What is the best course of treatment for a patient presenting with a large pneumothorax?

Management of Large Pneumothorax

Clinically stable patients with large pneumothorax (≥3 cm apex-to-cupola distance) should undergo chest tube placement and hospitalization. 1

Initial Assessment and Stabilization

Clinical stability must be determined first using these criteria: respiratory rate <24 breaths/min, heart rate 60-120 beats/min, normal blood pressure, room air oxygen saturation >90%, and ability to speak in complete sentences between breaths. 1

• Unstable patients require immediate chest tube placement regardless of pneumothorax size, with no delay for imaging beyond what is immediately available. 1
• Never refer patients directly to thoracoscopy without prior chest tube stabilization, even if definitive surgical management is anticipated. 1

Chest Tube Selection Algorithm

For Clinically Stable Patients:

• Use 16F to 22F chest tubes as first-line therapy (good consensus). 1
• Small-bore catheters (≤14F) are acceptable alternatives in select circumstances including patient preference or very small pneumothoraces, though panel members expressed concern about occlusion risk. 1

For Clinically Unstable Patients or High-Risk Situations:

• Use 24F to 28F chest tubes for patients who are unstable or require mechanical ventilation due to risk of large pleural air leaks. 1, 2
• Larger tubes (30-36F) are not necessary and offer no additional benefit. 1

Drainage System Management

Connect the chest tube to a water seal device initially without suction for most stable patients (good consensus). 1, 2

• Apply suction (-10 to -20 cm H₂O) if:

  • The lung fails to reexpand on water seal alone after initial placement 1, 2
  • The patient requires positive-pressure ventilation 2
  • Large persistent air leak is present 2

• Heimlich valves are acceptable alternatives but water seal devices are preferred for most hospitalized patients. 1, 3

Critical Safety Considerations

Never clamp a bubbling chest tube, as this can convert a simple pneumothorax into life-threatening tension pneumothorax, particularly in ventilated patients where positive pressure continuously forces air into the pleural space. 2, 3

• In mechanically ventilated patients, even small undetected pneumothoraces can rapidly progress to tension pneumothorax through positive pressure ventilation. 4
• For spontaneously breathing patients with suspected tension physiology, if hemodynamically stable, carefully monitor and obtain portable chest radiography before intervention rather than performing blind needle decompression. 5

Timeline for Escalation

• Refer to respiratory specialist at 48 hours if pneumothorax fails to respond or persistent air leak continues. 2
• Consider surgical intervention at 5-7 days for persistent air leak in patients without pre-existing lung disease. 2
• Earlier surgical referral (2-4 days) is appropriate for patients with underlying lung disease (secondary pneumothorax), large persistent air leak, or failure of lung to re-expand. 2

Recurrence Prevention

Most experts (81%) recommend intervention to prevent recurrence after the first episode of secondary pneumothorax due to potential lethality, while 19% would wait until the second episode. 1

• Surgical intervention is strongly preferred over chemical pleurodesis through chest tube due to lower recurrence rates. 1
• Medical or surgical thoracoscopy is the preferred approach with staple bullectomy and pleural symphysis (via parietal pleurectomy, talc poudrage, or pleural abrasion). 1

Common Pitfalls to Avoid

• Do not use small-bore catheters (≤14F) in ventilated patients, as they are inadequate for the air leak volume generated by positive-pressure ventilation. 2
• Avoid high-pressure suction systems (>-20 cm H₂O), as they can cause re-expansion pulmonary edema, air stealing, hypoxemia, or perpetuate persistent air leaks. 2
• Do not discharge patients without careful instructions for follow-up within 12 hours to 2 days and warning signs requiring immediate return. 1