What are the causes of non-expansion of the lung after insertion of an intercostal (IC) tube?

Causes of Non-Expansion of Lung After Intercostal Tube Insertion

The most common causes of persistent lung non-expansion after chest tube insertion are persistent air leak, tube malposition or blockage, trapped lung/lung entrapment from visceral pleural disease, and underlying parenchymal disease preventing re-expansion. 1, 2, 3

Primary Mechanical Causes

Tube-Related Problems

• Malpositioned, kinked, or blocked chest tubes are frequent preventable causes that should be assessed immediately when the lung fails to expand 2, 4, 5
• Verify tube position with chest radiography after insertion to rule out malposition and confirm proper placement 4
• Check tube patency by flushing with 20-50ml normal saline if drainage is poor 4
• Consider placing a second chest tube rather than relying on repositioning if a residual collection persists despite a patent first tube 4

Persistent Air Leak

• A persistent air leak is arbitrarily defined as continued air bubbling through the tube 48 hours after insertion 1
• The median time to resolution of spontaneous pneumothorax is 8 days (19 days in those with underlying lung disease), which is not related to initial pneumothorax size 1
• Apply suction (high volume, low pressure systems at -10 to -20 cm H₂O) after 48 hours if the lung remains unexpanded 1
• Refer for surgical opinion at 5-7 days for persistent air leak without pre-existing lung disease, or earlier (2-4 days) in those with underlying disease, large persistent air leak, or failure of lung re-expansion 1

Pleural Disease Causing Unexpandable Lung

Trapped Lung vs. Lung Entrapment

• Unexpandable lung occurs in at least 30% of patients with malignant pleural effusions and represents the inability of the lung to expand to the chest wall despite drainage 1, 3
• Trapped lung is caused by formation of a fibrous visceral pleural peel in the absence of active inflammation or malignancy; the mechanical peel itself is the primary problem 3
• Lung entrapment results from active pleural inflammation, infection, or malignancy creating a visceral pleural peel; the underlying disease is the primary problem 3
• Pleural manometry during drainage can identify unexpandable lung and predict post-thoracentesis pneumothorax 3
• The absence of lung expansion after fluid evacuation should steer clinicians away from futile pleurodesis attempts and toward indwelling pleural catheters 1

Multiloculated Collections

• For multiloculated pleural collections resistant to simple drainage, consider intrapleural fibrinolytic therapy (streptokinase 250,000 IU twice daily for 3 days or urokinase 100,000 IU once daily for 3 days) rather than continued drainage alone 2, 4
• Clamp the tube for 1 hour after fibrinolytic administration 2

Underlying Parenchymal Disease

Endobronchial Obstruction and Atelectasis

• Endobronchial obstruction resulting in lobar collapse or chronic atelectasis directly prevents lung expansion 3
• Extensive ipsilateral consolidation can create a small, non-recruitable lung that cannot expand despite tube drainage 6

Congenital Malformations

• Congenital lobar emphysema is a rare cystic malformation often confused with pneumothorax; non-improvement of distress and non-expansion after tube insertion should prompt CT imaging for diagnosis 7

Iatrogenic Complications Preventing Expansion

Re-Expansion Pulmonary Edema

• Adding suction too early after chest tube insertion, particularly for primary pneumothorax present for several days, may precipitate re-expansion pulmonary edema 1
• This complication can range from asymptomatic to rapidly fatal and may occur within hours of drainage in massive, long-standing pneumothorax 8
• Risk factors include chronic lung collapse, rapid re-expansion, and changes in pulmonary vascular permeability 8

Subcutaneous Emphysema

• Develops when air communicates with subcutaneous tissues through a malpositioned, kinked, blocked, or clamped tube 4, 5
• If a patient develops worsening subcutaneous emphysema, immediately check for tube clamping, kinking, or displacement 5
• Never clamp a bubbling chest tube as this prevents air egress and forces air into surrounding tissues 4, 5

Diagnostic Algorithm When Lung Fails to Expand

1. Immediately assess tube function: Check for kinking, blockage, or malposition on chest radiograph 2, 4
2. Verify air leak status: Observe for bubbling in the underwater seal 1, 2
3. If persistent air leak >48 hours: Apply high-volume, low-pressure suction at -10 to -20 cm H₂O 1
4. If no air leak but poor drainage: Flush tube with 20-50ml saline to confirm patency 4
5. If tube patent but lung unexpanded: Obtain contrast-enhanced CT to assess for trapped lung, loculations, or underlying parenchymal disease 4, 3
6. Consider pleural manometry during drainage to identify unexpandable lung 3
7. Refer to thoracic surgery at 3-5 days for persistent air leak or failure of lung re-expansion 1, 2

Critical Pitfalls to Avoid

• Never use a trocar or substantial force during insertion, as this causes organ injury and potential pulmonary artery damage 4, 9
• Never clamp a bubbling chest tube, as this can convert simple pneumothorax into life-threatening tension pneumothorax 2, 4, 5
• Do not attempt pleurodesis in patients with unexpandable lung, as it is futile; use indwelling pleural catheters instead 1
• Avoid applying suction too rapidly in long-standing pneumothorax due to re-expansion pulmonary edema risk 1, 8
• Patients requiring complex drain management should be referred to a respiratory physician 2