Tracheostomy

Isthmus, thyroid ima artery and inferior thyroid veins are midline structures and thus can be injured during tracheostomy, more so during emergency tracheostomy. Inferior thyroid artery, a branch of the thyrocervical trunk of the subclavian artery lies laterally away from midline, thus can escape injury.

In emergency tracheostomy following structures can be damaged:

• Isthmus
• Inferior thyroid veins
• Thyroid ima artery
• Left brachio-cephalic vein, jugular venous arch
• Pleura (especially infants)
• Thymus
• Esophagus (the trachea is small, mobile, and soft in infants damage the esophagus)

Indications for tracheostomy are Flail chest, Head injury, Foreign body, Tetanus etc.

Cardiac tamponade is not an indication for tracheostomy.

Tracheostomy has also been divided into:

A) High tracheostomy: Done above level of thyroid isthmus. Indication is ca larynx.

B) Mid tracheostomy: It is the preferred one and done through II and III rings, division of isthmus.

Ans. is ‘a’ i.e., Most common early complication is subcutaneous emphysema; _b i.e., 3rd & 4th tracheal ring are incised

o In most of the cases tracheostomy is performed with general anaesthesia and the patient intubated and paralyzed. o Neck is extended.

o A horizontal incision is made halfway between the cricoid cartilage and the sternal notch.

• Subcutaneous fat and tissues are reflected, and deep cervical facia, is cut to expose thyroid isthmus.
• A vertical cut is given in 2-3 or 3-4 rings in midline and no part of the tracheal wall is removed.
• The endotracheal tube is withdrawn and a suitable size tracheostomy tube is simultaneously inserted.
• Post-operatively neck & chest radiograph are obtained to evaluate the position of the tube and to identify the subcutaneous emphysema & pneumothorax that could have developed as complication.

o Tube must be cleaned at frequent intervals.

o Patient should be nursed in and atmosphere of moist air.

A i.e. Flail chest; B i.e. Head injury; C i.e. Tetanus

Ans. is ‘b’ i.e. Tracheostomy 

Partial thyroidectomy is preferred over tracheostomy.

Ans. is ‘d’ i.e., All 

Ans. is ‘d’ i.e., In tracheostomy 

Carcinoma larynx presenting with stridor means it is subglottic laryngeal carcinoma .Ideally in such cases emergency laryngectomy should be performed.

But not done in cases if

• Intubation can not be done as growth is seen in subglottic area, therefore tube can not be put.
• Planned tracheostomy can not be done as patient is suffering from stridor, which is an emergency. Therefore we will have to do emergency tracheostomy. With the precaution that the area of cancer should be removed within 72 hours.

Historically, the main indication for a tracheostomy was to bypass upper airway obstruction caused by a foreign body or infection, particularly diphtheria.

Nowadays upper airway obstruction is the least common indicator for tracheostomy. Almost two thirds of tracheostomies are currently performed on intubated intensive care patients, mainly to aid removal of secretions from the distal tracheobronchial tree and to facilitate weaning from distal tracheobronchial tree in acute respiratory failure and prolonged ventilation

 It is important (in tracheostomy) to refrain from causing any damage in the region of cricoid cartilage.

An exception to this rule is when a patient has laryngeal malignancy and under these circumstances tracheostomy should be placed high so as to allow resection of tracheostomy site at the time of laryngectomy – Scott Brown 7th/ed vol 2 pg. 2295

The high tracheostomy is generally avoided because of the postoperative risk of peri-chondritis of the cricoid cartilage and subglottic stenosis. In cases of carcinoma larynx with stridor when total laryngectomy would be done, high tracheostomy is indicated.

A tracheostomy tube may be metallic or nonmetallic

• Metallic Tracheostomy Tube

Metallic tubes are formed from the alloy of silver, copper and phosphorus

Has an inner and an outer tube.The inner tube is longer than the outer one so that secretions and crusts formed in it can be removed and the tube reinserted after cleaning without difficulty. However, they do not have a cuff and cannot produce an airtight seal.

• Nonmetallic Tracheostomy Tube

Can be of cuffed or noncuffed variety, e.g. rubber and PVC tubes. 

Cuffed Tracheostomy Tubes

• A cuff is a balloon-like device around the distal end of the tracheostomy tube. Most cuffed tubes now available have low pressure cuffs with a high volume. This significantly reduces the possibility of pressure necrosis and potential stenosis formation. Pediatric tubes do not have a cufr. Cuffed tubes are used in situation where positive pressure ventilation is required, or when the airway is at risk from aspiration. (In unconscious patient or when patient is on respiration).

The cuff should be deflated every 2 hours for 5 mins to present pressure damage to the trachea.

Uncuffed Tracheostomy Tubes

This tube does not have a cuff that can be inflated inside the trachea.

It is suitable for a patient who has returned to the ward from a prolonged stay in intensive care and requires physiotherapy and suction via trachea.

This type of tube is not suitable for patients who are unable to swallow due to incompetent laryngeal reflexes, and aspiration of oral or gastric con­tents is likely to occur.

An uncuffed tube is advantageous in that it allows the patient to breathe around it in the event of the tube becoming blocked. Patients can also speak with an uncuffed tube.

 Complications of Tracheostomy

IMMEDIATE

Most common complication of tracheostomy is hemorrhage. The commonest cause of bleeding during tracheostomy is Anterior jugular vein.

Other Immediate Complication of tracheostomy

• Air embolism                                                                    • Apnea (due to sudden release of retained CO2)
• Cardiac arrest                                                                   • Local damage to structures
• Pneumothorax (d/t injury to apical pleura)

INTERMEDIATE

During first few hours or days

• Dislodgement/Displacement of the tube
• Surgical emphysema :May occur as the air may leak into the cervical tissues.

This is occasionally found in the immediate postoperative period.

Presents as a swollen area around the root of the neck and upper chest, which displays crepitus on palpation. It is due to overtight suturing of the wound and is not dangerous unless it leads to mediastinal emyphysema and cardiac tamponade.

• Pneumothorax/pneumomediastinum
• Tubal obstruction by Scabs/crusts
• Infection (tracheitis and tracheobronchitis, local wound infection).
• Dysphagia :

– This is fairly common in the first few days after tracheostomy.

– In normal swallowing a positive subglottic pressure is created by the closing of the vocal cords – which is why one cannot speak during swallowing.This is not possible with a tracheostomy tube in place, and thus swallowing is incoordinate. – Another reason for dysphagia is that if an inflatable cuff is blown up it will press on and obstruct the oesophagus.

• Tracheal necrosis
• Tracheo arterial (Tracheal innominate artery fistula) /Tracheoeshophageal fistula
• Recurrent laryngeal nerve injury.

LATE

• Hemorrhage due to erosion of major vessels
• Stenosis of the trachea (at the level of stoma)
• Laryngeal stenosis due to perichondritis of cricoid cartilage.
• Difficulty with decannulation
• Tracheocutaneous fistula/scars.

According to Scott-Brown’s 7th vol 2 p. 2301 – Tracheoarterial fistula / Tracheoesophageal fistula are intermediate complications and not late complications like tracheocutaneous fistula.

Aspiration is the passage of foreign material beyond the vocal cords:

• The larynx has 3 distinct functions – respiration, phonation and airway protection. Dysfunction of larynx can lead to aspiration.
• The primary goal of treatment of aspiration is to separate the upper digestive tract from the upper respiratory tract for a short period of time or in some cases, permanently.
• There are 3 broad categories of treatment.

Temporary/Adjunct Treatments

• Medical Therapy – in the form of antibiotics is important to prevent aspiration pneumonia.
• It is important to make the patient NPO, to avoid further aspiration and to find an alternate feeding route to maintain the patients nutritional status. A nasogastric tube (feeding gastostomy/jejunostomy) is commonly placed, but this may actually increase the aspiration reflux by making the lower esophageal and upper esophageal sphincters incompetent.

Vocal cord medialization (by injecting Gel foam) is useful in unilateral paralysis.This is helpful but is rarely curative, if there is a serious aspiration problem.

Tracheostomy will often make aspiration worse by preventing laryngeal elevation on swallowing. It does however, allow easy access to the chest for suctioning. Even a cuffed tube doesn’t prevent aspiration as secretions pool above the cuff and the seal is never perfect”- Scotts Brown 7th/ed vol 1 pg. 1278

Definite – Reversible Procedures

• Endolaryngeal stents: They function like a cork in the bottle. There job is to seal the glottis and therefore thay need to be used in conjunction with a tracheostomy tube. But they are not often used as they are effective only as a short term solution, plus there is risk of glottic stenosis.
• Laryngotracheal separation: The procedure involves transecting the cervical trachea and bringing out the lower end as a permanent end stoma
• But it has disadvantage of sacrificing voice.
• Alternative procedure is Tracheoesophageal diversion but has higher complication rates.

Definite – Irreversible Procedure

It includes: Narrow field laryngectomy: it was considered as a gold standard prior to 1970s, when the irreversible procedures like laryngo tracheal separation were not done.

Also Know

• Investigation of choice for diagnosing aspiration = Fibreoptic endoscopic evaluation of swallow (FESS)
• Videofluoroscopic modified Barium swallow (often called as ideofluoroscopy)

Infant’s larynx differs from adult in:

• It is situated high up (C2 – C4).Q (in adults = C3 – C6)
• Of equal size in both sixes (in adults it is larger in males)
• Larynx is funnel shaped
• The narrowest part of the infantile larynx is the junction of subglottic larynx with trachea and this is because cricoid cartilage is very small
• Epiglottis is omega shaped, soft, large and patulous.
• Laryngeal cartilages are soft and collapse easily
• Short trachea and short neck.

• Vocal cords are angled and lie at level of C4
• Trachea bifurcates at level of T2
• Thyroid cartilage is flat. The cricothyroid and thyrohyoid spaces are narrow.

Tracheostomy in Infants and Children                                                                                                              

Trachea of infants and children is soft and compressible and its identification may become difficult and the surgeon may easily displace it and go deep or lateral to it injuring recurrent laryngeal nerve or even the carotid.

During positioning, do not extend too much as this pulls structures from chest into the neck and thus injury may occur to pleura, innominate vessels and thymus or the tracheostomy opening may be made twoo low near suprasternal notch

Tracheostomy in Infants and Children                                                                                               

The incision is a short transverse one, midway between lower border of thyroid cartilage and the suprasternal notch. The neck must be well extended.

A incision is made through two tracheal rings, preferably the third or fourth.

Ans. B i.e. Difficult decanulation

Ans. D: Ideally should be changed every 3rd day

Inner cannula should be removed and cleaned as and when indicated for the first 3 days. Outer tube, unless blocked or displaced, should not be removed for 3-4 days to allow a track to be formed when tube placement will be easy.

Ans. B: Hemorrhage

To relieve upper airway obstruction

• Foreign body
• Trauma
• Acute infection – acute epiglottitis, diphtheria
• Glottic oedema
• Bilateral abductor paralysis of the vocal cords
• Tumours of the larynx
• Congenital web or atresia

– To improve respiratory function

• Fulminating bronchopneumonia
• Chronic bronchitis and emphysema
• Chest injury and flail chest
• Respiratory paralysis
• Unconscious head injury
• Bulbar poliomyelitis
• Tetanus
• Advantages of tracheostomy over endotracheal intubation
• Reduces patient discomfort
• Reduces need for sedation
• Improves ability to maintain oral and bronchial hygiene
• Reduces risk of glottic trauma
• Reduces dead space and reduces work of breathing
• Augments process of weaning from ventilatory support
• Complications of tracheostomy

– Immediate

• Haemorrhage
• Surgical trauma – oesophagus, recurrent laryngeal nerve
• Pneumothorax

– Intermediate

• Tracheal erosion
• Tube displacement
• Tube obstruction
• Subcutaneous emphysema
• Aspiration and lung abscess Late
• Persistent tracheo-cutaneous fistula
• Laryngeal and tracheal stenosis
• Tracheomalacia
• Tracheo-oesophageal fistula
• Post-operative tracheostomy care
• Maintain patent airway
• Frequent atraumatic suction
• Humidification of inspired air and oxygen
• Mucolytic agents
• Coughing and physiotherapy
• Occasional bronchial lavage
• Prevent infection and complications
• Aseptic tube suction, handling and tube changing
• Prophylactic antibiotics
• Deflate cuff for 5 minutes every hours
• Avoid tube impinging on posterior tracheal wall
• Percutaneous tracheostomy
• Indicated in patients likely to require ventilatory support for more than 2 weeks
• Usually performed at the bedside in an ITU
• Has significant cost benefits compared to open procedure

Ans. C: Emergency tracheostomy

Tracheostomy is an alternative when intubation is not possible

Tracheostomy:

• Double tube
• Made of titanium silver alloy
• In emergency trachesostomy, structure which can be injured are:

–        Inferior thyroid vein

–        Isthmus of thyroid

–        Thyroid imam artery

• Common complication is tracheal stenosis
• Mitomycin is used for tracheal stenosis

Ans. is ‘a’ i.e., Cricothyroid membrane

Cricothyrotomy or Laryngtomy or Minitracheostomy

• It is the procedure to open the airway through the cricothyroid membrane.
• Patient’s head and neck are extended, lower border of throid cartilage and cricoid ring is identified. Skin in this area is incised vertically and then cricothyroid membrane is opened with a transverse incision.
• It is an emergency procedure to buy time for the patient to be shifted to the operation theatre.