Page 95 - Problem-Based Feline Medicine

6 – THE CAT WITH HYDROTHORAX 87

Viral pneumonia mostly involves supportive treat- Systemic signs such as anorexia and weight loss (can-
ment. cer cachexia) are often present.
Supportive care includes airway and systemic Dull chest sounds and dyspnea result from pleural
hydration, which are essential for mucociliary clear- effusion.
ance. Intravenous crystalloids should be used judi-
ciously. Nebulization with saline may be helpful.
Diagnosis
Physical therapy including coupage, positional
drainage, position changes, etc., and oxygen enrich- Diagnosis is usually made by radiography followed by
ment are indicated. Bronchodilator therapy with beta biopsy via endoscopy, thorocolony or is ultrasound-
agonists such as terbutaline (0.625–1.25 mg PO q 12 guided.
hours) or methylxanthines such as sustained-release
Pleural effusion fluid is often a modified transudate
theophylline (Theo-Dur 25 mg/kg PO q 24 hours) may
and is often grossly opaque.
be helpful.
Thoracocentesis is rarely required for treatment, as the
parapneumonic pleural effusion generally resolves with Differential diagnosis
appropriate therapy for the pneumonia.
Other causes of pleural effusion such as congestive
heart failure and mediastinal masses may produce a
AIRWAY/PULMONARY NEOPLASIA similar type of effusion but are differentiated on radi-
ography, ultrasound and biopsy.
Classical signs
● Muffled heart and/or lung sounds ventrally. Treatment
● Exaggerated chest excursions with poor
Surgical resection via partial or total lobectomy is
airflow.
the treatment of choice for solitary primary neoplasms.
● Orthopnea (positional dyspnea with
Cure or long-term remission is possible with wide sur-
reluctance to lie in lateral recumbency).
gical margins. If non-resectible, excision of nodules
● Non-productive cough, with or without
may palliate clinical signs temporarily.
hemoptysis.
● Mass lesion seen radiographically. Chemotherapy and radiation have been attempted in
● Anorexia, weight loss, muscle wasting. generalized pulmonary neoplasms, with disappointing
results. Metastases from distant tumors carry a grave
See main reference on page 66 for details (The prognosis, although pulmonary lymphoma may attain
Dyspneic or Tachypneic Cat). remission with chemotherapy.

Clinical signs
HEMOTHORAX
Tracheal adenocarcinomas (i.e., Siamese), primary pul-
monary masses (pulmonary adenocarcinoma) or sec-
Classical signs
ondary metastatic disease from distant neoplasms may
create effusions. It is more common in middle-aged to ● Muffled heart and lung sounds ventrally.
older cats. ● Dyspnea characterized by excessive chest
excursions with poor airflow.
A non-productive cough may be present, with or without ● Orthopnea.
hemoptysis. Dyspnea (inspiratory and expiratory) and ● Pallor, possibly other sites of bleeding
reluctance to lie in lateral recumbency, or respiratory dis-
(epistaxis, hyphema, etc.).
tress is present if pleural effusion is of large volume.
Very rarely, lameness occurs from peripheral appendi- See main reference on page 493 for details (The Bleed-
cular bone lesions of hypertrophic osteopathy. ing Cat).