Page 76 - Problem-Based Feline Medicine

68 PART 2 CAT WITH LOWER RESPIRATORY TRACT OR CARDIAC SIGNS

Differential diagnosis Oronasal reflux, especially with fluids, occurs with
cleft palate.
Other causes of dynamic or fixed upper respiratory
tract obstruction are distinguished on laryngoscopic With stress, nasal obstruction may result in mouth
inspection (see Chapter 4, The Cat With Stridor). breathing.

Dynamic causes of upper respiratory tract obstruc-
tion are: Treatment
● Brachycephalic airway syndrome. This results in an
Treatment involves surgical correction of the defect, if
elongated soft palate causing partial laryngeal
possible.
obstruction and entrapment of the epiglottis, and
lateral ventricle eversion causing ballooning of the
mucosa of the lateral ventricles into the lumen. ACUTE SYSTEMIC ANAPHYLAXIS
● Cervical tracheal collapse.
● Pyogranulomatous or lymphoplasmacytic laryngitis Classical signs
results in a roughened, proliferative mucosa of the
● Acute dyspnea
arytenoids and epiglottis.
● Hypotensive shock
Fixed causes of upper respiratory tract obstruction are: ● Collapse
● Oropharyngeal neoplasia (squamous cell carci- ● Pale mucous membrances
noma, oral melanoma, nasopharyngeal polyp).
● Tracheal neoplasia (intraluminal adenocarcinoma, See main reference on page 566 for details (The Cat
extraluminal masses). With Polycythemia).
● Tracheal foreign bodies.
Clinical Signs
CONGENITAL ANOMALIES OF THE UPPER ● Pulmonary signs such as severe acute dyspnea
RESPIRATORY TRACT
predominate, because the lung is the “shock
organ” in cats.
Classical signs ● Signs of hypotensive shock, such as pallor and col-
● Dyspnea, usually fixed obstruction lapse, accompany the pulmonary signs.
(inspiratory and expiratory) due to stenotic ● The onset of clinical signs occurs in seconds to
nature of most defects. minutes after exposure to the inciting antigen.
● Inspiratory dyspnea and stertor occur with ● Occasionally, cutaneous swelling may be noted
the brachycephalic syndrome. around the face and paws.

See main reference on page 39 for details (The Cat Diagnosis
With Stridor).
● Diagnosis is made by a combination of appropri-
ate history and characteristic clinical signs.
Clinical signs ● No laboratory tests are currently available to
make a definitive diagnosis of acute systemic ana-
Stenotic nares, hypoplastic trachea, etc., potentially
phylaxis.
create a non-dynamic, fixed obstruction leading to
inspiratory and expiratory dyspnea, although inspira-
tory dyspnea may be more prominent with stenotic CARDIAC TUMORS
nares and hypoplastic trachea, if there is a dynamic
component to the obstruction. Classical signs
Dynamic obstructions such as occur with elongated ● Dyspnea and trachypnea.
soft palate create inspiratory dyspnea with stertor.