Pleural effusion is the accumulation of fluid in the pleural space (which is in the thoracic cavity)
It can cause clinical signs such as anorexia or hyporexia, difficulty breathing, and lethargy among others
There are many possible types and causes of effusion
Some possible types include: transudate, modified transudate, chylothorax, pyothorax, or hemothorax
Some possible causes include: congestive heart failure, low protein levels (hypoproteinemia), cancer, feline infectious peritonitis, trauma, lung lobe torsion, diaphragmatic hernia, among others
Because there are so many possible types and causes, it is very important to remove the fluid (thoracocentesis) so it can be analyzed and characterized. This procedure can be both therapeutic and in some cases, diagnostic.
The prognosis depends on the cause but is usually guarded
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