Print Friendly, PDF & Email

Pneumothorax

­­

 

Definition of a pneumothorax

  • Air in the pleural space leading to lung deflation. Pneumothoraces can be divided into:
    • Primary: otherwise “normal” lung
    • Secondary: underlying lung disease e.g. COPD
    • Tension: mediastinal shift and respiratory compromise

 

Epidemiology of pneumothoraces

  •  Approximately 10 per 100,000
  • Male>Female (6:1)
  • > 40 years often associated with COPD
  • Smoking increases the risk of pneumothorax

 

Causes of pneumothoraces

  • Spontaneous/ Primary
    • Thought to be due to congenital weakness of a pleural bleb
  • Secondary
    • COPD, Asthma, Lung cancer, Pulmonary Fibrosis, TB, Sarcoid, CF, PCP
    • Marfans, Ehlers Danlos, Psuedoxanthoma elasticum
  • Iatrogenic
    • Pleural aspiration or biopsy
    • CVP or pacemaker insertion
    • CPR
  • Chest trauma
    • Penetrating chest injury
      • Tension pneumothorax is more likely in this group
  • Intubation and ventilation
    • Especially with high pressures used

 

Presentation of a pneumothorax

  • Pleuritic chest pain and shortness of breath
    • (but note may be asymptomatic)
  • Signs:
    • Tachycardia and tachypnoea
    • Cyanosis
    • Tracheal deviation
    • Hyper-resonance to percussion
    • Decreased breath sounds
    • In tension pneumothorax:
      • Raised JVP, pulsus paradoxus, marked tracheal deviation, Tachycardia >135, hypotension, distended neck veins

 

https://www.youtube.com/watch?v=j_UGBS-Kp2I

 

Differential diagnosis of a pneumothorax

  • Pleural effusion
  • PE
  • Pneumonia
  • Pericarditis

 

Investigation of a pneumothorax

  • ABG
    • Hypoxia, severity dependent on size of pneumothorax and respiratory reserve
  • CXR
    • Will show characteristic rim around outside of lung
    • Size can be estimated by depth of rim at hilum
      • 2cm is approximately equal to 50% lung volume lost
    • In supine films, look for deep costophrenic sulci, darkened lung field and prominent heart border.
  • USS Chest
    • Can be helpful to look for iatrogenic pneumothorax following US guided drain insertion/ pleural biopsy
  • CT
    • Can detect occult pneumothoraces
    • Can be useful to differentiate bullae from pneumothorax
    • To look for causes of persistent leak in patients with non-resolving pneumothorax

 

Staging of pneumothorax

  • Small vs Large
    • > 2cm rim between lung margin and chest wall at the level of the hilum

 

Management of a pneumothorax

  • Observation In small primary pneumothorax without significant shortness of breath.
  • Patients with primary or secondary pneumothorax and significant breathlessness should undergo active intervention

 

Further management of a pneumothorax

  • Surgical
    • Those with persistent air leak at 48 hours should be discussed with thoracic surgeons.
    • Surgical management options include:
      • Open thoracotomy and pleurectomy (give lowest recurrence rates)
      • VATs with pleurectomy and pleural abrasion (better tolerated)
      • Surgical chemical pleurodesis
  • Medical pleurodesis
    • Considered for patients refusing/ not fit enough for surgery
  • Ambulatory management with Heimlich valve
  • Smoking cessation

 

Treatment of tension pneumothorax (a medical emergency):

  • High-flow oxygen
  • Emergency needle decompression
    • Large cannula, second intercostal space (just above third rib), mid-clavicular line
    • Converts tension to a simple pneumothorax
  • Followed by chest drain insertion for definitive management

 

 

Complications of pneumothoraces

  • Respiratory failure
  • Conversion to tension pneumothorax
  • Bronchopleural fistula
  • Recurrence

 

Prognosis in pneumothorax

  • Good if treated but recurrence is common: up to 30% overall.
  • Mortality low, but increased in secondary versus primary pneumothorax

 

Click here for medical student OSCE and PACES questions about Pneumothorax

Common Pneumothorax exam questions for medical students, finals, OSCEs and MRCP PACES

 

Click here to download free teaching notes on Pneumothorax: PneumothoraxBTS guidelines for pneumothorax

Perfect revision for medical students, finals, OSCEs and MRCP PACES