Toward the Surgical Treatment of Paralytic (Median) Laryngeal Stenoses

The dissertation is devoted to the problem of surgical treatment of paralytic (median) laryngeal stenoses arising from damage to the recurrent laryngeal nerve and its branches. The work develops differential-diagnostic tables for determining the localization of vagus nerve damage at various levels — from the central nervous system to the peripheral divisions. Modified surgical techniques are proposed, including extralaryngeal lateralization of the vocal fold with formation of ankylosis in the cricoarytenoid joint, as well as lateralization on an open larynx when paralytic stenosis is combined with other variants of obstruction of the upper respiratory tract. The investigation also addresses improving methods of local anesthesia and replacing cannulated tracheostomy with decannulated tracheostomy. The clinical base of the work includes analysis of medical records of 37 patients with paralytic laryngeal stenosis and 189 patients with disorders of vagus nerve functions.

Despite significant advances in modern clinical medicine and basic disciplines, many problems of the diagnostic and therapeutic plan have not acquired a final solution. This fully applies to certain questions of laryngology. In this regard, the problem of treating voice function disorders caused by damage to the vagus nerve and its branches, as well as formations of the skull base and higher-located sections of the CNS, is no exception. The overwhelming majority of the latter are distinguished by particular severity. In some cases they are characterized not only by noted, but also by irreversibility of consequences. Often, determining the localization of such a process and its etiology, if it enters the competence of an otolaryngologist at all, is only within the scope of consultations regarding the detection of those changes that can be seen and assessed using methods of ENT examination. However, this does not mean that the causes underlying impairment of the functions of the intrinsic laryngeal muscles associated with damage to the recurrent laryngeal nerve cannot be the subject of interest and application of the professional capabilities of otorhinolaryngologists-head and neck surgeons. Therefore, it is not surprising that many named specialists have devoted and continue to devote their efforts to this branch of practical medicine, aimed at correcting voice and respiratory function disorders, the cause of which is functional insufficiency of the specified nerve [2, 15, 26, 28, 60, 75, 91, 143, 148]. They have described and developed numerous variants of treatment, including surgical, mainly reducing in the case of unilateral immobility and atony of the vocal fold to its medialization and restoration of tone [73, 103, 118, 121], and in the case of bilateral damage causing paralytic laryngeal stenosis, to its lateralization [26, 28, 107, 108, 112, 120]. Despite the above, gaps sometimes still appear in textbooks, even popular and recognized as desk-top ones, relating to the noted variants of correction of the listed disorders [3]. It is not excluded that the reason for such an attitude toward them is their large number and the absence of standard ones suitable for most patients. Moreover, the problem of their treatment is complicated by a number of factors, sometimes requiring an individual and original solution. Among them one can cite the genesis and the features of combined damage to the recurrent laryngeal nerve and diseases of the respiratory tract causing obstruction at other levels [5, 27, 47, 52]. Taking this into account, one can consider that the problem of patient selection and their treatment regarding voice and respiratory function disorders associated respectively with unilateral and bilateral damage to the recurrent laryngeal nerve retains its relevance. This served as the basis for choosing the topic.

Research objective: To increase the effectiveness and reliability of surgical treatment aimed at eliminating difficult breathing through natural pathways in patients with paralytic laryngeal stenosis. Research tasks:

1. To develop differential-diagnostic tables facilitating the determination of the localization of the process causing voice and breathing disorders associated with unilateral and bilateral impairment of recurrent laryngeal nerve function.

2. To increase the effectiveness of local and regional anesthesia combined with neuroleptoanalgesia, allowing control of breathing through natural pathways against the background of complete anesthesia of the operation, when performed on an open larynx and in the presence of a stable decannulated tracheostomy.

3. To work out the methodological foundations for performing extralaryngeal lateralization of the vocal fold aimed at restoring breathing in paralytic laryngeal stenosis, distinguished by a stable result.

4. To demonstrate the advantages of decannulated tracheostomy instead of cannulated, as a means facilitating the condition of patients operated on for paralytic laryngeal stenosis.

5. To present indications and methodological foundations for performing lateralization of the vocal fold on an open larynx for patients in whom paralytic stenosis is combined with other variants of obstruction in the upper sections of the respiratory tract.

Scientific novelty

1. The method of performing local infiltrative anesthesia combined with bilateral blockade of the superior laryngeal nerve and the SLN, with submucosal injection of novocaine (lidocaine) into the area of the subglottic part of the larynx and the initial part of the trachea through a decannulated tracheostomy or when performing the operation on the open organ, is supplemented.

2. A modified variant of performing extralaryngeal lateralization of the vocal fold is proposed, including, among other things, opening the cricoarytenoid joint to form its ankylosis, providing a stable result of surgical treatment of paralytic laryngeal stenosis.

3. A modified variant of performing lateralization of the vocal fold on an open larynx is developed for patients in whom paralytic laryngeal stenosis is combined with other variants of obstruction in the upper sections of the respiratory tract.

4. For the first time, it is recommended to perform a decannulated temporary or permanent tracheostomy instead of a cannulated one in the case of paralytic laryngeal stenosis.

Practical significance of the obtained data

1. The proposed differential-diagnostic tables facilitate the otolaryngologist and other specialists in determining the localization of vagus nerve damage at the level of the CNS, basiocranial, and peripheral zones, and thus enable, including proper selection of patients for whom surgery for paralytic laryngeal stenosis is indicated.

2. The recommendation to supplement local anesthesia combined with blockade of the superior laryngeal nerves and the SLN with submucosal injection of an anesthetic into the subglottic space and the initial part of the trachea ensures complete painless operation, calm behavior of the patient, and allows the surgeon to control the result of surgical treatment.

3. The modified method of performing extralaryngeal lateralization of the vocal fold, thanks to the development of ankylosis in the cricoarytenoid joint, prevents possible medialization of the vocal fold displaced to the side, and thus this addition during the named operation prevents recurrence of paralytic laryngeal stenosis.

4. The developed technique of lateral positioning of the vocal fold using sutures pulling the vocal fold toward the thyroid cartilage lamina on an open larynx is indicated for combined variants of obstruction of the lumen of the respiratory tract, facilitates solving a complex practical task, does not require special instrumentation and the work of two surgical teams, which is necessary when solving the same task performed by an extralaryngeal method.

Recommendation, depending on indications, to form a temporary or permanent decannulated tracheostomy facilitates the condition of patients and prevents, instead of a cannulated one, the development of an inflammatory process in the respiratory tract and frees patients from paroxysms of cough, which negatively affect the condition of operated patients.

Positions for defense

1. Differential-diagnostic tables facilitating the establishment of a local diagnosis of vagus nerve damage and its branches, including those relating to the recurrent laryngeal nerve.

2. Local anesthesia of laryngeal operations, including in the case of paralytic stenosis, supplemented not only with blockade of the superior laryngeal nerves but also with elimination of sensitive receptor perception from the subglottic space and the initial part of the trachea by submucosal introduction of a novocaine (lidocaine) solution into them, providing calm behavior of patients and control over the functional state of the larynx during the performance of the operation.

3. Modified variants of performing operations both by the extralaryngeal approach and on an open larynx, which allow obtaining a stable result in restoring breathing through natural pathways, impaired in connection with paralytic laryngeal stenosis.

Implementation of the obtained results

The results of the investigations have been introduced into the practice of the otorhinolaryngology-head and neck surgery department of the National Hospital under the Ministry of Health of the Kyrgyz Republic.

The main provisions of the dissertation work are used in teaching otolaryngology — during lectures and when conducting practical classes intended for clinical residents, postgraduate students, and physicians undergoing retraining and improvement at the Department of SKD-2 of the Kyrgyz-Russian Slavic University and in the course of otolaryngology-head and neck surgery of the Kyrgyz Medical Institute for retraining and improvement of qualifications.

Author's personal contribution

The main base material relating to the topic of the presented work, based on the analysis of medical records of 37 patients with paralytic laryngeal stenosis and 189 patients with disorders of vagus nerve functions etiologically associated with diseases of the CNS and neck, including those having inflammatory and tumor nature, was completed entirely by the author of the work.

In addition, he took direct part in the examination, preparation for surgical intervention, and during its performance in half of the patients operated on for paralytic stenosis. Dissertation defense

The main provisions of the dissertation have been published in the periodical press. The work was tested and discussed at the Department of SKD-2 of the Kyrgyz-Russian Slavic University and in the course of otolaryngology-head and neck surgery of the Kyrgyz Medical Institute for retraining and improvement of qualifications. Fragments of the work were reported at the Xth Anniversary Meeting of the International Academy of Head and Neck Surgery and the Jubilee Congress of Otolaryngologists of Kyrgyzstan (Bishkek, 2001); at the I International Congress of Rhinologists of Kazakhstan (Almaty, 2002); at the scientific-practical conference dedicated to the 60th anniversary of KGMA and the International Year of Mountains (Naryn, 2002); at the XXI International Conference of Young Scientists (St. Petersburg, 2004); at the XVI Annual International Conference of Otolaryngologists-Head and Neck Surgeons (St. Petersburg, 2005); at the Annual Scientific Conference of the Medical Faculty of KRSLU (Bishkek, 2007); at the meeting of the expert commission of the Dissertation Council D 730.001.03. at the Kyrgyz-Russian Slavic University for preliminary consideration of dissertations in specialties 14.00.27 — surgery, 14.00.04 — diseases of the ear, nose, and throat (Bishkek, 2007).

Publications on the dissertation topic

Based on the materials of the dissertation, 10 articles and 1 monograph have been published.

Structure and volume of the dissertation

The dissertation is written in Russian, on 137 pages. It consists of an introduction, 4 chapters, conclusion, conclusions, and a list of references including 159 sources, including those published in 56 domestic and 103 foreign sources of literature. The text is illustrated with 7 tables and 22 figures.