Pleural Effusion

CAUSES – …just about 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


< 500mL

  • homogenous density over lower lung zone
  • veil appearance to lung
  • lung markings not obliterated
  • air bronchograms absent


  • silhouetting of diaphragm
  • contralateral mediastinal shift >3000mL
  • opacification of hemithorax
  • contralateral mediastinal shift


Things to put on the lab form:

  • Protein
  • LDH
  • Glucose
  • pH
  • WCC
  • Cytology
  • Amylase
  • HCT
  • Gram stain
  • Culture


  • straw coloured: normal
  • blood: trauma, malignancy, pulmonary infarct, post pericardiotomy
  • turbid: parapneumonic effusion or empyema


  • PF:serum < 0.5 = transudate – PF:serum > 0.5 = extudate


  • PF:serum < 0.6 = transudate – PF:serum > 0.6 = extudate


  • if less than half of serum: empyema, malignancy, RA, SLE


  • < 7.3 = empyema


  • neutrophilia: parapneumonic effusion, empyema, PE
  • lymphocytosis: Tb, RA, SLE, sarcoid, malignancy


  • malignancy
  • mesothelial cells increased: mesothelioma
  • mutinucleating giant cells: RA


  • chyomicrons and triglycerides: chylothorax
  • amylase (PF > serum): ruptured oesophagus, pancreatitis, malignancy, bacterial pneumonia
  • HCT > 0.5: haemothorax

References and Links

CCC 700 6

Critical Care


Chris is an Intensivist and ECMO specialist at the Alfred ICU in Melbourne. He is also a Clinical Adjunct Associate Professor at Monash University. He is a co-founder of the Australia and New Zealand Clinician Educator Network (ANZCEN) and is the Lead for the ANZCEN Clinician Educator Incubator programme. He is on the Board of Directors for the Intensive Care Foundation and is a First Part Examiner for the College of Intensive Care Medicine. He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives.

After finishing his medical degree at the University of Auckland, he continued post-graduate training in New Zealand as well as Australia’s Northern Territory, Perth and Melbourne. He has completed fellowship training in both intensive care medicine and emergency medicine, as well as post-graduate training in biochemistry, clinical toxicology, clinical epidemiology, and health professional education.

He is actively involved in in using translational simulation to improve patient care and the design of processes and systems at Alfred Health. He coordinates the Alfred ICU’s education and simulation programmes and runs the unit’s education website, INTENSIVE.  He created the ‘Critically Ill Airway’ course and teaches on numerous courses around the world. He is one of the founders of the FOAM movement (Free Open-Access Medical education) and is co-creator of litfl.com, the RAGE podcast, the Resuscitology course, and the SMACC conference.

His one great achievement is being the father of three amazing children.

On Twitter, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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