Pleural effusion Flashcards
Which pleura produces the pleural fluid?
parietal pleura
Describe Light’s criteria
Pleural fluid is an exudate if one or more of the following is met:
- pleural fluid protein divided by serum protein is >0.5
- pleural fluid lactate dehydrogenase (LDH) divided by serum LDH is >0.6
- pleural fluid LDH >2/3 the upper limits of laboratory normal value for serum LDH
Causes of pleural transudates
left ventricular failure
liver cirrhosis
hypoalbuminaemia
peritoneal dialysis
hypothyroidism
nephrotic syndrome
mitral stenosis
constrictive pericarditis
urinothorax
Meig’s syndrome
Where do transudates normally affect and what is the treatment?
often bilateral but right side may be larger (pleural effusions)
treat the cause
Causes of pleural exudates
malignancy
parapneumonic effusions
tuberculosis
pulmonary embolism
RA/other autoimmune pleuritis
benign asbestos effusion
pancreatitis
post-myocardial infarction
post-coronary artery bypass graft
yellow nail syndrome
drugs
fungal infections
Which drugs can cause pleural effusions?
methotrexate
nitrofurantoin
amiodarone
phenytoin
beta blockers
How does a massive effusion show on a CXR?
white out
How can effusions often be seen on a CXR?
blunting of costophrenic and cardiophrenic angles
What do you need to know from the pleural fluid once it has been aspirated?
colour
protein, LDH, glucose
pH
gram stain, MC&S
cytology
Pleural effusion symptoms
dyspnoea
reduced exercise tolerance
chest pain
Pleural effusion signs
trachea central or deviated away from affected side (if large)
reduced chest expansion on affected side
stony dull percussion note on affected side
reduced/absent breath sounds over effusion, may have bronchial breathing at upper border of effusion
vocal resonance/tactile vocal fremitus reduced over effusion
What signs can give clues as to the cause of a pleural effusion?
pyrexia - infection
cachexia + clubbing - malignancy
raised JVP + ankle oedema - heart failure
Are transudative and exudative effusions more likely to be unilateral or bilateral?
exudative - unilateral
transudative - bilateral
What diagnostic test is needed for pleural effusions after a CXR?
ultrasound-guided thoracentesis for pleural fluid analysis
except for patients with clear evidence of heart failure (raised JVP, pitting ankle oedema, signs on CXR)
Management of pleural effusions
treat underlying cause
manage patient using ABCDE approach
oxygen therapy if needed
diuretics for heart failure, antibiotics for infection
ultrasound-guided pleural aspiration indicated if this fails or if the patient remains symptomatic from the effusion
intercostal drain - for large effusions or empyemas