Pleural effusion

Question 1

List the five mechanisms for pleural effusion

Answer 1

1. Increased venous/capillary hydrostatic pressure
2. Decrease capillary oncotic pressure
3. Increased capilallary membrane permeability
4. Lymphatic obstruction
5. Spillage/haemothorax

Question 2

What should be included on fluid evaluation of pleural effusion

Answer 2

1. Gross - colour/turbidity
2. Protein determination/specific gravity
3. Cell count
4. Cytology
5. Fluid pH
6. Blood glucose
7. Culture and sensitivity WHERE indicted.

Question 3

List radiographic changes that may support pleural effusion

Answer 3

1. Fissure lines - fluid filled interlobar fissure lines
2. Separation of lung borders from thoracic wall
3. Blurred/lost cardiac/diaphragm borders
4. Mediastinum - widened.
5. Costophrenic angle - blunting of lung margins
6. Air bronchograms
7. Rounding of lung lobes.
   (Fuzzy scarecrows butcher mysterious chivalrous bratwursts mercilessly)

Question 4

List characteristics of transudate

Answer 4

Colour: colourless to pale yellow,
Turbidity: clear
Protein; <2.5g/dL
Triglyceride or Nuc cells; Absent, <1500.
Cytology; mesothelial cells, lymphocytes, macrophages, and rare non degenerate neutrophils.

Question 5

Differential diagnosis for transudate as pleural effusion

Answer 5

Early CHF, hypoalbuminemia.

Question 6

Characteristics of modified transudate

Answer 6

Colour: yellow to pink to orange
Turbidity; clear to slightly cloudy
Protein 2.5-7.5g/dL
Nuc cell count; 1000-7000. 
Cells are macrophages, mesothelial cells, non-degenerative neutrophils.

Question 7

List differential diagnosis for modified transudate

Answer 7

Chronic CHF, neoplasia, diaphragmatic hernia, SIRS eg pancreatitis,

Question 8

List characteristics for non-septic exudates

Answer 8

Colour; yellow or pink to orange. 
Turbidity - cloudy. 
protein >3G/dL, >4.5g/dL in FIP
Cell count - >7000
Cytology; non degenerate PMN, macrophages

Question 9

List differentials for non-septic exudates

Answer 9

FIP
Neoplasia
Lung lobe torsion
Tissue inflammation

Question 10

List characteristics for septic exudates

Answer 10

Colour; yellow to orange to tan
Cloudy to turbid
Nuc cell counts; >7000.
Degenerative neutrophils, some macrophages.

Question 11

List characteristics of chylous exudates.

Answer 11

Colour - white/milky,
Turbidity; opaque
Protein; 2.5-6.9 g/dL.
Triglycerides are present/higher than blood stream
Cell types; small lymphocytes, some macrophages, nondegenerate neutrophils, plasma cells.

Question 12

List differentials for chylous exudates

Answer 12

Chylothorax; obstructed or ruptured thoracic duct, Heart worm, neoplasia, CHF, lung lobe torsion, trauma.