Lecture 17- Pleural effusion

Question 1

In normal pleural cavity there is tightly controlled

Answer 1

production and absorption of pleural fluid.

Question 2

pleural cavity lined by

Answer 2

mesothelial cells

Question 3

pleural fluid is absorbed by the

Answer 3

lymphatic stoma

Question 4

• Excess fluid in the pleural cavity

Answer 4

Imbalance between rate of production and absorption

Question 5

types of pleural effusion

Answer 5

• simple effusion
• haemothorax
• chylothorax
• empyema

Question 6

Simple effusion:

Answer 6

when there is fluid in the pleural fluid- can be transudate or exudate

Question 7

transudate

Answer 7

occurs due to icnrease hdyrostatic pressure and low onctoic pressure

i.e. low protein and LDH

Question 8

exudate

Answer 8

occurs due to ifnlamamtiona nd icnreased capillary permeability

i.e. fluid is high protein and LDH

Question 9

Haemothorax: §

Answer 9

when the fluid is blood e.g. trauma

Question 10

Chylothorax:

Answer 10

when the fluid is lymph (e.g. leak from lymphatic duct)

Question 11

Empyema:

Answer 11

when the fluid is pus (secondary to resistant infection)

Question 12

Presenting symptoms and signs

*

Answer 12

• SOB (gradual onset)
• Pleuritic chest pain – irritation of pleural lining to the fluid e.g. blood or lymph
• Features of clinical disease
  
  • Congestive cardiac failure – pulmonary oedema
  • Lung malignancy

Question 13

Signs

Answer 13

• Trachea deviation
  
  • Away from the affected side
• Chest movement
  
  • Reduced on affected side
• Percussion notes
  
  • Stony dull on affected side
• Breath sounds
  
  • (Vesicular) reduced/ absent on affected side
• Vocal resonance
  
  • Reduced on affected side

Question 14

radiological findings: CXR and CT

Answer 14

Meniscus showing fluid in the pleural cavity (right base)

• Beneath the yellow line= fluid

Question 15

causes of a simple effusion

Answer 15

• Pleural fluid
  
  • Transudate or exudate
• Investigations
  
  • Pleural aspiration
    
    • USS guided procedure
  • Pleural fluid should be colourless

Question 16

causes

Haemothorax:

*

Answer 16

when the fluid is blood

• Trauma
• After pleural aspiration
  
  • Red

Question 17

causes Chylothorax

Answer 17

when the fluid is lymph (e.g. leak from lymphatic duct

• Trauma
• After pleural aspiration
  
  • Cloudy

Question 18

causes of Empyema

Answer 18

when fluid is pus

• infective cause
• After pleural aspiration
  
  • Hard to tell
    
    • Send fluid off for:
      
      • Protein levels
      • Glucose levels
      • LDH (lactate dehydrogenase)
      • MC and S
      • pH <7

Question 19

Treatment

Answer 19

• Depending on the cause
• In very symptomatic pts: chest aspiration

Question 20

• Recurrent effusions (particularly malignant) may require

Answer 20

Indwelling pleural catheter (IPC) for intermittent drainage

Pleurodesis

Aim to allow adequate oxygenation of the lungs for the rest of the body

Question 21

Pleurodesis

Answer 21

obliteration of the pleural space

Question 22

main causes of transudate in simple efussion

Answer 22

congestive cardiac failure

• Hypoproteinaemia
  
  • Nephrotic syndrome
  • Liver cirrhosis

Question 23

main causes of exudate in simple efussion

Answer 23

infection (TB, pneumonia), lung malignancy, pulmonary infarction

Question 24

lights criteria of transudate vs exudate

Answer 24

Question 25

**In general….Transudate**

Answer 25

**- reduced protein (albumin** * Reduced oncotic pressure * More water leaks out of capillaries and into potential spaces such as pleural cavity

Question 26

**In general…. Exudate**

Answer 26

**- normal protein (albumin)** * Protein’s molecules pass through leaky capillary * Due to inflammation