How important is it to connect chest tubes to a Heimlich valve (one-way valve) or other drainage system during trauma, and is it okay to leave them open to air for a short period?

Chest Tube Connection to Heimlich Valve or Drainage System in Trauma

Chest tubes should never be left open to air in trauma cases as this risks tension pneumothorax, infection, and surgical emphysema; immediate connection to a one-way valve system (Heimlich) or underwater seal is essential for patient safety. 1, 2

Immediate Management of Chest Tubes in Trauma

• A chest tube that is bubbling (indicating active air leak) must NEVER be left open to air or clamped, as this can convert a simple pneumothorax into a life-threatening tension pneumothorax 1
• Even brief exposure to air without a one-way valve system can lead to:
  • Potential tension pneumothorax development
  • Increased risk of pleural infection (reported up to 6% in trauma cases) 1
  • Development of subcutaneous emphysema, which can lead to respiratory compromise 2

Drainage System Options

1. Heimlich Valve (One-way Valve):

   • Allows air and fluid to exit the pleural space but prevents return
   • Functions in any position and never needs to be clamped 3
   • Facilitates patient mobility as it drains into a portable collection bag 3
   • Particularly useful in emergency settings including trauma 4

2. Traditional Underwater Seal System:

   • More cumbersome but effective for managing large air leaks
   • Must be kept upright, limiting patient mobility 1
   • May be preferred for patients with large volume drainage or on mechanical ventilation 5

Critical Considerations in Trauma

• Tube Size Selection:

  • Small-bore tubes (10-14F) are generally adequate for most pneumothoraces 1, 2
  • Larger tubes (16-22F) may be needed for large air leaks or mechanical ventilation 2
  • Larger tubes (24-28F) for massive air leaks or hemothorax 2, 5

• Connection Timing:

  • Connection to a drainage system must be immediate - there is no safe period for a chest tube to remain open to air in trauma 1, 2
  • Any delay increases risk of tension pneumothorax, especially with active air leak 1

Complications of Improper Management

• Leaving tube open to air risks:

  • Tension pneumothorax (potentially fatal) 1
  • Pleural infection (1-6% incidence in trauma) 1
  • Subcutaneous emphysema that may lead to respiratory compromise 1, 2
  • Air stealing and hypoxemia 2

• Signs of complications requiring immediate intervention:

  • Patient becoming breathless
  • Development of subcutaneous emphysema
  • Decreased oxygen saturation
  • Hemodynamic instability 1, 2

Management Algorithm

1. Insert chest tube using proper technique and aseptic precautions
2. Immediately connect to either:
   • Heimlich valve (preferred in field/emergency settings) 4, 3
   • Underwater seal drainage system (for hospital setting/large drainage)
3. Never leave tube open to air, even briefly
4. Monitor for bubbling (air leak) and drainage
5. Apply suction only if lung fails to re-expand after 48 hours 2
6. Refer to respiratory specialist if pneumothorax fails to resolve within 48 hours 1

Common Pitfalls to Avoid

• Never clamp a bubbling chest tube - this can convert a simple pneumothorax to tension pneumothorax 1
• Never leave a chest tube open to air - even briefly 1, 2
• Avoid breaking sterile field to access inside of chest tubes as this increases infection risk 2
• Don't delay connection to appropriate drainage system after insertion 1, 2

The evidence is clear that chest tubes must be connected to an appropriate drainage system immediately upon insertion, with no safe period for leaving them open to air in trauma cases.