• Pneumocystis Jirovecii (see Pneumocystis Jirovecii, [[Pneumocystis Jirovecii]])
    • Physiology: rupture of pneumocyst into pleural space
  • Septic Embolism
    • Epidemiology: case reports (Thorax, 1992) [MEDLINE]
  • Tuberculosis (see Tuberculosis, [[Tuberculosis]])
    • Epidemiology: xxx
    • Physiology: rupture of cavity into pleural space

Trauma/Surgery/Procedure-Related Pneumothorax

  • Bronchoscopy (see Bronchoscopy, [[Bronchoscopy]])
    • Bronchoalveolar Lavage (BAL): very low risk of pneumothorax
    • Transbronchial Biopsy (TBB): higher risk of pneumothorax than with BAL
  • Central Venous Catheter Placement (see Central Venous Catheter, [[Central Venous Catheter]])
    • Physiology: inadvertent puncture of pleural space during procedure
    • Clinical Data
      • French Multi-Center, Randomized Trial Examining Complication Rates of Three Different Central Venous Catheter Insertion Sites (NEJM, 2015) [MEDLINE]: multi-center, randomized trial (n = 3471)
        • Subclavian CVC had 3x Higher Risk of Pneumothorax Requiring Chest Tube Insertion (1.5% of Cases), as Compared to Internal Jugular Sites (0.5% of cases)
  • Chest Trauma
    • Blunt Thoracic Trauma (see Blunt Thoracic Trauma, [[Blunt Thoracic Trauma]])
    • Penetrating Thoracic Trauma
  • Crack Cocaine Abuse (see Cocaine, [[Cocaine]])
    • Physiology: forceful inhalation and/or breath-holding
  • Forceful Coughing (see Cough, [[Cough]])
  • Inadvertent Placement of Nasogastric/Orogastric Tube Into the Pleural Space (see Nasogastric-Orogastric Tube, [[Nasogastric-Orogastric Tube]])
  • Mechanical Ventilation (se eMechanical Ventilation-General, [[Mechanical Ventilation-General]])
    • Physiology: barotrauma
  • Methamphetamine Intoxication (see Methamphetamine, [[Methamphetamine]])
    • Physiology: xxx
  • Parathyroidectomy (see Parathyroidectomy, [[Parathyroidectomy]]) (J Surg Educ, 2007) [MEDLINE]
  • Thoracentesis (see Thoracentesis, [[Thoracentesis]])
    • Physiology
      • Inadvertent Introduction of Air Via Needle
      • Puncture of Lung During Procedure
  • Tracheobronchial Fracture (see Tracheobronchial Fracture, [[Tracheobronchial Fracture]])
  • Tracheostomy (see Tracheostomy, [[Tracheostomy]])
    • Physiology
      • Inadvertent Extraluminal Positioning of the Tracheostomy Fenestration During Tracheostomy Placement: for this reason, fenestrated tracheostomies are typically not selected for initial percutaneous tracheostomy placement
      • Laceration of the Posterior Tracheal Wall
    • Clinical

Connective Tissue/Autoimmune Disease

  • Rheumatoid Arthritis (RA) (see Rheumatoid Arthritis, [[Rheumatoid Arthritis]])
    • Physiology: rupture of necrobiotic nodule into pleural space
  • Scleroderma (see Scleroderma, [[Scleroderma]])
    • Physiology: xxx
  • Ankylosing Spondylitis (see Ankylosing Spondylitis, [[Ankylosing Spondylitis]])
    • Physiology: due to rupture of apical bullae



  • Birt-Hogg-Dube Syndrome (see Birt-Hogg-Dube Syndrome, [[Birt-Hogg-Dube Syndrome]])
    • High-Resolution Chest CT (HRCT) (see High-Resolution Chest Computed Tomography, [[High-Resolution Chest Computed Tomography]]): cystic lung lesions occur in 70-80% of cases
    • Clinical: pneumothorax may occur in 30% of cases, usually before age 40 (see Pneumothorax, [[Pneumothorax]])
  • Bullous Emphysema with Ruptured Bleb (see Chronic Obstructive Pulmonary Disease, [[Chronic Obstructive Pulmonary Disease]])
    • Bleb is an intrapleural air collection (therefore, it is a form of interstitial emphysema)
    • Bleb can develop in newborns or in the setting of ventilator-associated barotrauma
  • Cryptogenic Organizing Pneumonia (see Cryptogenic Organizing Pneumonia, [[Cryptogenic Organizing Pneumonia]])
    • Epidemiology: rarely presents with pneumothorax
  • Idiopathic Pulmonary Fibrosis (IPF) (see Idiopathic Pulmonary Fibrosis [[Idiopathic Pulmonary Fibrosis]])
    • Epidemiology: xxx
    • Physiology: xxx
  • Langerhans Cell Histiocytosis (LCH) (see Langerhans Cell Histiocytosis, [[Langerhans Cell Histiocytosis]])
    • Epidemiology: xxx
  • Lymphangioleiomyomatosis (LAM) (see Lymphangioleiomyomatosis, [[Lymphangioleiomyomatosis]])
    • Epidemiology: xxx
    • Physiology: xxx
  • Neurofibromatosis (see Neurofibromatosis, [[Neurofibromatosis]])
    • Epidemiology: xxx
  • Pneumomediastinum (see Pneumomediastinum, [[Pneumomediastinum]])
    • Physiology: air dissects from mediastinum into pleural space
  • Sarcoidosis (see Sarcoidosis, [[Sarcoidosis]])
    • Epidemiology: xxx
  • Spontaneous Pneumothorax


Path of Air Movement Between Anatomic Spaces

  • Mediastinum <-> Left and Right Pleural Space (Pneumothorax)
  • Mediastinum <-> Neck Soft Tissues (Subcutaneous Emphysema)
  • Mediastinum <-> Peritoneum (Pneumoperitoneum)

Etiologies of Various Pleural Space Pressure States


Pleural Fluid (see Thoracentesis, [[Thoracentesis]])

  • Pleural Eosinophilia: may be seen -> eosinophils appear within 3 days and peak at day 6

Thoracic Ultrasound (see Thoracic Ultrasound, [[Thoracic Ultrasound]])

  • Sensitivity: very sensitive in detecting pneumothorax and can be repeated at bedside multiple times, noninvasively, and quickly
  • Sliding Sign: normal finding, where the visceral pleura slides against the parietal pleura
    • In pneumothorax, “sliding” is absent
  • Lung Point Sign: where, in the presence of pneumothorax, the lung touches the chest wall intermittently

Clinical Manifestations

Cardiovascular Manifestations

  • Hypotension: may occur with tension pneumothorax
  • xxxx

Pulmonary Manifestations

Unilateral or Bilateral Pneumothorax

  • Physiology
  • Diagnosis
    • Unilateral Pneumothorax
    • Bilateral Pneumothorax: may occur in cases with “buffalo chest” (where mediastinum has been previously entered during prior mediastinal surgery, lung transplant, etc) (see Buffalo Chest, [[Buffalo Chest]])
  • Clinical


  • ACCP Recommendation: observation for small spontaneous PTX (<3 cm rim on CXR) and clinical stability
  • BTS Recommendation: observation for small spontaneous PTX (<2 cm rim on CXR) and clinical stability
  • Pleurodesis: recommended for patients with second ipsilateral spontaneous pneumothorax


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