Pleural effusion

Question 1

Types of pleural effusion?

Answer 1

Transudative
Exudative

Question 2

Causes of transudative pleural effusion?

Answer 2

Heart failure
Cirrhosis
Nephrotic syndrome
Hypoalbuminaemia
Hypothyroidism
Meigs syndrome

Question 3

What is Meigs syndrome?

Answer 3

Triad of ovarian fibroma, pleural effusion and ascites

Question 4

Causes of exudative pleural effusion?

Answer 4

Malignancy
Infection - pneumonia, TB
Pulmonary embolism
Rheumatoid arthririts
SLE
Pancreatitis
Trauma

Question 5

What is the difference in protein level for exudative and transudative pleural effusion?

Answer 5

Exudative >30g/L

Transudative < 30g/L

Question 6

Is pleural effusion causing restrictive or obstructive lung disease?

Answer 6

Restrictive

Question 7

How to confirm whether pleural effusion if transudative or exudative?

Answer 7

Light’s criteria. 3 criteria involved, if any one is POSITIVE = exudative. If not = TRANSUDATIVE

Question 8

What are the three Lights criteria for pleural effusion?

Answer 8

Effusion to serum protein ratio >0.5

Effusion to serum LDH ratio >0.6

If effusion LDH is 2/3 above the ULN of serum LDH.

Question 9

Mechanism of exudative pleural effusion?

Answer 9

Inflammation causing release of cytokines (proteins) into pleural space

Question 10

Mechanism of transudative pleural effusion?

Answer 10

Drop in oncotic or increased in hydrostatic pressure

Question 11

Symptoms and signs of pleural effusion?

Answer 11

SOB

Signs: reduced breath sounds
dull percussion
Tracheal deviation away from affected side if very large effusion
Loss of vocal fremitus over effusion

Question 12

X ray signs of pleural effusion?

Answer 12

Blunting of costophrenic angle
Fluid in lung fissures
Meniscus indicates large effusion
Tracheal deviation away from affected side

Question 13

Investigations for pleural effusion?

Answer 13

CXR

Pleural tap

Pleural biopsy if pleural fluid analysis does not reveal a diagnosis

Paired serum protein and LDH

Blood glucose - low in effusions secondary to RA, SLE, empyemas

Complement - low in RA, SLE effusions
VBG - pH is low in exudative

Haematocrit - if blood seen in pleural tap, need to distinguish it from haemothorax.

Tests for underlying cause, e.g. urinalysis if nephrotic syndrome

Question 14

Management of pleural effusion?

Answer 14

Conservative (if small effusion):
Symptomatic
O2
ABCDE approach

Medical:
if infection -> antibiotics
If empyema -> drainage
Diuretics if HF

Interventional:
Pleural aspiration to drain fluid
Chest drain if larger effusion, empyemas and haemothorax, to drain fluid
If recurring effusion: pleurodesis, tunnelled indwelling pleural drain.