Page 142 - Manual of Equine Field Surgery

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CHAPTER 23

Tracheotomy

David A. Wilson

INDICATIONS ANATOMY

Indications for tracheotomy are to establish an The paired muscle bellies of the sternornandib-

emergency airway because of an upper airway ularis, sternothyroideus, and sternohyoideus mus-

obstruction, or to relieve nasal or laryngeal cles lie on the ventral aspect of the trachea and are

inflammation. Tracheotomy is a life-saving proce- separated during the approach. The tracheal rings

dure i11 the face of an upper respiratory obstruc- are spaced closely together, but incision of the

tion. Tracheotomy is also used to "rest" an annular ligament allows enough separation

inflamed upper respiratory tract. Tracheotomy to insert the tracheotomy tube without removal

can also be used as a route for endotracheal intu- of portions of the tracheal ring (Figures 23-1

bation for general anesthesia when nasotracheal through 23-5).

or orotracheal intubation limits access to the sur-

gical field.

PROCEDURE

EQUIPMENT

A 6- to 8-cm ventral midline incision is made

Tracheotomy tube and scalpel blade. between the tipper and middle thirds of the neck

in a region where the trachea is easily palpable. In

cases where a permanent tracheostomy is antici-

POSITIONING AND PREPARATION pated or even a possibility, the tracheotomy site

should be caudal enough to allow space in the

Ideally, a wide area is clipped and routinely pre- cranial third of the neck for the subsequent tra-

pared for aseptic surgery; however, i11 emergency cheostomy (Figure 23-6). Long incisions should

situations little preparation is done. The proce- be avoided to improve the "fit" of the tracheotomy

dure is ideally performed standing with the head tube.

extended using local anesthesia. In an emergency The subcutaneous tissues are incised, and the

situation, a variety of positions are used. When paired sternothyrohyoideus muscles are separated

used as a route for endotracheal intubation, the on midline. Blunt dissection should be minimized

procedure is often performed iI1 lateral recum- to decrease subcutaneous emphysema and seroma

bency after induction of anesthesia. Light seda- formation. Two tracheal rings in the center of the

tion may be necessary for fractious patients. incision are identified, and a transverse stab inci-

Draping is not necessary, but sterile instruments sion is made between the two rings. The stab inci-

and gloves are desirable. sion should completely penetrate the tracheal

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