How long should negative suction be applied for a non-expanding pneumothorax?

Duration of Negative Suction for Non-Expanding Pneumothorax

Negative suction should only be applied after 48 hours of standard chest tube drainage if the pneumothorax is slow to re-expand, and should then be continued for up to 5-7 days before considering surgical referral. 1

Initial Management Approach

1. Begin with standard chest tube drainage without suction

   • Allow 48 hours for spontaneous resolution with standard drainage
   • This minimizes the risk of re-expansion pulmonary edema, especially in primary pneumothoraces that have been present for several days 1

2. Monitor for lung re-expansion during this initial period

   • Confirm with chest radiographs
   • Assess for clinical improvement

When to Apply Suction

Apply negative suction only if:

• The pneumothorax is slow to re-expand after 48 hours
• Standard drainage has failed to achieve lung re-expansion 1

Suction Parameters

When suction is indicated:

• Use negative pressure of -10 to -20 cm H₂O
• Apply using a high volume, low pressure system (e.g., Vernon-Thompson pump or wall suction with pressure-reducing adaptor)
• Avoid high pressure systems which can cause:
  • Air stealing
  • Hypoxemia
  • Perpetuation of persistent air leaks 1

Duration of Suction

• Continue suction for up to 5-7 days
• If air leak persists after this period, refer for surgical evaluation 1

Criteria for Chest Tube Removal

Remove chest tube when:

• No air leak is present
• Drainage is <100-150 mL per 24 hours (for fluid)
• Lung expansion is confirmed on chest radiograph 1

Complications to Monitor

Be vigilant for complications of suction, particularly:

• Re-expansion pulmonary edema (REPE)
  • More common in patients younger than 40 years
  • More frequent with large pneumothoraces
  • Higher risk when lung collapse has been present for more than one week
  • Can occur with immediate application of suction 2
• Subcutaneous emphysema
• Persistent air leak
• Hemodynamic instability 1

Special Considerations

1. For patients with risk factors for REPE:

   • Avoid immediate suction after chest tube placement
   • Reserve suction for cases of treatment failure after 24 hours 2

2. For persistent air leaks:

   • Consider earlier surgical referral (2-4 days) if:
     • Large persistent air leak continues
     • Lung fails to re-expand
     • Underlying lung disease is present 1

3. Patients on suction should be:

   • Placed in an area with specialized nursing experience
   • Monitored closely for complications 1

Follow-up Care

• Confirm lung re-expansion with post-procedure chest X-ray
• Arrange follow-up within 7-10 days after discharge
• Advise patients to avoid air travel until chest radiograph confirms complete resolution 1