoscopist avails himself of the opportunity to seize the foreign body.

THE ESOPHAGUS

A few of the anatomical details must be kept especially in mind when it is desired to introduce straight and rigid instruments down the lumen of the gullet. First and most important is the fact that the esophageal walls are exceedingly thin and delicate and require the most careful manipulation. Because of this delicacy of the walls and because the esophagus, being a constant pa.s.sageway for bacteria from the mouth to the stomach, is never sterile, surgical procedures are a.s.sociated with infective risks. For some other and not fully understood reason, the esophagus is, surgically speaking, one of the most intolerant of all human viscera. The anterior wall of the esophagus is in a part of its course, in close relation to the posterior wall of the trachea, and this portion is called the party wall. It is this party wall that contains the lymph drainage system of the posterior portion of the larynx, and it is largely by this route that posteriorly located malignant laryngeal neoplasms early metastasize to the mediastinum.