PNEUMOTHORAX


I. Primary spontaneous pneumothorax
  1. Defined as pneumothorax occurring in the absence of trauma or clinically apparent lung disease
  2. May be related to subpleural blebs that then rupture
  3. Peak incidence is between 10-30yo; rare after 40yo
  4. Right lung involved more than left; 10-15% of cases are bilateral
  5. Pleural effusion can occur in 10-20% of pts
  6. Risk factors include priori primary spontaneous pneumothorax (recurrence rate is 30% on same side within 2y), cigarette smoking, tall body habitus, and family history
    1. Abrupt onset of ipsilateral sharp pleuritic chest pain and dyspnea, usually while at rest
    2. 10% of cases are asymptomatic; others may have relatively mild symptoms
    3. Px shows tachycardia and, on the affected side, decreased chest wall movement with breathing, hyperresonance to percussion, diminished tactile fremitus, and decreased or absent breath sounds
    4. Clinical symptoms do not correlate well with size of pneumothorax
  7. Management
    1. Analgesia
    2. High-flow oxygen (may help resolve pneumothorax due to favoring the diffusion of nitrogen out of pleural space and into blood)
    3. OK to discharge if clinically stable, small pneumothorax not expanding after 6h, if prompt f/u for worsening sx can be assured
    4. If pt has large pneumothorax or is clinically unstable, requires treatment
    5. Options for treatment
      1. Aspiration of intrapleural air with 16-18g needle inserted w/local anesthesia, connected to suction if necessary (or one-way Heimlich valve)
      2. 24-28 French chest tube (for large air leaks and/or failure of smaller chest catheters)
      3. Surgical consult if improvement not seen within 48h
      4. Avoid air travel for 6wks after resolution
      5. Avoid diving permanently unless gets bilateral surgical pleurectomy
      6. Consider CT to determine location of any subpleural blebs to allow for surgical treatment to reduce risk of recurrent pneumothoraces (e.g. thoracoscopic resection and pleurodesis, or chemical pleurodesis with tetracycline or talc for nonsurgical candidates)
II. Secondary spontaneous pneumothorax
  1. Defined as pneumothorax occurring in the absence of trauma but in the presence of clinically apparent lung disease
  2. Can be life-threatening
  3. Associated with COPD, Pneumocystic jirovecii pnuemonia in HIV-positive patients, cystic fibrosis, pulmonary tuberculosis, asthma, necrotizing pneumonia, connective tissue diseases, and pulmonary malignancies.
  4. Peak incidence is 60-65yo
  5. Usually presents with ipsilateral chest pain and dyspnea; physical findings (see above) may be obscured by underlying lung disease
  6. Management should include hospital admission; can be treated with high-flow oxygen + observation if clinically stable and pneumothorax is small but otehrwise should receive drainage with chest tube
  7. Because morbidity and mortality are greater than with primary spontaneous pneumothorax, and incidence of recurrence is high (50%), definitive treatment is more commonly advised after a first episode (thoracoscopic resection of blebs with pleural abrasian; pleurodesis through a chest tube is an alternative but is associated with greater recurrence rates).

(Sources include Core Content Review of Family Medicine, 2012)