CAUSES – anything!
- Blood – post-op, trauma, malignancy, pulmonary infarct
- Exudate – parapneumonic effusion, empyema, subphrenic abscess, pancreatitis
- Transudate – increased hydrostatic pressure (heart and liver failure, fluid overload), decreased oncotic pressure (nephrotic syndrome, loosing protein), negative pleural pressure (atelectasis)
- Chyle
CXR FINDINGS (supine)
< 500mL
- homogenous density over lower lung zone
- veil appearance to lung
- lung markings not obliterated
- air bronchograms absent
500-3000mL
- silhouetting of diaphragm
- contralateral mediastinal shift >3000mL
- opacification of hemithorax
- contralateral mediastinal shift
PLEURAL FLUID
Things to put on the lab form:
- Protein
- LDH
- Glucose
- pH
- WCC
- Cytology
- Amylase
- HCT
- Gram stain
- Culture
Appearance
- straw coloured: normal
- blood: trauma, malignancy, pulmonary infarct, post pericardiotomy
- turbid: parapneumonic effusion or empyema
Protein
- PF:serum < 0.5 = transudate – PF:serum > 0.5 = extudate
LDH
- PF:serum < 0.6 = transudate – PF:serum > 0.6 = extudate
Glucose
- if less than half of serum: empyema, malignancy, RA, SLE
pH
- < 7.3 = empyema
WCC
- neutrophilia: parapneumonic effusion, empyema, PE
- lymphocytosis: Tb, RA, SLE, sarcoid, malignancy
Cytology
- malignancy
- mesothelial cells increased: mesothelioma
- mutinucleating giant cells: RA
Other
- chyomicrons and triglycerides: chylothorax
- amylase (PF > serum): ruptured oesophagus, pancreatitis, malignancy, bacterial pneumonia
- HCT > 0.5: haemothorax
Omg I just discovered the CCC section of this website. What an amazing website.