These are extremely rare.
a. Papilloma: It is the commonest benign tumor. It is probably caused by human papilloma virus. In adults,
it is usually single and presents as a pedunculated mass attached to vocal cords. The patient presents with hoarseness of voice. The diagnosis is made with laryngoscopic examination. The treatment is laser ablation or surgical excision since it may rarely become malignant. In children, papillomas are usually multiple with high tendency of recurrence. It is self-limiting condition and disappears spontaneously by adult life. Hence, it should not be subjected to radical excision for fear of damaging vocal cords.
b. Angiofibroma: It is always single and presents as a small, smooth, red colored mass on the vocal cord.
The patient presents with hoarseness of voice and hemoptysis. The diagnosis is made on laryngoscopic examination and the treatment is endoscopic removal or cryosurgery.
Malignant Tumors
Squamous cell carcinoma is the commonest tumor of larynx. It is the most common malignancy of the upper aerodigestive tract.
Incidence
It is most commonly seen in elderly male smokers.
However, sex incidence is changing due to increased smoking habits among women. The male to female ratio has dramatically decreased from 10 : 1 to 5 : 1 in last two decades.
Etiology
• Exposure to tobacco (smoking) is most important etiological factor.
• Other likely cofactors are:
Metal dust (Nickel) Wood dust
Asbestos Hair dyes
• There is some unclear relation between adult onset papilloma and carcinoma larynx.
Classification
There are three varieties of laryngeal carcinoma based on its location:
a. Glottic: It is the commonest variety. The tumor arises from true vocal cords involving anterior half. It is mostly papillary in appearance. Due to paucity of Box 16.1: Etiology of vocal cord palsy
Traumatic Thyroid surgery (commonest) Neck injury
Neoplastic Carcinoma larynx Carcinoma thyroid Carcinoma esophagus
Carcinoma lung involving left hilum Infective Viral infection
Vascular Aortic aneurysm
Neurological Lower motor neuron palsy
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Textbook of Surgery for Dental Studentslymphatic vessels in the vocal cords, it remains locally malignant for long time. The first symptom is hoarseness of voice that is progressive and may lead to stridor and aphonia. When tumor extends outside the glottis, it becomes aggressive and involves cervical lymph nodes. Due to slow growth, it has most favorable prognosis.
b. Subglottic: It is rare variety. The tumor arises below vocal cords. The tumor grows steadily and silently till dyspnea develops. Hoarseness of voice indicates late disease. The growth may involve thyroid gland and deep cervical lymph nodes.
c. Supraglottic: It is also called extrinsic laryngeal carcinoma and it involves false vocal cords, laryngeal ventricles and root of epiglottis. Due to abundant lymphatic supply, it presents with advanced stage disease and has worst prognosis. The patient presents with throat pain, hoarseness of voice and dysphagia.
Neck nodes are involved in majority of the cases.
Staging
TNM staging of carcinoma larynx is given in Box 16.2.
Investigations
• Hopkins rod examination allows precise determi-nation of extent of tumor.
• Direct laryngoscopy and biopsy confirms the diagnosis.
• CT and MRI are useful in determining the invasion of thyroid cartilage, suspicious nodal involvement in the neck and staging the disease.
Treatment
Early glottic and supraglottic tumors (stage I and II): are best treated with mega voltage radiotherapy. Dose is 60 Gy in 30 fractions over 6 weeks and cure rates are 90% and 70% in stage I and stage II respectively.
Advantage is of voice preservation after the treatment.
Alternative treatment for early tumors is excision by:
• Endoscopic laser surgery
• Laryngofissure in which thyroid cartilage is opened anteriorly in the midline and tumor removed under vision.
• Partial laryngectomy
However, voice result after surgery is not as satis-factory as that with radiotherapy.
Advanced Laryngeal Tumors
Treatment is total laryngectomy. It includes removal of entire larynx, hyoid bone, pre-epiglottic space, strap muscles and one or two tracheal rings with permanent tracheal stoma. When cervical lymph nodes are involved with secondary deposits, block dissection of lymph nodes is combined with laryngectomy.
Vocal Rehabilitation after Laryngectomy
For speech, vibrations are created in the pharynx by following ways:
i. Artificial larynx: It is a battery powered device that is applied to the soft tissues of neck creating a primary sound while the patient articulates to produce words.
ii. Esophageal voice: Patient swallows air into pharynx and upper esophagus. On regurgitation of air, pharyngo-esophageal mucosa vibrates to produce sound.
iii. Blom-Singer Valve: A simple tracheo-esophageal puncture is maintained patent by a small tube containing a valve. This one way valve allows air to pass from trachea into the pharynx but prevents back flow of food particles into the airway. The air entering into pharynx and esophagus is modulated by tongue, lips and buccal mucosa to produce voice. 80% of the patients are able to develop fluent speech.
iv. Larynx transplant has as yet been unsuccessful.
TRACHEOSTOMY
It is making an opening in anterior wall of the trachea and converting it into a stoma on skin surface.
Indications
1. Upper airway obstruction
• Foreign body
• Infection (diphtheria, Ludwig’s angina)
• Edema of glottis (head and neck burns)
• Bilateral vocal cord palsy
• Trauma (faciomaxillary, larynx, trachea)
• Tumor (carcinoma larynx)
• Congenital lesions (web, atresia)
• Chronic stenosis (Tuberculosis, scalding)
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2. Retained secretions
• Severe bronchopneumonia
• Chronic bronchitis
• Chest injury (Flail chest) 3. Respiratory insufficiency
• Head injury
• Bulbar poliomyelitis
• Barbiturate poisoning
• Tetanus
Aims of Tracheostomy
Aim is to assist respiration which it does in the following ways:
i. It relieves upper airway obstruction.
Box 16.2: TNM staging of carcinoma larynx Primary tumor (T)
Tx Tumor cannot be assessed T0 No evidence of primary tumor T1s Carcinoma in situ.
Supraglottis Glottis Subglottis
T1 Confined to site of origin with Tumor confined to vocal cords Tumor confined to subglottic region.
normal mobility. with normal mobility.
T2 Tumor involves adjacent Supraglottic or subglottic extension Tumor extension to vocal cords with supraglottic site or glottis with normal or impaired cord normal or impaired cord mobility.
without fixation. mobility.
T3 Tumor limited to larynx with Tumor confined to larynx with cord Tumor confined to larynx with cord extension to post-cricoid area, fixation. fixation.
medial wall of pyriform sinus or pre-epiglottic space.
T4 Tumor extends beyond larynx to Tumor extends beyond larynx to Tumor extends beyond larynx to involve oropharynx, soft tissues involve oropharynx, soft tissues of involve oropharynx, soft tissues of
of neck. neck. neck.
Regional lymph nodes (N)
Nx Lymph nodes cannot be assessed.
N0 No clinically positive nodes.
N1 Single homolateral node 3 cm or less in diameter.
N2a Single homolateral node 3-6 cm in diameter.
N2b Multiple homolateral nodes 3-6 cm in diameter.
N3 Massive nodes (>6 cm) Distant metastasis (M)
Mx Metastasis cannot be assessed.
M0 No distant metastasis.
M1 Distant metastasis present.
Stage grouping
Stage I T1 N0 M0 Stage-II T2 N0 M0
Stage III T1 N1M0, T2 N1M0, T3 N1M0
Stage IV T4 N0M0, Tany N2M0, Tany Nany M1
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Textbook of Surgery for Dental Studentsii. It reduces the anatomical dead space (150 ml).
iii. Toilet of tracheobronchial tree by giving direct access.
iv. Cuffed endotracheal tube protects the airways from aspiration and allows positive pressure ventilation to be maintained for a prolonged period.
However, all these objectives can be achieved, to some extent, by the use of endotracheal tube. But prolonged endotracheal intubation risks laryngeal damage and subglottic stenosis. Hence, tracheostomy is indicated when endotracheal intubation fails in emergency situations or prolonged ventilation is required (more than a week) in elective situations.
Advantages of tracheostomy over endotracheal intubation are:
i. Patients are more comfortable and require no sedation.
ii. It can be continued indefinitely.
iii. Suction and clearing of secretions is easier.
iv. Work of breathing is reduced.
v. Alveolar ventilation is increased.
vi. Weaning is easier with tracheostomy.
Disadvantages of tracheostomy are:
i. It is an open wound liable to infection.
ii. Loss of heat and moisture leading to desiccation and metaplasia of tracheal epithelium.
iii. Tracheostomy tube acts as a foreign body that stimulates mucus production in the trachea. The mucus gets encrusted and blocks the tube.
Types of Tracheostomy
i. Emergency: It is done for acute airway obstruction.
If facilities don’t exist and experienced doctor is not available, a large intravenous cannula may be inserted into cricothyroid membrane to relieve acute upper airway obstruction.
ii. Elective: During certain operations on upper airway.
iii. Permanent: Following laryngectomy.
Surgical Anatomy
The trachea begins as a continuation of the larynx at lower border of cricoid cartilage. It is superficial in the upper part and it becomes more deeply placed as it
descends. Its superficial relations include skin, platysma, investing layer of deep fascia, strap muscles (sternohyoid and sternothyroid), pretracheal fascia and isthmus of thyroid gland (overlies 2nd, 3rd and 4th tracheal rings).
The tissue planes in the midline are devoid of major veins.
Operation
a. Emergency Tracheostomy
Patient is placed in supine position. Neck is extended by placing pillow between shoulders (Fig. 16.2).
However, in a case of severe head and neck trauma with suspected cervical spine injury, it is safer to do cricothyroidotomy rather than tracheostomy. Local anesthesia is infiltrated (not required in deeply unconscious patient). 1-11/2" vertical skin incision is given below cricoid cartilage in the midline (Fig. 16.3).
Skin, platysma, deep fascia and pretracheal fascia are divided passing between infrahyoid muscles. If isthmus comes in the way, it is ligated and divided. A cricoid hook is then inserted under the cricoid cartilage and pulled up to stabilize the trachea and to bring it to the surface. The second, third and fourth tracheal rings are divided with a knife (Fig. 16.4). A trachea wound dilator is inserted to dilate the tracheal wound. A tracheostomy tube is then inserted into the trachea and dilator is removed (Fig. 16.5). Air movements through tracheostomy tube opening are felt with fingers to check its correct position. If tube is not placed correctly, it will lead to surgical emphysema and respiratory obstruction (Figs 16.6A and B). The cuff of tracheo-stomy tube is inflated to make it self-retaining. The tube
Fig. 16.2: Position of the patient for tracheostomy
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is attached with tapes that are tied around patient’s neck (Figs 16.7 and 16.10). Alternatively, the flanges of the plastic tube may be stitched directly to the underlying skin. The wound should be sutured lightly to prevent surgical emphysema.
Fig. 16.3: Emergency tracheostomy—vertical skin incision
Fig. 16.4: Emergency tracheostomy—incising the trachea
Fig. 16.5: Emergency tracheostomy—inserting the tracheostomy tube
Figs 16.6A and B: Checking position of tracheostomy tube—
(A) Tracheostomy tube in correct position, (B) Misplaced tracheostomy tube causing surgical emphysema
Fig. 16.7: Tracheostomy tube secured in a patient of head injury with fracture mandible
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Textbook of Surgery for Dental Studentsb. Elective Tracheostomy
The advantage of elective tracheostomy is that there is complete airway control, precise dissection and careful placement of appropriate tube.
After positioning, local or general anesthesia is given.
A transverse skin incision is given over third tracheal ring (it heals with less scarring) (Fig. 16.8). If performed under local anesthesia, injection of 2% xylocaine into trachea before incising prevents violent cough following insertion of the tube. An inverted U-shaped incision is made on second and third tracheal rings to raise a flap (Bjork flap). The tip of the flap is stitched to the inferior edge of the transverse skin incision (Fig. 16.9). Its advantage is that it prevents tube displacement and allows reintroduction of displaced tube with minimum difficulty.
Aftercare of Tracheostomy
i. Humidification: Warm, wet, oxygenated air is flown over the stoma to make tracheal secretions less viscid.
ii. Clearance of secretions: Intermittent suction is done at regular intervals to keep the tracheo-bronchial tree free from secretions. Strict asepsis should be maintained by keeping suction
Fig. 16.8: Elective tracheostomy—transverse skin incision Fig. 16.9: Bjork flap in elective tracheostomy
catheter in a sterile holder. The catheter is introduced with aseptic conditions after wearing mask and gloves.
iii. Clearance of thick mucus: When mucus is very thick and difficult to aspirate, isotonic saline, sodabicarb or mucolytic agent should be administered through the tracheostomy tube by a fine nebulizer. If there is inner tube, it should be removed and washed in sodabicarb solution.
iv. Care of cuff: Low pressure cuff should be used so that it does not occlude the mucosal circulation.
High pressure cuff can necrose the cartilage and can cause tracheal collapse.
v. Replacement of tube: Tube should be replaced every 3-4 days until a tract is established. During replacement one should be careful to place the tube correctly in tracheal lumen. A good airflow is apparent if the tube is in correct place.
Complications of Tracheostomy Intraoperative Complications
• Hemorrhage
• Recurrent laryngeal nerve injury
• Tracheal injury
• Esophageal injury
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Postoperative complications
• Surgical emphysema
• Pneumothorax
• Pneumomediastinum
• Aspiration pneumonia
• Accidental dislodgement of the tube
• Wound infection
• Tracheal stenosis
• Tracheo-esophageal fistula
• Tracheo-cutaneous fistula
• Tracheo-innominate artery fistula (severe hemor-rhage).
Fig. 16.10: Tracheostomy tube in position with tapes around patient’s neck