Indications
The cricoid split operation is an operation aimed at widening the
airway sufficiently to permit the extubation of babies and small
children with developing subglottic stenosis.
The cricoid cartilage is the only complete ring of cartilage in the
skeleton of the airway and is also its narrowest point. If the child
has required ventilating for some time, the mucous membrane within the
cricoid cartilage can become very swollen and inflamed and become
squashed between the wall of the tube and the unyielding cricoid
cartilage. This can give rise to scarring causing subsequent subglottic
stenosis. The cricoid split operation is intended to release this
pressure on the mucous membrane to give it a chance to recover without
narrowing the airway.
Anaesthetic
The operation is performed under general anaesthetic.
Technique
A horizontal incision is made across the midline of the lower neck.
The cricoid cartilage is exposed and a vertical incision is made in the
airway, cutting the cricoid cartilage and sometimes the upper rings of
the trachea. The wound is then closed with a drain.
Length of Operation
About half an hour. Postoperative, the endotracheal tube is left in place for 7 to 10 days.
Time in Hospital
This is unpredictable because it will depend upon the child's general condition.
Outcome
Results of cricoid split operation vary. It would be expected to
permit the extubation of at least 50 % of the children who have the
operation and thereby save the need for a tracheostomy.
Risks & Complications
Surgical emphysema in which air leaks out of the incised
cricoid and builds up under the skin because it can not vent to the skin
surface. This is usually prevented by adequate drainage.
Fistula - A permanent connection between the airway and the skin surface is a rare complication.
Alternative Treatments
It is frustrating to be unable to remove a ventilating tube from a
child who no longer needs it. Sometimes a further period of waiting and
extubation a few days later may be successful particularly if steroids
are given to reduce any swelling of the subglottic mucous membrane. The
other alternative treatment is the performance of a tracheostomy to
bypass the blockage in the upper airway. This is still necessary in
some cases and it is to avoid the need for tracheostomy that the cricoid
split operation was first developed.