T2 L18: Pleural and chest wall disease

Cards (22)

  • What is the pleura?
    delicate serous membrane
    arranged as a sac
    enclosing the lungs at lines of the thoracic cavity
    • Visceral: covers surface of lungs and goes into fissures; attached directly to lungs
    • Parietal: lines inner chest wall
  • What is the intrapleural space and what are its properties?
    space between visceral and parietal pleura
    contains 10 to 20 mL of fluid as lubricant
    continuously produced and absorbed by the lymphatic system
  • What is pleural effusion?
    accumulation of fluid in intrapleural space exceeding physiological amounts (10-20mL)
    pathophysiology: changes in fluid & solute homeostasis. Mechanism determines if:
    • exudate (leaky vessels) or
    • transudate (intact vessel)
    may present as primary manifestation or secondary (complication)
  • What is the epidemiology of pleural effusion?
    relates to underlying disease thus present at all ages
  • What is the clinical presentation of pleural effusion?
    depends on fluid volume (small volume can be asymptomatic)
    symptoms: breathlessness, chest pain
  • How is pleural effusion diagnosed?
    Examination: dullness to percussion (stony dull) & decreased breath sounds
    Thoracic imaging: Chest X-Ray, CT, thoracic ultrasound, thoracocentesis, thoracoscopy, biopsy
  • What does this image show?
    chest X-ray
    left pleural effusion
  • What does this image show?
    CT thorax
    1. Pleural mass
    2. Loculated left pleural effusion
  • What does this image show?
    ultrasound
    pleural effusion
  • What is transudative pleural effusion?
    caused by fluid leaking through intact blood vessels
    causes:
    increased hydrostatic pressure (eg cardiac failure)
    decreased plasma oncotic pressure (eg liver cirrhosis)
  • What is exudative pleural effusion?
    Fluid accumulation in the pleural space due to inflammation or injury through leaky blood vessels / lymphatics
    Causes:
    • increased capillary permeability due to localised ruptures
    • decreased absorption eg lymphatic blockage
  • What is Light's criteria?
    for exudative effusion. Has 1 or more of:
    1. Pleural fluid protein/serum protein >0.5
    2. Pleural fluid LDH/Serum LDH > 0.6
    3. Pleural fluid LDH >2/3 the upper limit of normal of serum LDH
    98% sensitive and 83% specific
  • What are the possible causes of transudate pleural effusion?
    cardiac failure
    cirrhosis
    nephrotic syndrome
  • What are the possible causes of exudate pleural effusion?
    malignancy
    pneumonia
    tuberculosis
    mesothelioma
    rheumatoid arthiritis
  • What is pleural infection?
    bacteria enter pleural space:
    • direct eg pneumonia
    • indirect eg blood borne infection
    Confirmed on: microbiology, Light's criteria
    males more likely
  • What is empyema?
    severe pleural infection
    symptoms: breathlessness, chest pain, persistent fever
    Pleural tap:
    • appearance frank pus
    • pleural fluid pH <7.2
    • only 20% will get an organism
    Management: chest drain and antibiotics for at least 6 week
  • What is Haemothorax?
    blood in chest
    if occurs with pneumothorax: haemopneumothorax
    presents with breathlessness & chest pain
    history of trauma or malignancy
    treatment: chest drain & thoracoscopic surgery
  • What is Pneumothorax?
    air in intrapleural space
    primary spontaneous:
    • no underlying lung disease
    • age <50 years
    • no smoking history
    secondary spontaneous:
    • underlying lung disease
    • Age >50 years
    • Smoker
    symptoms: shortness of breath, chest pain
    Clinical features: reduced/no air entry on affected site, hyperresonant to percussions, tracheal shift (tension Px)
    Management: conservative, aspiration, chest rain
  • What is respiratory muscle weakness?
    Consequence of neuromuscular diseases (E.g. Amyotrophic lateral sclerosis, Guillian-Barre syndrome, Duchenne muscular dystrophy)
    Symptoms: nonspecific (fatigue, poor concentration, dyspnoea, orthopnoea)
  • How is respiratory muscle weakness examined?
    Physical examination: increased resp rate, alternate ribcage/abdominal breathing, accessory muscle use, unable to clear mucus, impaired swallow
    Pulmonary function testing: preserved total lung capacity, elevated residual volume, reduced vital capacity
  • How is respiratory muscle weakness managed?
    long-term non-invasive positive pressure ventilation
  • What is kyphoscoliosis?
    abnormal curvature of spine
    cause - various
    respiratory implications: restrictive lung defect / respiratory failure