The cause of laryngeal obstruction should be treated but, if obstruction is acute and endangering the patient's life, urgent intervention is necessary. In most cases the insertion of an endotracheal tube either through the nose or mouth, and down the pharynx through the larynx to bypass the obstruction, is effective (see ENDOTRACHEAL INTUBATION). If not, tracheostomy is performed. The majority are undertaken as part of intensive care when it proves necessary over a prolonged period to provide mechanical ventilation so as to avoid damage to the lining of the traches from the presence of a tube.

Tracheostomy may also be performed for large tumours which obstruct the larynx until some form of treatment is instituted. Similarly it may be needed in conditions whereby the nerve supply to the larynx has been jeopardised, impairing its protective function of the upper airway.

When the trachea has been opened – by an incision through the skin between the Adam's apple and the clavicles; another through the THYROID GLAND followed by a small vertical incision in the trachea – a metal or plastic tube is inserted to maintain the opening. There is always an outer tube which is fixed in position by tapes passing round the neck, and an inner tube which slides freely within the former, so that it may be removed at any time for cleansing, and is readily coughed-out should it happen to become blocked by mucus.

When the operation has been performed for some permanent obstruction, the tube must be worn permanently; and the double metal tube is in such cases replaced after a short time by a soft plastic single one. When the operation has relieved some obstruction caused, say, by diphtheria, the tube is left out at intervals for a few hours, and finally, at the end of a week or so, is removed altogether, after which the wound quickly heals up.