Chapter 28 - Pleural space disease Flashcards
Define the pleural space
Potential space formed by the parietal and visceral pleura which normally contains a small amount of serous fluid to facilitate movement of the lungs in relation to the thoracic cavity as well as to force distribution during normal breathing.
What is Starling’s Law applied to the pleural cavity?
K[(Pcparietal - Pcviscera)- Pintrapl] - (plasma intrapleural pressure - plasma oncotic pressure)
What determines the net pressure in the pleural space?
Visceral pleura, which favors reabsorption of fluid from the pleural space (including vascular supply and lower hydrostatic pressure)
What is the average pleural pressure?
-5cm H2O
What clinical sign has been strongly associated with pleural space disease in cats?
Paradoxical breathing
What radiographic view has the highest detection rate for small volume pneumothorax?
Left lateral recumbency with a left lateral view
Name 2 indications for thoracocentesis
for pleural effusion
Presence of undiagnosed pleural effusion, therapeutic thoracocentesis to relieve respiratory signs
Transudates are characterized by ____ total protein and ____ total nucleated cell count.
Low, Low
In an infectious process, what cell type predominates in an exudate?
Degenerate neutrophils
Describe FIP fluid:
viscous, straw colored, high protein concentration (>3.5g/dL), low nucleated cell count (<5000 cells/ mcL)
The most common bacteria isolated in a cat pyothorax.
Pasteurella
The most common bacteria isolated in a dog pyothorax.
E. coli and Enterobacteriacea
What is a concern with using sterile lavage for pyothorax?
Fluid overload from inflamed pleural tissue
What is the success rate of small animals treated with pyothorax?
~65%
What is the success rate of cats treated with pyothorax?
95% (medical management in cats fails 5-9% of the time)
In dogs, what has a better outcome with regards to treating a pyothorax- medical or surgical management?
Surgical management
In a chylous effusion, what is the main cell type?
Small lymphocyte
In a chylous effusion, what is the triglyceride concentration in comparison to serum?
Higher than in serum
In a chylous effusion, what is the cholesterol level in comparison to serum?
Equal to or less than serum
How does rutin work?
Bezopyrone neutraceutical that stimulates macrophage breakdown of protein in lymph to help accelerate reabsorption
What has become the most successful surgical procedure recommended for a chylothorax?
Thoracic duct ligation with subphrenic pericardectomy
Define a hemothorax.
Pleural space effusion with Hct > 10%
What is the most common cause of spontaneous hemothorax in the dog?
Neoplasia
Define fibrosing pleuritis.
Chronic condition where the visceral pleura becomes thickened and restricts lung expansion as a result of inflammation in the thoracic cavity
Difference between open and closed pneumothorax.
If it results from an insult to the thoracic wall = open, if thoracic cavity is intact and air originates from a lesion within the lung parenchyma = closed
Define tension pneumothorax.
if the site of air leakages creates a one way valve during inspiration and results in rapidly increasing pleural pressure
Traumatic pneumothorax has been found concurrently with what other diagnosis in dogs?
Pulmonary contusions, 47%
When is an exploratory thoracostomy indicated in a closed traumatic pneumothorax?
If it does not resolve after 3-5 days of drainage
What is considered a chronic DH?
Clinical signs present for more than 2 weeks
