Brachycephalic airway syndrome, Part 2: Veterinary surgery of the soft palate and larynx

source-image
May 01, 2012

EDITOR'S NOTE: SurgerySTAT is a collaborative column between the American College of Veterinary Surgeons (ACVS) and DVM Newsmagazine.

Brachycephalic airway syndrome is described in dogs and cats that have brachycephalic conformation—a short, wide head. The primary components of the syndrome are stenotic nares, an elongated soft palate and a hypoplastic trachea (most often seen in English bulldogs). All these features can be present, or the presence and severity of each component can vary. The result is altered airway pressures.

In the first article in this series, which appeared in the April 2012 issue of DVM Newsmagazine, I reviewed your options for correcting stenotic nares. Here I discuss the options and prognosis for fixing soft palate and laryngeal abnormalities.

Elongated soft palate


Figure 1: The caudal margin of the tonsillar crypt (red arrows). Note the amount of soft palate caudal to this level and that it is entrapping the epiglottis. (All photos courtesy of David Saylor, VMD, VCA Veterinary Referral Associates, 500 Perry Parkway, Gaithersburg, Md.)
Elongation of the soft palate causes clinical signs when the palate contacts the epiglottis or extends past the caudal margin of the tonsils (Figures 1 and 2). Clinical signs (other than respiratory signs) include gagging, and sometimes the gagging will induce vomiting.


Figure 2: The soft palate passes over the epiglottis (same patient as in Figure 1) and moves into and obstructs the lumen of glottis.
Two landmarks are used to guide resection of the palate. The palate is resected to the level where it barely contacts the epiglottis or even by envisioning an imaginary line connecting the caudal margin of the tonsillar crypts. Palate resection can easily be accomplished by using scissors, a laser or a vessel-sealing device (LigaSure—Covidien).


Figure 3: The appearance of the resected soft palate site when a vessel-sealing device (LigaSure) is used. The appearance is similar to that resulting from laser procedures.
Scissor resection (often referred to as "cut-and-sew") requires mucosal closure with suture apposing the nasal mucosal surface to the oral mucosa. A fine (4-0 or smaller), rapidly absorbing suture is usually used in a simple continuous appositional pattern. Laser and LigaSure techniques do not require suturing, but sutures can be used (Figure 3).

Avoidance of excessive carbonization with the laser is imperative. Swelling, hemorrhage, overshortening and dehiscence are potential complications. Swelling and hemorrhage are the most concerning as they can cause severe airway obstruction. Overshortening can cause nasal reflux of oral contents into the caudal nasopharynx, but this is rarely seen clinically, especially if the landmarks are used (Figure 1).