Page 308 - Small Animal Internal Medicine, 6th Edition

280 PART II Respiratory System Disorders

given orally q12h initially) and cage rest may reduce the
secondary inflammation and edema of the pharynx and
VetBooks.ir larynx and enhance airflow, but it will not eliminate the
problem. Emergency therapy may be required to alleviate the
upper airway obstruction in animals presenting in respira-
tory distress (see Chapter 25).
Weight management and concurrent treatment for
gastrointestinal disease should not be neglected in patients
with brachycephalic airway syndrome.

Prognosis
A The prognosis depends on the severity of the abnormalities
at the time of diagnosis and the ability to surgically correct
them. Clinical signs will progressively worsen if the underly-
ing problems go uncorrected. The prognosis after early surgi-
cal correction of the abnormalities is good for many animals.
Laryngeal collapse is generally considered a poor prognostic
indicator, although even dogs with severe laryngeal collapse
can respond well to surgical intervention (Torrez et al.,
2006). Permanent tracheostomy can be considered as a
salvage procedure in animals with severe collapse that are
not responsive. A hypoplastic trachea is not surgically cor-
rectable, but there is no clear relationship between the degree
B of hypoplasia and morbidity or mortality. Using the objective
measurement of tracheal diameter:thoracic inlet distance,
six English Bulldog puppies (2-6 months of age) had improve-
FIG 18.2
Cat with severely stenotic nares (A) as compared with the ment in relative tracheal diameter when reevaluated radio-
nares of a normal cat (B). Early correction of stenotic nares graphically after 6 months or longer (Clarke et al., 2011).
and other amenable upper airway obstructions, such as an These findings suggest partial resolution is possible in some
elongated soft palate, is highly recommended. puppies as they develop.

OBSTRUCTIVE LARYNGITIS
Treatment
Therapy should be designed to enhance the passage of air Nonneoplastic infiltration of the larynx with inflamma-
through the upper airways and to minimize the factors tory cells can occur in dogs and cats, causing irregular
that exacerbate clinical signs (e.g., excessive exercise and proliferation, hyperemia, and swelling of the larynx. Clini-
excitement, overheating). Surgical correction of anatomic cal signs of an upper airway obstruction may result. The
defects is the treatment of choice. The specific surgical larynx may appear grossly neoplastic during laryngoscopy
procedure selected depends on the nature of the existing but is differentiated from neoplasia on the basis of the his-
problems and can include widening of the external nares topathologic evaluation of biopsy specimens. Inflamma-
and removal of excessive soft palate and everted laryn- tory infiltrates can be granulomatous, pyogranulomatous,
geal saccules. Laser turbinectomy has proven success- or lymphocytic-plasmacytic. Etiologic agents have not been
ful in improving quality of life but is technically difficult identified.
and not readily available (Schuenemann and Oechtering, This syndrome is poorly characterized and probably
2014). includes several different diseases. Some animals respond
Correction of stenotic nares is a simple procedure and can to glucocorticoid therapy. Prednisone or prednisolone
lead to a surprising alleviation of signs in affected patients. (1 mg/kg given orally q12h) is used initially. Once the
Stenotic nares can be safely corrected at 3 to 4 months of age, clinical signs have resolved, the dose of prednisone can
ideally before clinical signs develop. The soft palate should be be tapered to the lowest amount that effectively maintains
evaluated at the same time and corrected if elongated. Such remission of clinical signs. Conservative excision of the
early relief of obstruction should decrease the amount of tissue obstructing the airway may be necessary in animals
negative pressure placed on pharyngeal and laryngeal struc- with severe signs of upper airway obstruction or large
tures during inspiration and may decrease progression of granulomatous masses.
disease. The prognosis varies, depending on the size of the lesion,
Medical management consisting of the administration of the severity of laryngeal damage, and the responsiveness of
short-acting glucocorticoids (e.g., prednisone, 0.5 mg/kg the lesion to glucocorticoid therapy.