Page 196 - Clinical Manual of Small Animal Endosurgery

184 Clinical Manual of Small Animal Endosurgery

Fig. 6.8 Multiple small pulmonary metastases, demonstrating a rosette
appearance, on lateral thoracoscopy in a flat-coated retriever.

Exploratory thoracoscopy and biopsy have also been found diagnostic
in all canine and feline pleural effusion cases in which it was performed
(Kovak et al., 2002), and thus extremely useful in determining the prog-
nosis and suitable treatment protocol in cases of pleural effusion.
Exploratory thoracoscopy can also be used with lavage for the diag-
nosis and treatment of pyothorax. Johnson and Martin (2007), however,
demonstrated that even chronic cases of pyothorax with adhesions
respond extremely well to conservative medical treatment with a single
pleurocentesis, no lavage and 6 weeks broad-spectrum antibiosis. Enthu-
siasm for endosurgery should not encourage one to perform thoracos-
copy unnecessarily in these cases, and it should be directed only to those
chronic cases that are not responsive to medical treatment, and the ones
demonstrating pulmonary masses or consolidation. In these cases the
surgeon should be prepared to perform a partial or complete lung lobec-
tomy should this be necessary, if a foreign-body granuloma, abscess or
neoplasia is found. Adhesiolysis of multiple strong fibrous adhesions can
be time-consuming and care needs to be taken not to injure the lungs
and other tissues. The ultrasonic scalpel, in the form of either a dissecting
hook or shears, is better suited to pleural adhesiolysis than the monopo-
lar hook or scissors.
Exploratory thoracoscopy is useful in cases of recurrent spontaneous
pneumothorax. Emphysematous bullae (Brisson et al., 2003) or isolated
lung lesions can be treated by ligation with extracorporeal loop ligatures
or other means. Cases with no obvious bullae or other gross abnormali-
ties are more difficult, and saline instillation may help in locating an air
leak, by visualisation of bubbles during ventilation.
In cases with no obvious gross pathology, biopsies should be taken of
pleura, lung, lymph nodes, pericardium and mediastinum. Biopsies of