Page 147 - Manual of Equine Field Surgery

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CHAPTER 24

Tracheostomy

David A. Wilson

aspect of the trachea. The smaller sternothy-
INDICATIONS roideus inserts on the caudal border and abaxial

surface of the thyroid cartilage, and the larger

Tracheostomy is indicated for any permanent dis- sternohyoideus continues on to insert on the

order of the larynx and upper trachea in which basihyoid bone. The paired omohyoideus muscles

airflow is impaired. originate from the subscapular fascia close to the

shoulder joint and join the sternohyoideus iI1 the

proximal third of the neck. The trachea primarily

EQUIPMENT consists of from 48 to 60 hyaline cartilage rings.

These rings are (-shaped and open dorsally, with

No special equipment is required. Self-retaining the ends connected by the transversely oriented

retractors and Rochester Carmalt forceps or tracheal muscle.1

similar forceps are desirable.

PROCEDURE

POSITIONING AND PREPARATION

Several similar techniques have been described.i"

The surgery can be performed with the horse A 10- to 12-cm ventral midline incision is made

standing with mild sedation and local anesthesia in the proximal third of the neck in a region where

or in dorsal recumbency under general anesthe- the trachea is palpable (Figure 24-1). If a tra-

sia. The head should be extended for either pro- cheotomy has been performed previously, this site

cedure. If the procedure is performed in dorsal should be avoided.

recumbency, care should be taken to position the The cutaneous colli and subcutaneous tissues

neck, head, and body without twisting or torquing are incised, and the paired sternothyrohyoideus

such that the skin incision is directly on midline and omohyoideus muscles are identified. The

when the horse stands. The ventral cervical region right and left sternothyrohyoideus muscles are

is clipped and prepared routinely for aseptic separated on midline and retracted laterally to

surgery. expose a section of three or four tracheal rings.

Sections of the paired sternothyrohyoideus

muscles as well as the most axial portions of the

ANATOMY omohyoideus muscles are clamped with an

angiotribe, straight Rochester- Pean or Rochester-

The paired sternothyrohyoideus muscles originate Carmalt forceps, transected, and excised at the

from manubrium sterni and extend on the ventral proximal and distal extent of the tracheostomy

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