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

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

References and Links


CCC 700 6

Critical Care

Compendium

Chris is an Intensivist and ECMO specialist at The Alfred ICU, where he is Deputy Director (Education). He is a Clinical Adjunct Associate Professor at Monash University, the Lead for the  Clinician Educator Incubator programme, and a CICM First Part Examiner.

He is an internationally recognised Clinician Educator with a passion for helping clinicians learn and for improving the clinical performance of individuals and collectives. He was one of the founders of the FOAM movement (Free Open-Access Medical education) has been recognised for his contributions to education with awards from ANZICS, ANZAHPE, and ACEM.

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

On Bluesky, he is @precordialthump.bsky.social and on the site that Elon has screwed up, he is @precordialthump.

| INTENSIVE | RAGE | Resuscitology | SMACC

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