Pleural effusion Flashcards
if a pleural aspiration showed a protein content between 25-30g/l how would you differentiate whether it was exudate or transudate?
Light’s criteria
exudate is likely if one of the following;
- if pleural fluid LDH divided by serum LDH > 0.6
- if pleural fluid LDH 2/3 of upper limit of normal
- if pleural fluid protein divided by serum protein > 0.5
what the pathophysiology of transudate vs exudate pleural effusions?
transudate:
- imbalance of hydrostatic forces
- protein content < 30g/l
- causes include LVF, hypoalbuminaemia (liver failure, nephrotic syndrome), hypothyroidism
exudate:
- increase in permeability of pleural sac and/or capillaries
- protein content > 30g/l
- causes include pneumonia, malignancy, autoimmune (RA, SLE), PE, dressler’s syndrome, pancreatitis
what lab investigations should pleural aspiration fluid be sent for?
LDH
protein
PH
cytology and microbiology
a pleural fluid with low glucose is suggestive of what cause?
rheumatoid arthritis
TB
a pleural fluid with raised amylase is suggestive of what cause?
pancreatitis
oesophageal perforation
a pleural fluid stained heavy with blood is suggestive of what cause?
mesothelioma
PE
TB
how is a pleural effusion managed?
pleural aspiration
- USS recommended as it reduces likelihood of complications
- 21G needle and 50ml syringe
- fluid sent for microbiology, cytology, protein, PH, LDH
what are possible causes of a bilateral pleural effusion?
bilateral most commonly transudate
- LVF
- hypoalbuminaemia (liver failure, nephrotic syndrome)
- hypothyroidism
- meig’s syndrome
what are possible causes of a unilateral pleural effusion?
unilateral most commonly exudate
- infection (pneumonia, TB, subphrenic abscess)
- malignancy (lung cancer, mesothelioma, metastasis)
- autoimmune (SLE, RA)
- pancreatitis
- Dressler’s syndrome
- pulmonary embolism
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