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Laryngoscopy
Laryngoscopy JOSEPH L. GOLDMAN, M.D., F.A.C.S.* HARRY TALBOT, M.D.**
LARYNGOSCOPY presents the means to inspect and treat the larynx which is comparatively more accessible for examination and application of therapy than most organs because of its location in the upper respiratory tract. It is this accessibility which permits visualization of the larynx by two different methods, indirect or mirror laryngoscopy and direct laryngoscopy. While both methods offer the opportunity for examination and instrumentation, each has certain inherent advantages. At times both methods must be used to provide the best results for examiner and patient.
INDIRECT LARYNGOSCOPY
Indirect or mirror laryngology can be accomplished with ease, and the gag reflex which may offer difficulty can be controlled. Interns and residents in medicine and surgery should be trained in the use of the laryngeal mirror. Routine laryngeal examinations performed by the internist will uncover lesions in the larynx at an early stage as he is usually the first clinician to see this patient. At least, deviations from the normal, if not specific lesions, will be detected in the early phases of the disease, and thus the help of the laryngologist can be sought at an earlier stage. In performing mirror laryngoscopy, a clear, bright light, either reflected or from a headlight, is essential. The examiner and the patient should be seated opposite each other, the patient leaning slightly forward with the tongue protruded. The tip of the tongue is covered with gauze and is held out by the thumb and middle finger while the index finger holds away the upper lip. The tongue should not be pressed too firmly or pulled too hard lest this cause pain. In particular, if there are sharp or jagged lower teeth, the under surface of the tongue should be protected from any trauma. Any painful maneuver results in the loss of the pa* Head of Department of Otolaryngology, The Mount Sinai Hospital; Clinical Professor of Otolaryngology, College of Physicians and Surgeons, Columbia University, New
York, N. Y.
** Senior Resident, Department of Otolaryngology, 1301
The Mount Sinai Hospital.
1302
Joseph L. Goldman, Harry Talbot
tient's cooperation, the important prerequisite for easy and adequate visualization of the larynx. After the patient is instructed to breathe steadily throughout the procedure, the previously warmed mirror (to prevent condensation) is introduced into the back of the mouth so as to lie against the base of the uvula and soft palate. To be certain that the mirror is not hot enough to bum the patient, it should be tested either on the back of the hand, the thenar eminence, or cheek of the examiner. Care should be exercised that the mirror does not touch the dorsum of the tongue as this may induce the gag reflex in most patients. The tongue of some persons seem to be insensitive to such manipulations. Finally, the examiner gently pushes back the uvula and the soft palate to the posterior pharyngeal wall. By tilting the mirror to the proper angle, which can be correctly judged only after practice and experience, the structures from the base of the tongue to even the upper tracheal rings can be brought into view. A more complete view of the anterior portions of the vocal cords and of the anterior commissure is obtained through the phonating mechanism of raising the epiglottis by having the patient attempt to say "e" or "a". If the gag reflex is marked, visualization may be impossible without anesthetizing the pharynx and occasionally also the larynx. Sometimes the epiglottis obstructs a clear view of the larynx. In such cases, after satisfactory local anesthesia, the patient is instructed to hold the tongue forward with the right hand, the mirror is introduced with the left hand in the manner previously described, and with the other hand, a suitably curved epiglottis retractor (for this the curved tip of the standard laryngeal syringe is useful) is introduced over the base of the tongue under indirect vision to the posterior surface of the epiglottis. The latter is then gently pulled forward and slightly upward in order to expose the larynx more fully. The indirect method of laryngeal examination offers the opportunity for conclusive diagnostic evaluation by inspection in most cases. Although the image of the larynx is inverted and foreshortened, depending on the angle of the mirror in the mouth, an accurate appraisal of the larynx can be obtained by the experienced examiner. Also, surgical procedures of considerable variety can be executed by this method by using laryngeal punch tips and curved knives, but skill acquired by long and diligent training is necessary to master the technique involved. DIRECT LARYNGOSCOPY
Instrument. The variations in designs of direct laryngoscopes have been dependent on different sources of illumination and fixity of the handle. The earliest instruments ~arried the lighting proximally attached to the handle (Kirstein, Yankauerl [Fig. 355], Bruening2 [Fig. 356]). A frontal headlight also could serve the purpose of proximal illumination. The men who relied on proximal illumination similarly favored the detachable
Laryngoscopy
1303
Fig. 355. The Yankauer speculum, with proximal lighting. (Courtesy of W. F. Prior Company, Inc.)
type of handle into which fitted a rectangular metal bar (Bruening, Yankauer). The most commonly used laryngoscope is the tube-handle type as exemplified by the Jackson instrument (Fig. 357) or one of its modifications (Holinger, Andrews). It is the shortest of tubes used in endoscopic procedures. It relies on distal illumination, and, as the name implies, it consists of a tube with a permanently attached handle. The sizes vary from infants' to adults'. Essentially the laryngoscope is a rigid metal
Fig. 356. Bruening's handle with proximal lighting and wire cord attachment.
1304
Joseph L. Goldman, Harry Talbot
Fig. 357. A, Jackson's laryngoscope, adult size. B, Jackson's laryngoscope, infant size.
tube between 4 and 7 inches long, at the distal end of which is a lipped blade or speculum. The Negus3laryngoscope (Fig. 358) differs mainly from this in that it offers a dual lighting system. The beams begin about one-quarter of the way down the tube and cross each other at the distal end where the greatest concentration of light is produced. Position. Laryngoscopy is performed, as a rule, with the patient in the dorsal recumbent position. The position of the head often determines the ease or difficulty with which the examination can be performed. The head, neck and shoulders beyond the spines of the scapulae should project over the end of the table. The head is supported in such a way that it can be raised and extended at the atlanto-occipital joint. This position is best maintained by an assistant, although some form of special head rest fixed to the table is used occasionally. The raising of the shoulders during the procedure should be avoided. Examination. The Jackson laryngoscope is introduced with the left hand while the Bruening handle is held with the right. Care must be exercised to protect the upper lip and teeth from trauma. At no time should the teeth be used as a fulcrum. It is usual to pass the laryngoscope over the right side of the tongue towards the middle of the base of the tongue with the object of bringing the epiglottis into view. It is sometimes necessary to elevate the base of the tongue to accomplish this and it may be helpful to pull the tongue forward. The descent of the laryngoscope is then carried directly forward until the posterior surface"'of the epiglottis is engaged. At this point exposure of the larynx depends on skill rather than strength and is accomplished by lifting the spatular end of the laryngoscope upward and forward by a tilting motion of the wrist.
Laryngoscopy
1305
Fig. 358. The Negus twin-illuminated laryngoscope.
The larynx is kept in view by maintaining the structures anterior to the epiglottis in suspension. Maneuvers may be required to expose the ventricles and a special anterior commissure laryngoscope (Jackson) to examine the subglottic area. Suspension Laryngoscopy. Suspension laryngoscopy is an elaboration of the direct procedure and was designed to leave both hands of the surgeon free for operative intervention. The working principle of the apparatus depends on the suspension of a tongue blade, attached to a mouth gag, by a crane arrangement fixed to the operating table. The tongue blade exposes the larynx. The Lynch modification of the original Killian instrument is the one that is generally used for this purpose at present. In recent years the suspension of the larynx by self-retaining supports which rest on the chest have been used with increasing popularity. There have been a number of instruments of this type since Roberts and Forman4 reintroduced this method. King 5 devised an instrument which he called a "stabilizer" for use with the Jackson laryngoscope and Somers 6 described another type of self-retaining attachment for the laryngoscope. This was followed by the Andrews chest support, and finally in 1954, Lewy7 presented his instrument which combined many of the best features of the self-retaining chest supports which had been in use previously. PREPARATION OF PATIENT FOR OPERATIVE PROCEDURES
This phase of the discussion is concerned with direct laryngoscopy as regards both examination and operative procedures and with the indirect
1308
Joseph L. Goldman, Harry Talbot
method when operative intervention is contemplated, and deserves consideration because these procedures are usually performed under local anesthesia. The cooperation and relaxation of the patient are very significant factors in enabling the operator to accomplish successfully his goal. To gain this end the procedure should be described to the patient with the assurance that there will be no interference with respiration. The importance of complete muscular relaxation of the entire body, particularly of the neck, shoulders and arms, should be stressed. The patient should remain passive and try to control his breathing in a quiet and regular manner. No food should be allowed for six hours prior to the examination whether local or general anesthesia is to be used, so that vomiting can be avoided and the danger of inhaling vomitus is reduced to a minimum. The administration of adequate medication for sedation contributes considerably to the preparation of patients for these procedures. It must be realized that different dosage is required to relax both mind and musculature of different people and it is therefore helpful to evaluate each patient's possible and likely reactions to laryngoscopy. It is our custom to administer secobarbital sodium (Seconal) 100 mg. and morphine sulfate 15 mg. with atropine sulfate 0.4 mg. to the average adult one hour before laryngoscopy. With this as a base the dosage can be varied for patients according to their needs. A very apprehensive patient might be given secobarbital sodium 200 mg., while a large, tense, muscular patient might relax better with morphine sulfate 30 mg. Infants are given no medication, while young children usually are prepared with secobarbital sodium 45 mg. suppository. It has been our impression that morphine stands alone among all such drugs in inducing the kind of relaxation most desirable for endoscopic respiratory procedures. Before elective laryngoscopic procedures are done, the patient's dental status should be made secure. ANESTHESIA
As a rule, general anesthesia (ether) is required in direct laryngoscopy in children above the age of two or three years. This frequently does not apply to sick children, as in laryngotracheobronchitis. Infants and very young children can be laryngoscoped without anesthesia and without trauma provided instrumentation is carried out gently. It is important to restrain the child well (by mummification) so that he can be controlled during the procedure. Laryngoscopy, both indirect and direct, can be performed with ease in adults under topical anesthesia. Anesthetics used vary in different clinics, but cocaine and Pontocaine appear to be the most popular. We favor cocaine in adults because this anesthetic drug is still the most effective topical anesthetic agent. Ten drops of a 1 per cent solution of Neo-Synephrine are added to the ounce of cocaine solution. We use 5
Laryngoscopy
1307
and 10 per cent cocaine solution for older children and young adults, and a 20 per cent solution for older adults. Anesthesia is first obtained on the lip, gums, tongue, palate, uvula, faucial pillars, posterior pharyngeal wall, then on the laryngeal structures as they descend. Cotton applicators soaked with a cocaine solution from which the excess has been squeezed out and small amounts of cocaine dropped into the larynx with a laryngeal syringe are used to produce anesthesia. We advise against the use of the laryngeal spray because of the possible rapid pulmonary absorption of large amounts of cocaine and its toxic effects. Similarly, the amount of cocaine dropped into the trachea should also be limited. The symptoms and signs of cocaine poisoning should be well known to anyone who employs it as an anesthetic agent, and Pentothal sodium should be available where cocaine is used. The use of the suspension or self-retaining laryngoscope requires the employment of deep general anesthesia. Suspension laryngoscopy may, however, be attempted under local anesthesia, but then heavy sedation and thorough cocainization are required. SPHERE OF LARYNGOSCOPY (INDIRECT AND DIRECT)
In examining the larynx the practice of scrutinizing each part together with the adjoining structures, separately and completely, must be developed. The examination should include the epiglottis, aryepiglottic folds, arytenoids, false cords, ventricles, true cords, anterior and posterior commissures, trachea and the pyriform sinuses. Special attention, of course, should be paid to the motion of the vocal cords and the arytenoids. Laryngoscopy should be used to determine the causes for changes in voice and obstruction to respiration. These may be foreign bodies, edema, secondary to specific and nonspecific infection or vocal strain, ulcerations, and benign or malignant or inflammatory new growths. To illustrate, in infants and young children, the lodgment of a foreign body or the presence of a hemangioma or papilloma or the existence of subglottic edema as part of laryngotracheobronchitis may be responsible for obstructed respiration and can be detected by direct laryngoscopy. In adults, mirror laryngoscopy will reveal a paralyzed vocal cord to explain phonesthenia or a neoplasm or ulceration of the vocal cord or an edematous infiltrated arytenoid to account for hoarseness. Bowed vocal cords with a triangular space at the posterior commissure on adduction of the vocal cords may suggest an hysterical condition in a patient with phonasthenia. Thus, whatever the lesion may be in the larynx, it can be brought into full view by laryngoscopy. Before definitive treatment is instituted, histopathological study of neoplastic or ulcerative tissue by means of biopsy is mandatory to estab-
1308
Joseph L. Goldman, Harry Talbot
lish the correct diagnosis. The indirect method of laryngoscopy is very useful for this type of procedure. Both the indirect and direct methods can be employed for the removal of foreign bodies and benign neoplasms, the stripping of polypoid vocal cords, the evacuation of cysts, the application of medication, the replacement of a dislocated arytenoid. Suspension laryngoscopy permits the performance of more elaborate operative interventions such as arytenoidectomies (Thorne1l 8) and the removal of large benign tumors and even small cordal carcinomas (LeJeune 9). ADVANTAGES AND DISADVANTAGES OF INDIRECT AND DIRECT LARYNGOSCOPY
Advantages of Indirect Laryngoscopy. This examination is a simple procedure which can be performed with little equipment. A head mirror with a spotlight or a headlight, a laryngeal mirror and an alcohol lamp only are necessary. The examination can be made almost anywhere and at any time. Its performance requires little effort on the part of the patient and doctor; it is painless, and is never dangerous. The problem of gagging usually can be overcome by the employment of local anesthesia, while apprehension is reduced by assurance and sedation. A large percentage of benign lesions of the larynx can be removed and treated by this simple method once the technique is mastered. Disadvantages of Indirect Laryngoscopy. The mirror image of the larynx is inverted and foreshortened in the anteroposterior diameter. As a result, the apparent length of the vocal cords and aryepiglottic folds is reduced. Also, a relatively false impression is obtained of the depth of the larynx, which appears more shallow in the mirror than it really is. These visual disadvantages are eliminated by practice and experience. The most significant disadvantage of this method is the difficulty that is encountered in inspecting invasive lesions of the ventricles and subglottic area and in defining the limits of tumors. Advantages of Direct Laryngoscopy. The important disadvantages mentioned in the last sentence can be obviated by direct laryngoscopy. Parenthetically, we would like to point out that tomography of the larynx is a highly effective means of delineating tumors. Direct laryngoscopy is usually the only method whereby the larynx of the infant or young child can be examined. Direct laryngoscopy, particularly the suspension variety, permits the surgeon to cope with more involved surgical procedures. Disadvantages of Direct Laryngoscopy. The procedure may be uncomfortable and even painful and traumatic. At times the patient may become quite alarmed during the procedure. 10 Not infrequently direct laryngoscopy may induce laryngeal spasm which distorts the true laryngeal picture. Small, soft tumors of the vocal cords will lose the sharpness of their borders because of the stretching of the vocal cords which results from the suspension effect of direct laryngoscopy. Finally,
Laryngoscopy
1309
the contraindications to direct laryngoscopy are curvature or injury of the cervical spine, heart failure and laryngeal obstruction which requires tracheostomy. REFERENCES 1. Yankauer: Laryngology. Edited by Coates, Schenk and Miller (Lejeune &
Lynch). Vol. 4., Chap. 26: 2--4, 1956. 2. Bruening, W.: Die Direkte Laryngoscopie, Bronchoscopie und Oesophagoscopie. Wiesbaden, J. F. Bergman, 1909. 3. Negus, V. E.: Diseases of Nose and Throat. 2nd. Ed. New York, 1947. 4. Roberts, S. and Forman, F. S.: Ann. Otol., Rhin. & Laryng. 57: 245-256 (March) 1948. 5. King, N. E.: A.M.A. Arch. Otolaryng. 53: 89-92 (Jan.) 1951. 6. Somers, K.: A.M.A. Arch. Otolaryng. 55: 484 (April) 1952. 7. Lewy, R. S.: Laryngoscope 64: 693 (Aug.) 1954. 8. Thornell, W. C.: Surg., Gynec. & Obst. 95: 63-66 (July) 1952. 9. Lejeune, F. E.: Mississippi Doctor 17: 83-84 (July) 1939. 10. Jackson, C. and Jackson, C. L.: Diseases of Nose, Throat & Ear. Philadelphia, W. B. Saunders Co., 1945, p. 434. 1050 Park Avenue New York 28, N.Y.
LARYNGOSCOPY presents the means to inspect and treat the larynx which is comparatively more accessible for examination and application of therapy than most organs because of its location in the upper respiratory tract. It is this accessibility which permits visualization of the larynx by two different methods, indirect or mirror laryngoscopy and direct laryngoscopy. While both methods offer the opportunity for examination and instrumentation, each has certain inherent advantages. At times both methods must be used to provide the best results for examiner and patient.
INDIRECT LARYNGOSCOPY
Indirect or mirror laryngology can be accomplished with ease, and the gag reflex which may offer difficulty can be controlled. Interns and residents in medicine and surgery should be trained in the use of the laryngeal mirror. Routine laryngeal examinations performed by the internist will uncover lesions in the larynx at an early stage as he is usually the first clinician to see this patient. At least, deviations from the normal, if not specific lesions, will be detected in the early phases of the disease, and thus the help of the laryngologist can be sought at an earlier stage. In performing mirror laryngoscopy, a clear, bright light, either reflected or from a headlight, is essential. The examiner and the patient should be seated opposite each other, the patient leaning slightly forward with the tongue protruded. The tip of the tongue is covered with gauze and is held out by the thumb and middle finger while the index finger holds away the upper lip. The tongue should not be pressed too firmly or pulled too hard lest this cause pain. In particular, if there are sharp or jagged lower teeth, the under surface of the tongue should be protected from any trauma. Any painful maneuver results in the loss of the pa* Head of Department of Otolaryngology, The Mount Sinai Hospital; Clinical Professor of Otolaryngology, College of Physicians and Surgeons, Columbia University, New
York, N. Y.
** Senior Resident, Department of Otolaryngology, 1301
The Mount Sinai Hospital.
1302
Joseph L. Goldman, Harry Talbot
tient's cooperation, the important prerequisite for easy and adequate visualization of the larynx. After the patient is instructed to breathe steadily throughout the procedure, the previously warmed mirror (to prevent condensation) is introduced into the back of the mouth so as to lie against the base of the uvula and soft palate. To be certain that the mirror is not hot enough to bum the patient, it should be tested either on the back of the hand, the thenar eminence, or cheek of the examiner. Care should be exercised that the mirror does not touch the dorsum of the tongue as this may induce the gag reflex in most patients. The tongue of some persons seem to be insensitive to such manipulations. Finally, the examiner gently pushes back the uvula and the soft palate to the posterior pharyngeal wall. By tilting the mirror to the proper angle, which can be correctly judged only after practice and experience, the structures from the base of the tongue to even the upper tracheal rings can be brought into view. A more complete view of the anterior portions of the vocal cords and of the anterior commissure is obtained through the phonating mechanism of raising the epiglottis by having the patient attempt to say "e" or "a". If the gag reflex is marked, visualization may be impossible without anesthetizing the pharynx and occasionally also the larynx. Sometimes the epiglottis obstructs a clear view of the larynx. In such cases, after satisfactory local anesthesia, the patient is instructed to hold the tongue forward with the right hand, the mirror is introduced with the left hand in the manner previously described, and with the other hand, a suitably curved epiglottis retractor (for this the curved tip of the standard laryngeal syringe is useful) is introduced over the base of the tongue under indirect vision to the posterior surface of the epiglottis. The latter is then gently pulled forward and slightly upward in order to expose the larynx more fully. The indirect method of laryngeal examination offers the opportunity for conclusive diagnostic evaluation by inspection in most cases. Although the image of the larynx is inverted and foreshortened, depending on the angle of the mirror in the mouth, an accurate appraisal of the larynx can be obtained by the experienced examiner. Also, surgical procedures of considerable variety can be executed by this method by using laryngeal punch tips and curved knives, but skill acquired by long and diligent training is necessary to master the technique involved. DIRECT LARYNGOSCOPY
Instrument. The variations in designs of direct laryngoscopes have been dependent on different sources of illumination and fixity of the handle. The earliest instruments ~arried the lighting proximally attached to the handle (Kirstein, Yankauerl [Fig. 355], Bruening2 [Fig. 356]). A frontal headlight also could serve the purpose of proximal illumination. The men who relied on proximal illumination similarly favored the detachable
Laryngoscopy
1303
Fig. 355. The Yankauer speculum, with proximal lighting. (Courtesy of W. F. Prior Company, Inc.)
type of handle into which fitted a rectangular metal bar (Bruening, Yankauer). The most commonly used laryngoscope is the tube-handle type as exemplified by the Jackson instrument (Fig. 357) or one of its modifications (Holinger, Andrews). It is the shortest of tubes used in endoscopic procedures. It relies on distal illumination, and, as the name implies, it consists of a tube with a permanently attached handle. The sizes vary from infants' to adults'. Essentially the laryngoscope is a rigid metal
Fig. 356. Bruening's handle with proximal lighting and wire cord attachment.
1304
Joseph L. Goldman, Harry Talbot
Fig. 357. A, Jackson's laryngoscope, adult size. B, Jackson's laryngoscope, infant size.
tube between 4 and 7 inches long, at the distal end of which is a lipped blade or speculum. The Negus3laryngoscope (Fig. 358) differs mainly from this in that it offers a dual lighting system. The beams begin about one-quarter of the way down the tube and cross each other at the distal end where the greatest concentration of light is produced. Position. Laryngoscopy is performed, as a rule, with the patient in the dorsal recumbent position. The position of the head often determines the ease or difficulty with which the examination can be performed. The head, neck and shoulders beyond the spines of the scapulae should project over the end of the table. The head is supported in such a way that it can be raised and extended at the atlanto-occipital joint. This position is best maintained by an assistant, although some form of special head rest fixed to the table is used occasionally. The raising of the shoulders during the procedure should be avoided. Examination. The Jackson laryngoscope is introduced with the left hand while the Bruening handle is held with the right. Care must be exercised to protect the upper lip and teeth from trauma. At no time should the teeth be used as a fulcrum. It is usual to pass the laryngoscope over the right side of the tongue towards the middle of the base of the tongue with the object of bringing the epiglottis into view. It is sometimes necessary to elevate the base of the tongue to accomplish this and it may be helpful to pull the tongue forward. The descent of the laryngoscope is then carried directly forward until the posterior surface"'of the epiglottis is engaged. At this point exposure of the larynx depends on skill rather than strength and is accomplished by lifting the spatular end of the laryngoscope upward and forward by a tilting motion of the wrist.
Laryngoscopy
1305
Fig. 358. The Negus twin-illuminated laryngoscope.
The larynx is kept in view by maintaining the structures anterior to the epiglottis in suspension. Maneuvers may be required to expose the ventricles and a special anterior commissure laryngoscope (Jackson) to examine the subglottic area. Suspension Laryngoscopy. Suspension laryngoscopy is an elaboration of the direct procedure and was designed to leave both hands of the surgeon free for operative intervention. The working principle of the apparatus depends on the suspension of a tongue blade, attached to a mouth gag, by a crane arrangement fixed to the operating table. The tongue blade exposes the larynx. The Lynch modification of the original Killian instrument is the one that is generally used for this purpose at present. In recent years the suspension of the larynx by self-retaining supports which rest on the chest have been used with increasing popularity. There have been a number of instruments of this type since Roberts and Forman4 reintroduced this method. King 5 devised an instrument which he called a "stabilizer" for use with the Jackson laryngoscope and Somers 6 described another type of self-retaining attachment for the laryngoscope. This was followed by the Andrews chest support, and finally in 1954, Lewy7 presented his instrument which combined many of the best features of the self-retaining chest supports which had been in use previously. PREPARATION OF PATIENT FOR OPERATIVE PROCEDURES
This phase of the discussion is concerned with direct laryngoscopy as regards both examination and operative procedures and with the indirect
1308
Joseph L. Goldman, Harry Talbot
method when operative intervention is contemplated, and deserves consideration because these procedures are usually performed under local anesthesia. The cooperation and relaxation of the patient are very significant factors in enabling the operator to accomplish successfully his goal. To gain this end the procedure should be described to the patient with the assurance that there will be no interference with respiration. The importance of complete muscular relaxation of the entire body, particularly of the neck, shoulders and arms, should be stressed. The patient should remain passive and try to control his breathing in a quiet and regular manner. No food should be allowed for six hours prior to the examination whether local or general anesthesia is to be used, so that vomiting can be avoided and the danger of inhaling vomitus is reduced to a minimum. The administration of adequate medication for sedation contributes considerably to the preparation of patients for these procedures. It must be realized that different dosage is required to relax both mind and musculature of different people and it is therefore helpful to evaluate each patient's possible and likely reactions to laryngoscopy. It is our custom to administer secobarbital sodium (Seconal) 100 mg. and morphine sulfate 15 mg. with atropine sulfate 0.4 mg. to the average adult one hour before laryngoscopy. With this as a base the dosage can be varied for patients according to their needs. A very apprehensive patient might be given secobarbital sodium 200 mg., while a large, tense, muscular patient might relax better with morphine sulfate 30 mg. Infants are given no medication, while young children usually are prepared with secobarbital sodium 45 mg. suppository. It has been our impression that morphine stands alone among all such drugs in inducing the kind of relaxation most desirable for endoscopic respiratory procedures. Before elective laryngoscopic procedures are done, the patient's dental status should be made secure. ANESTHESIA
As a rule, general anesthesia (ether) is required in direct laryngoscopy in children above the age of two or three years. This frequently does not apply to sick children, as in laryngotracheobronchitis. Infants and very young children can be laryngoscoped without anesthesia and without trauma provided instrumentation is carried out gently. It is important to restrain the child well (by mummification) so that he can be controlled during the procedure. Laryngoscopy, both indirect and direct, can be performed with ease in adults under topical anesthesia. Anesthetics used vary in different clinics, but cocaine and Pontocaine appear to be the most popular. We favor cocaine in adults because this anesthetic drug is still the most effective topical anesthetic agent. Ten drops of a 1 per cent solution of Neo-Synephrine are added to the ounce of cocaine solution. We use 5
Laryngoscopy
1307
and 10 per cent cocaine solution for older children and young adults, and a 20 per cent solution for older adults. Anesthesia is first obtained on the lip, gums, tongue, palate, uvula, faucial pillars, posterior pharyngeal wall, then on the laryngeal structures as they descend. Cotton applicators soaked with a cocaine solution from which the excess has been squeezed out and small amounts of cocaine dropped into the larynx with a laryngeal syringe are used to produce anesthesia. We advise against the use of the laryngeal spray because of the possible rapid pulmonary absorption of large amounts of cocaine and its toxic effects. Similarly, the amount of cocaine dropped into the trachea should also be limited. The symptoms and signs of cocaine poisoning should be well known to anyone who employs it as an anesthetic agent, and Pentothal sodium should be available where cocaine is used. The use of the suspension or self-retaining laryngoscope requires the employment of deep general anesthesia. Suspension laryngoscopy may, however, be attempted under local anesthesia, but then heavy sedation and thorough cocainization are required. SPHERE OF LARYNGOSCOPY (INDIRECT AND DIRECT)
In examining the larynx the practice of scrutinizing each part together with the adjoining structures, separately and completely, must be developed. The examination should include the epiglottis, aryepiglottic folds, arytenoids, false cords, ventricles, true cords, anterior and posterior commissures, trachea and the pyriform sinuses. Special attention, of course, should be paid to the motion of the vocal cords and the arytenoids. Laryngoscopy should be used to determine the causes for changes in voice and obstruction to respiration. These may be foreign bodies, edema, secondary to specific and nonspecific infection or vocal strain, ulcerations, and benign or malignant or inflammatory new growths. To illustrate, in infants and young children, the lodgment of a foreign body or the presence of a hemangioma or papilloma or the existence of subglottic edema as part of laryngotracheobronchitis may be responsible for obstructed respiration and can be detected by direct laryngoscopy. In adults, mirror laryngoscopy will reveal a paralyzed vocal cord to explain phonesthenia or a neoplasm or ulceration of the vocal cord or an edematous infiltrated arytenoid to account for hoarseness. Bowed vocal cords with a triangular space at the posterior commissure on adduction of the vocal cords may suggest an hysterical condition in a patient with phonasthenia. Thus, whatever the lesion may be in the larynx, it can be brought into full view by laryngoscopy. Before definitive treatment is instituted, histopathological study of neoplastic or ulcerative tissue by means of biopsy is mandatory to estab-
1308
Joseph L. Goldman, Harry Talbot
lish the correct diagnosis. The indirect method of laryngoscopy is very useful for this type of procedure. Both the indirect and direct methods can be employed for the removal of foreign bodies and benign neoplasms, the stripping of polypoid vocal cords, the evacuation of cysts, the application of medication, the replacement of a dislocated arytenoid. Suspension laryngoscopy permits the performance of more elaborate operative interventions such as arytenoidectomies (Thorne1l 8) and the removal of large benign tumors and even small cordal carcinomas (LeJeune 9). ADVANTAGES AND DISADVANTAGES OF INDIRECT AND DIRECT LARYNGOSCOPY
Advantages of Indirect Laryngoscopy. This examination is a simple procedure which can be performed with little equipment. A head mirror with a spotlight or a headlight, a laryngeal mirror and an alcohol lamp only are necessary. The examination can be made almost anywhere and at any time. Its performance requires little effort on the part of the patient and doctor; it is painless, and is never dangerous. The problem of gagging usually can be overcome by the employment of local anesthesia, while apprehension is reduced by assurance and sedation. A large percentage of benign lesions of the larynx can be removed and treated by this simple method once the technique is mastered. Disadvantages of Indirect Laryngoscopy. The mirror image of the larynx is inverted and foreshortened in the anteroposterior diameter. As a result, the apparent length of the vocal cords and aryepiglottic folds is reduced. Also, a relatively false impression is obtained of the depth of the larynx, which appears more shallow in the mirror than it really is. These visual disadvantages are eliminated by practice and experience. The most significant disadvantage of this method is the difficulty that is encountered in inspecting invasive lesions of the ventricles and subglottic area and in defining the limits of tumors. Advantages of Direct Laryngoscopy. The important disadvantages mentioned in the last sentence can be obviated by direct laryngoscopy. Parenthetically, we would like to point out that tomography of the larynx is a highly effective means of delineating tumors. Direct laryngoscopy is usually the only method whereby the larynx of the infant or young child can be examined. Direct laryngoscopy, particularly the suspension variety, permits the surgeon to cope with more involved surgical procedures. Disadvantages of Direct Laryngoscopy. The procedure may be uncomfortable and even painful and traumatic. At times the patient may become quite alarmed during the procedure. 10 Not infrequently direct laryngoscopy may induce laryngeal spasm which distorts the true laryngeal picture. Small, soft tumors of the vocal cords will lose the sharpness of their borders because of the stretching of the vocal cords which results from the suspension effect of direct laryngoscopy. Finally,
Laryngoscopy
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the contraindications to direct laryngoscopy are curvature or injury of the cervical spine, heart failure and laryngeal obstruction which requires tracheostomy. REFERENCES 1. Yankauer: Laryngology. Edited by Coates, Schenk and Miller (Lejeune &
Lynch). Vol. 4., Chap. 26: 2--4, 1956. 2. Bruening, W.: Die Direkte Laryngoscopie, Bronchoscopie und Oesophagoscopie. Wiesbaden, J. F. Bergman, 1909. 3. Negus, V. E.: Diseases of Nose and Throat. 2nd. Ed. New York, 1947. 4. Roberts, S. and Forman, F. S.: Ann. Otol., Rhin. & Laryng. 57: 245-256 (March) 1948. 5. King, N. E.: A.M.A. Arch. Otolaryng. 53: 89-92 (Jan.) 1951. 6. Somers, K.: A.M.A. Arch. Otolaryng. 55: 484 (April) 1952. 7. Lewy, R. S.: Laryngoscope 64: 693 (Aug.) 1954. 8. Thornell, W. C.: Surg., Gynec. & Obst. 95: 63-66 (July) 1952. 9. Lejeune, F. E.: Mississippi Doctor 17: 83-84 (July) 1939. 10. Jackson, C. and Jackson, C. L.: Diseases of Nose, Throat & Ear. Philadelphia, W. B. Saunders Co., 1945, p. 434. 1050 Park Avenue New York 28, N.Y.