How do we manage a small pneumothorax (collapsed lung)?

Management of Small Pneumothorax

Small pneumothoraces without significant breathlessness should be managed with observation alone, with consideration for outpatient management if the pneumothorax is <2 cm and the patient has minimal symptoms. 1, 2

Definition and Diagnosis

• A small pneumothorax is defined as one with a visible rim of <2 cm between the lung margin and chest wall on a PA chest radiograph 1
• Diagnosis is typically established by plain chest radiography
  • Expiratory radiographs are not routinely indicated 1
  • Lateral or lateral decubitus radiographs can provide additional information when findings on PA radiographs are unclear 1
  • CT scanning is recommended only for difficult cases (e.g., overlying surgical emphysema) or to differentiate pneumothorax from bullae in complex cystic lung disease 1

Management Algorithm

1. Small Primary Pneumothorax (<2 cm) with Minimal/No Symptoms:

• Observation is the treatment of choice 1, 2
• Consider outpatient management if:
  • Patient lives within 30 minutes of hospital
  • Has adequate home support
  • Can return for follow-up within 12-48 hours 2
• Provide clear written instructions to return if breathlessness worsens 1

2. Small Pneumothorax with Symptoms:

• Important: Breathless patients should not be left without intervention regardless of the size of the pneumothorax on chest radiograph 1
• For symptomatic patients, options include:
  • Simple aspiration (first-line treatment) with success rates of 59-83% 2
  • If aspiration fails, proceed to tube drainage 2

3. Hospitalized Patients:

• Administer high-flow oxygen (10 L/min) to increase pneumothorax reabsorption rate four-fold
  • Use caution in COPD patients who may be sensitive to higher oxygen concentrations 1, 2
• Monitor for signs of clinical deterioration:
  • Increasing dyspnea
  • Tachycardia
  • Hypotension
  • Cyanosis 2

Special Considerations

Recurrence Prevention:

• Strong emphasis on smoking cessation (smoking significantly increases risk of pneumothorax) 2
• Consider intervention after first occurrence of secondary pneumothorax due to potential lethality 2
• For second pneumothorax:
  • Consider chemical pleurodesis through small-bore catheter for symptomatic patients preferring less invasive treatment
  • Consider elective surgery for second ipsilateral pneumothorax 2

Follow-up:

• Schedule follow-up within 12-48 hours for outpatient management 2
• Advise patients to avoid air travel for at least 7 days after confirmed resolution 2

Common Pitfalls and Caveats

• Don't underestimate small pneumothoraces: Even small pneumothoraces may have significant implications in patients with underlying lung disease 1
• Don't rely on pulmonary function tests: They are weakly sensitive measures of pneumothorax size/presence and are not recommended 1
• Don't miss tension pneumothorax: This is a medical emergency requiring immediate decompression, regardless of initial size 3
• Don't delay intervention for symptomatic patients: Breathless patients require intervention regardless of pneumothorax size 1
• Don't forget to provide clear discharge instructions: Patients need to understand when to return for worsening symptoms 1, 2

The management approach should be adjusted based on patient symptoms, pneumothorax size, and the presence of underlying lung disease, with observation being appropriate for small, asymptomatic primary pneumothoraces.