17. Pleural Effusion

Question 1

What is a pleural effusion and what is it caused by?

Answer 1

Is an excess of fluid in the pleural cavity

• Imbalance in the normal rate of pleural fluid production and absorption

Question 2

Where is pleural fluid produced from and how is it drained?

Answer 2

secreted by the parietal pleural and drained through the lymphatics of the parietal pleura

Question 3

What are different types of fluid that can build up in the pleura space?

Answer 3

• Simple Effusion: When the fluid is pleural fluid – can
be transudate or exudate
• Haemothorax: When the fluid is blood (e.g. trauma)
• Chylothorax: When the fluid is lymph (e.g. leak from lymphatic duct ..trauma)
• Empyema: When the fluid is pus (infective cause)

Question 4

What is the typical history of pleural effusions?

Answer 4

•  SOB (gradual onset)
•  Pleuritic chest pain
•  +/- features of underlying clinical disease
-- Congestive cardiac failure
-- Lung malignancy

Question 5

What are the respiratory examination results for pleural effusions?

Answer 5

• Trachea Deviation
Away from affected side
• Chest movement:
Reduced on affected side
• Percussion note:
"Stony" Dull on affected side
• Breath sounds:
(Vesicular) reduced /absent on affected side
• Vocal Resonance:
Reduced on affected side

Question 6

What are the radiological features of pleural effusions?

Answer 6

• fluid in dependent part (in upright position)
• dense that underlying markings not seen
• blurred diaphragm border
• upper border meniscus

Question 7

What is the treatment for pleural effusion?

Answer 7

• Treat the underlying condition

* In very symptomatic patients, chest aspiration might be indicated (thoracentesis)

Question 8

What treatment is indicated in recurrent pleural effusions?

Answer 8

• indwelling pleural catheter for intermittent drainage
OR
• Pleurodesis

Question 9

How is diagnosis of pleural effusion made?

Answer 9

• History
• Examination
• Radiology
• Diagnostic aspiration - best done under ultrasound guidance.

Question 10

What is the aspiration sent for?

Answer 10

 Protein levels
 Glucose levels
 LDH (lactate dehydrogenase)
 MC&S
 pH

Question 11

What will be found in pleural aspiration of transudate pleural effusion?

Answer 11

Serum Protein <0.5

The large protein molecules do not pass through the pores in the capillary

Question 12

What will be found in pleural aspiration of exudate pleural effusion?

Answer 12

Pleural:Serum Protein ≥0.5

Protein molecules pass through the ‘leaky’ capillary` - Increased capillary permeability due to inflammation

Question 13

What are the causes of transudate pleural effusion?

Answer 13

Things that increase fluid moving out vessels

• commonest cause is congestive heart failure
• hypoproteinaemia (cirrhosis, nephrotic syndromes) –> reduced oncotic pressure so water move out
• PE

Question 14

What are the causes of exudate pleural effusion?

Answer 14

• Infection - Pneumonia, TB
• Cancer (primary or secondary)
• Cancer may also block lymphatic drainage
• Pulmonary infarction