Tracheostomy (氣管造口術)

A tracheostomy is an artificial opening made into the trachea. It may be created after the larynx has been removed, when it is permanent, or when the larynx is still in place, when it is usually temporary.

Indications:

• Total laryngectomy
• Airway protection, e.g. after major head and neck surgery, neurological disease involving the larynx
• Airway obstruction, e.g. epiglottitis, bilateral recurrent laryngeal nerve palsy, tumour
• Respiratory insufficiency (when endotracheal intubation required for longer than 72h) e.g. severe chest wall injury, Guillain-Barre syndrome

Surgical technique:

• Incision, horizontal, midway between the cricoid cartilage and suprasternal notch.
• Vertical incision and separation of strap muscles.
• Transfixion and separation of thyroid isthmus.
• Creation of an opening into the trachea. In adults a window is cut out. A vertical slit incision is used in children. A trap-door flap should not be used.
• Insertion of tracheostomy tube. A correctly sized cuffed synthetic tube is used for the first 24h. this can be replaced later on by an uncuffed tube.

Complications:

• Immediate. Pneumothorax, haemorrhage, surgical emphysema and tube displacement can all occur.
• Early. Wound infection, dysphagia and tube obstruction are all common. Tracheal erosion with innominate artery rupture, perichondritis and apnoea in hypercapnoeic bronchitics are rare.
• Late. Tracheal stenosis may result from prolonged or overinflation of the cuffed tube. Decannulation may be difficult in children. Surgical closure of a persistent tracheocutaneous fistula is rarely required after decannulation. 

Stomal stenosis (造瘻口狹窄) Aetiology:Following laryngectomy the lower end of the trachea is brought out through the neck skin. Local wound infection, radiotherapy and keloid formation all predispose to the later development of a stomal stenosis. The other cause of stomal stenosis is recurrence of tumour.

Management:

Management of benign stomal stenosis is either by the permanent wearing of a stoma button or laryngectomy tube or by surgical revision of the stoma.