Pleural Effusion

Question 1

What are possible differentials for pleural space disease?

Answer 1

(Pleural effusion, pleural space/mediastinal mass, diaphragmatic hernia, and pneumothorax)

Question 2

What can cause a pneumothorax?

Answer 2

(Leaking air from the lung d/t trauma or secondary to lung dz or thoracic wall penetration)

Question 3

Describe a pure transudate based on the following parameters:

• Protein
• TNCC
• Cytology
• Appearance
• Possible causes

Answer 3

• Protein (< 2.5 g/dL)
• TNCC (Low, <1500 nucleated cells/uL)
• Cytology (Mostly macrophages with low numbers of neutrophils, lymphocytes, and mesothelial cells)
• Appearance (Colorless to light yellow, transparent)
• Possible causes (Increased venous pressure, lymphatic hypertension, or low oncotic pressure)

Question 4

Describe a modified transudate based on the following parameters:

• Protein
• TNCC
• Cytology
• Appearance
• Possible causes

Answer 4

• Protein (2.5-7 g/dL)
• TNCC (1,000-7,000 cells/uL)
• Cytology (Mostly macrophages and neutrophils, low numbers of lymphocytes and mesothelial cells)
• Appearance (Light to moderate yellow, may be blood tinged, transparent to slightly cloudy)
• Possible causes (Increased venous or lymphatic pressure, inflammation of pleural vasculature; pure transudates can become modified with chronicity)

Question 5

Describe a exudate based on the following parameters:

• Protein
• TNCC
• Cytology
• Appearance
• Possible causes

Answer 5

• Protein (>3 g/dL)
• TNCC (> 7,000 cells/uL)
• Cytology (Neutrophils predominate, low numbers of macrophages and a few lymphocytes)
• Appearance (Purulent appearance, foul odor)
• Possible causes (Infectious)

Question 6

Describe a hemorrhagic effusion based on the following parameters:

• Protein
• TNCC
• Cytology
• Appearance
• Possible causes

Answer 6

• Protein (Usually > 2.5 g/dL)
• TNCC (Variable, >0.5-1 million/uL - - RBC with a measurable PCV)
• Cytology (Many RBCs)
• Appearance (Looks like blood)
• Possible causes (Coagulopathy, bleeding neoplasia, or trauma)

Question 7

Describe a chylous effusion based on the following parameters:

• Protein
• TNCC
• Cytology
• Appearance
• Additional testing recommendations
• Possible causes

Answer 7

• Protein (Usually > 2.5 g/dL)
• TNCC (Variable)
• Cytology (Small lymphocytes predominates with low numbers of large/reactive lymphocytes, macrophages and neutrophils may contain numerous discrete marginated vacuoles in their cytoplasm)
• Appearance (White to pink, opaque)
• Additional testing recommendations (Run a triglycerides, should be > 100 mg/dL and/or >2x serum)
• Possible causes (Cardiac dz, idiopathic, neoplasia, heartworm, cranial vena cava thrombus or mass)

Question 8

What are the medical management options for idiopathic chylous pleural effusion?

Answer 8

(Periodic thoracocentesis, low fat diet (meant to reduce intestinal lymphatic flow), and rutin (given to enhance protein removal and phagocytosis of chyle))