The larynx

Tracheostomy

What is“Tracheostomy” Tracheostomy is making an opening in the anterior wall of the trachea and converting it into a stoma on the skin surface.

Surgical anatomy 

Trachea is situated normally in the midline The trachea is more superficial at its upper end About 7-8 cartilaginous rings constitute the cervical portion In children: neck is shorter, larynx is higher and trachea is more superficial.

TracheotomyRelative anatomy

Function of tracheostomy

1- Alternative pathway for breathing. 2- Improve alveolar ventilation. In cases of respiratory insufficiency, alveolar ventilation is improved by: A- Decreasing the dead space by 30-50% (normal dead space is 150 ml). Dead space is air that is inhaled by the body in breathing, but does not take part in gas exchange. B- Reducing the resistance to airflow. 3- Protects the airway: By using cuffed tube, tracheobronchial tree is protected against aspiration of: A- Pharyngeal secretions, as in case of bulbar paralysis or coma. B- Blood in haemorrhage from pharynx, larynx or maxillofacial injuries.

4- Permits removal of tracheobronchial secretions. * Unable to cough in coma * When cough is painful, as in chest injuries 5- Intermittent positive pressure respiration (IPPR). If IPPR is required beyond 72 hours, tracheostomy is superior to intubation. 6- To administer anaesthesia in cases where endotracheal intubation is difficult as in laryngopharyngeal growths or trismus.

Types of Tracheostomy

Elective temporary tracheostomy Planned procedure, usually under GA, in head and neck surgery as safety measure. Permanent tracheostomy: e.g. bilateral abductor paralysis, advanced laryngeal cancer laryngectomy Emergency tracheostomy: When there is urgent need to establish the airway. It is usually done under local anaesthesia.


Surgical techniques
Position of the patient

Incision

Separate the strap muscles of the neck


Thyroid isthmus is pushed up or down or cut & a piece of tracheal ring is removed from 3rd and 4th

Tracheostomy tubes:

1- The Silver Jackson tube: this is used for temporary tracheostomy and consists of A- Outer tube B- Inner tube which can be cleaned without disturbing the outer tube. C- Introducer. It is metallic tube and its use is contraindicated in case of radiotherapy

2- Portex tube: cuffed uncuffed types. There is no inner tube They are almost non-irritant. Its use is safe during radiotherapy

Post-operative care

Constant supervision Suction Prevention of crusts and tracheitis Care of tracheostomy tube.

Complication of tracheostomy

1- Apnoea: this follows opening of trachea in a patient who had prolonged respiratory obstruction. This is due to sudden washing out of CO2 which was acting as a respiratory stimulus. Treatment is to administer 5% CO2+95% O2 or covering of tracheostomy opening by plastic bag.


2- Subcutaneous surgical emphysema: due to escape of air around the tube. It may be due to small tube or tight suturing of the wound. Air spread on the subcutaneous plane to face, neck or arms. Treatment: open the skin widely and put appropriate size tube.

3- Blockage of the tube, due to lack of humidification or poor toilet. Treatment; change the tube remove the crusts by bronchoscopy.

4- Slipping of tube where the tube lies in the cellular tissue in front of the trachea. It is due to small tube or low tracheostomy.

5- Failure of decannulation: overcome by progressive occlusion of the tube or use of smaller and smaller tubes. Tube is blocked 24 hours before removal. If the patient can sleep, eat and walk without dyspnoea then the tube can safely be removed.

Trachea-cutaneous fistula.

Intubation Versus Tracheostomy
Intubation is easier than tracheostomy, no anaesthesia, no wound and complications are less. Tracheostomy is more difficult and takes longer time. In any patient who needs intubation for more than 3 days, tracheostomy must be done for him.

Tracheostomy

Intubation
Takes longer time
Quick procedure
Time
Less specialized facilities
Needs specialized I.C.U due to the risk of obstruction and dislodgement.
Nursing
Possible by closing the tube
Impossible
Talking and coughing
Normal
By NGT
Feeding
Not necessary
Necessary
Sedation

Tracheostomy

Intubation
Complications
Positive
Negative
Pneumothorax and surgical emphysema
Positive
Negative
Scar
Less dangerous
Dangerous
Dislodgement
Less common
Common
Obstruction