Empyema

Collection of pus in the pleural space, usually evolving from a parapneumonic effusion. These progress in three phases:

Technically, an empyema is a collection of pus in any space, but the generic, unqualified empyema refers to an infected pleural collection.

  1. Uncomplicated parapneumonic effusion
    Exudate without neutrophils:
    • Common
    • Resolves with resolution of pneumonia, very few will require drainage

An uncomplicated parapneumonic effusion is not infected and therefore not an empyema, but provides a foundation for an up-and-coming infective collection.

  1. Uncomplicated exudative effusion
    Exudate with neutrophils, i.e. pus.
  2. Complicated exudative effusion
    Exudate with neutrophils and organisms present.
  3. Loculated collection
    Infected, walled-off collections limit amenability of percutaneous drainage.

Epidemiology and Risk Factors

Pathophysiology

Aetiology

Clinical Features

Assessment

History:

Exam:

Investigations

Bedside:

Laboratory:

  • Pleural fluid
    • Gram stain
    • Culture

Imaging:

  • Lung ultrasound
    • Loculations
    • Thickened pleura
  • Contrast CT
    • Loculations
    • Enhancing pleura

Other:

Diagnostic Approach and DDx

Management

  • Standard sepsis management
    Covered under Management.
  • Procedural drainage
  • Adjunctive antibiotics

Resuscitation:

Specific therapy:

  • Pharmacological
    • Antibiotics
      • Prolonged therapy (2-6 weeks) generally required
      • Treatment identical to the the causative pneumonia, with consideration for tissue penetration
  • Procedural
  • Physical
    • Drainage
      • Percutaneous
        First-line therapy. Options (in ascending order of invasiveness), include:
        • Thoracocentesis
          In-and-out drainage of a collection.
          • Avoids prolonged drain and risk of discomfort and infection
          • Recollection may occur
          • Most appropriate for uncomplicated effusions causing respiratory impairment
        • Fine-bore drain
          Seldinger placement of a small (10-14Fr) catheter.
          • Well tolerated
          • Bedside procedure
          • Definitive in most unloculated collections
          • May become blocked
          • May become dislodged
        • Radiological drainage
          • Guided drainage of loculated collections
          • May require multiple drains
        • Wide-bore drain
          Placement of a wide-bore ICC via thoracostomy.
          • Bedside procedure
          • Provide option of digital decortication during placement
            Breaking septa of loculated collections with finger.
          • Less well tolerated compared to fine-bore drains
          • Not substantially more effective than fine-bore drains
      • Surgical
        Definitive technique for drainage of loculated or complicated collections.
        • VATS drainage
          • Allows reasonably thorough drainage of all collections
          • Requires GA and OLV
          • Pain
        • Decortication
          Removal of infected pleural tissue.
          • May be open or VATS
          • Significant pain
        • Thoracotomy
          • Allows thorough drainage of all loculated collections
          • Requires GA and OLV
          • Significant pain

Supportive care:

Disposition:

Preventative:

Marginal and Ineffective Therapies

Anaesthetic Considerations

Complications

Prognosis

Key Studies

References