Page 63 - Problem-Based Feline Medicine

5 – THE DYSPNEIC OR TACHYPNEIC CAT 55

Muffled heart and lung sounds ventrally, dull chest Clinical signs
percussion.
Pyothorax is more common in intact males and is likely
Depending on the etiology of the effusion, signs of associated with fight wounds.
chronic illness may be present such as weight loss.
Dull or muffled heart and lung sounds are audible ven-
Inappetence or anorexia and pyrexia may be present
trally.
with pyothorax.
Marked chest wall excursions with minimal airflow are
Diagnosis evident, and dyspnea is worsened by lateral recumbency
(orthopnea).
With mild to moderate clinical signs, thoracic radiogra-
The cat typically has a sick, septic, thin, unkempt
phy may be diagnostic. Signs are evident when fluid
appearance and may be febrile.
exceeds 50 ml/kg.
With severely affected cats in respiratory distress, radi- Diagnosis
ography should be delayed until after thoracocentesis.
A thick, fetid, septic, suppurative exudate is obtained
● CATS WITH PLEURAL EFFUSIONS DIE IN
on thoracocentesis. Cytology and Gram stains reveal
RADIOLOGY!
many degenerate neutrophils, some with intracellular
Fluid analysis is essential to determine etiology. bacteria. Culture and sensitivity should be performed,
but may show no growth of organisms.
Differential diagnosis
Hemothorax, transudation from increased hydrostatic
ACUTE AND CHRONIC INFECTIOUS UPPER
pressure (cardiac disease) or decreased oncotic pres-
RESPIRATORY TRACT DISEASE**
sure (protein-losing enteropathies, nephropathies or
hepatic disease), lymphatic obstruction (thoracic neo-
Classical signs
plasia), chylothorax and pyothorax are all forms of
hydrothorax that need to be differentiated. ● Acute or chronic nasal discharge (bilateral,
copious, mucopurulent).
● Open-mouth breathing.
Treatment
● Coughing.
Thoracocentesis is part of the universal therapy for all ● Ocular discharge.
forms of pleural effusion. ● +/- Nasal distortion.

Definitive therapy is based upon the underlying cause.
See main reference on page 19 for details (The Cat
With Signs of Chronic Nasal Disease) and page 5 (The
Cat With Acute Sneezing or Nasal Discharge).
PYOTHORAX**

Classical signs Clinical signs
● Dyspnea related to pleural effusion. Upper respiratory tract disease may cause inspiratory
● Signs of chronic disease (weight loss, dyspnea as a result of nasal obstruction.
inappetence).
Signs may be acute and associated with calici or herpes
● +/- Fever.
virus infection or chronic associated with cryptococco-
● Turbid, flocculent and other fetid-smelling
sis, neoplasia or chronic secondary bacterial rhinitis
pleural fluid.
following calici or herpes viral infection.
See main reference on page 75 for details (The Cat When dyspnea is present, nasal discharge is usually
With Hydrothorax). bilateral, often mucopurulent and copious.