Subglottic edema is a complication rarely seen except in children under 3 years of age. They have a peculiar histologic structure in this region, as is shown by Logan Turner. Even at the predisposing age subglottic edema is a very unusual sequence to bronchoscopy if this region was previously normal. The passage of a bronchoscope through an already inflamed subglottic area is liable to be followed by a temporary increase in the swelling. If the foreign body be associated with but slight amount of secretion, the child can usually obtain sufficient air through the temporarily narrowed lumen. If, however, as in cases of arachidic bronchitis, large amounts of purulent secretion must be expelled, it will be found in certain cases that the decreased glottic lumen and impaired laryngeal motility will render tracheotomy necessary to drain the lungs and prevent drowning in the retained secretions. Subglottic edema occurring in a previously normal larynx may result from: 1. The use of over-sized tubes. 2. Prolonged bronchoscopy. 3. Faulty position of the patient, the axis of the tube not being in that of the trachea. 4. Trauma from undue force or improper direction in the insertion of the bronchoscope. 5. The manipulation of instruments. 6. Trauma inflicted in the extraction of the foreign body.
Diagnosis must be made without waiting for cyanosis which may never appear. Pallor, restlessness, startled awakening after a few minutes sleep, occurring in a child with croupy cough, indrawing around the clavicles, in the intercostal spaces, at the suprasternal notch and at the epigastrium, call for tracheotomy which should always be low. Such a case should not be left unwatched. The child will become exhausted in its fight for air and will give up and die. The respiratory rate naturally increases because of air hunger, accumulating secretions that cannot be expelled because of impaired glottic motility give signs wrongly interpreted as pneumonia. Many children whose lives could have been saved by tracheotomy have died under this erroneous diagnosis.
Treatment.—Intubation is not so safe because the secretions cannot easily be expelled through the tube and postintubational stenosis may be produced. Low tracheotomy, the tracheal incision always below the second ring, is the safest and best method of treatment.
[156] CHAPTER XIV—REMOVAL OF FOREIGN BODIES FROM THE LARYNX
Symptoms and Diagnosis.—The history of a sudden choking attack followed by impairment of voice, wheezing, and more or less dyspnea can be usually elicited. Laryngeal diphtheria is the condition most frequently thought of when these symptoms are present, and antitoxin is rightly given while waiting for a positive diagnosis. Extreme dyspnea may render tracheotomy urgently demanded before any attempts at diagnosis are made. Further consideration of the symptomatology and diagnosis of laryngeal foreign body will be found on pages 128, 133 and 143.
Preliminary Examination.—In the adult, mirror examination of the larynx should be done, the patient being placed in the recumbent position. Whenever time permits roentgenograms, lateral and anteroposterior, should be made, the lateral one as low in the neck as possible. One might think this an unnecessary procedure because of the visibility of the larynx in the mirror; but a child's larynx cannot usually be indirectly examined, and even in the adult a pin may be so situated that neither head nor point is visible, only a portion of the shaft being seen. The roentgenogram will give accurate information as to the position, and will thus allow a planning of the best method for removal of the foreign body. A bone in the larynx usually is visible in a good roentgenogram. Accurate diagnosis in children is made by direct laryngoscopy without anesthesia, but direct laryngoscopy should not be done until one is prepared to remove a foreign body if found, to follow it into the bronchus and remove it if it should be dislodged and aspirated, and to do tracheotomy if sudden respiratory arrest occur.
[157] Technic of Removal of Foreign Bodies from the Larynx.—The patient is to be placed in the author's position, shown in Fig. 53. No general anesthesia should be given, and the application of local anesthesia is usually unnecessary and further, is liable to dislodge and push down the foreign body.* Because of the risk of loss downward it is best to seize the foreign body as soon as seen; then to determine how best to disimpact it. The fundamental principles are that a pointed object must either have its point protected by the forceps grasp or be brought out point trailing, and that a flat object must be so rotated that its plane corresponds to the sagittal plane of the glottic chink. The laryngeal grasping forceps (Fig. 53) will be found the most useful, although the alligator rotation forceps (Fig. 31) may occasionally be required.
* In adolescents or adults a few drops of a 4 per cent solution of cocain applied to the laryngopharynx with an atomizer or a dropper will afford the minimum risk of dislodgement; but the author's personal preference is for no anesthesia, general or local.
[158] CHAPTER XV—MECHANICAL PROBLEMS OF BRONCHOSCOPIC FOREIGN BODY EXTRACTION*
* For more extensive consideration of mechanical problems than is here possible the reader is referred to the Bibliography, page 311, especially reference numbers 1, 11, 37 and 56.