Pleural Effusion

Question 1

What is plural effusion

Answer 1

When fluid accumulates in pleural space

Question 2

Aetiology of pleural effusion

Answer 2

Transudate - Low protein content <30g/L
Exudate - High protein content >30g/L

Question 3

What causes transudate

Answer 3

Disturbances in oncotic pressure
- Cardiac failure
- Hypoproteinaemia
- Liver cirrhosis

Question 4

What causes exudate

Answer 4

Fluids that left circulatory system go into lesions/areas of inflammation, commonly due to infection or malignancy
- Pneumonia
- TB
- Connective tissue disease
- Asbestos

Question 5

Symptoms & signs of pleural effusion

Answer 5

Chest pain
Dry cough
SOB
Difficulty taking deep breath
Reduced chest expansion (affected side)
Stony dull percussion

Question 6

Investigations of pleural effusion

Answer 6

CXR
Aspiration of fluid (thoracentesis)
If diagnosis not clear from above = Pleural biopsy

Question 7

How much fluid needs to be present to be visible on CXR

Answer 7

> 500ml will cause a clear fluid level

Question 8

What is assessed in aspiration sample

Answer 8

Colour
Cytology
Microbiology
pH
Glucose

Question 9

What does straw coloured fluid indicate

Answer 9

Cardiac failure
Hypoalbuminemia

Question 10

What does bloody fluid indicate

Answer 10

Trauma
Malignancy
Infection
Infarction

Question 11

What does milky/turbid coloured fluid indicate

Answer 11

Empyema
Chylothorax

Question 12

What does foul smelling fluid indicate

Answer 12

anaerobic empyema(pus)

Question 13

What does fluid with food particles indicate

Answer 13

Oesophageal rupture

Question 14

What does bilateral fluid indicate

Answer 14

LVF
PTE
Drugs
Systemic path e.g. lupus

Question 15

What can cytology indicate

Answer 15

Lymphocytes indicate malignancy or TB
Neutrophils indicate an infection

Question 16

What happens in microbiology of fluid aspiration

Answer 16

• Gram stain
• Microscopy
• Culture
• PCR
• AFB stain

Question 17

What does the pH of fluid indicate

Answer 17

Normal = 7.6
>7.2 = simple effusion (pleural inflammation)
<7.2 = complicated effusion (requires drainage in infection setting)

Question 18

What does glucose of fluid indicate

Answer 18

Low in infection, TB, Malignancy, rheumatoid arthritis & oesophageal rupture

Question 19

Management of pleural effusion

Answer 19

Treat underlying disorder

Infection - simple effusion (pH >7.2) can be treated with antibiotics only, complicated effusion (pH <7.2) requires a chest drain and antibiotics