How important is it to connect a chest tube to a water seal in a trauma situation?

Importance of Connecting Chest Tubes to Water Seal in Trauma Situations

In a trauma situation, it is absolutely critical to immediately connect a chest tube to a unidirectional flow drainage system (such as an underwater seal) as this prevents potentially fatal complications including tension pneumothorax, infection, and surgical emphysema. 1

Rationale for Immediate Connection

• Chest tubes should never be left open to air in trauma cases, even briefly, as this creates significant risks:

  • Development of tension pneumothorax (life-threatening)
  • Increased risk of pleural infection (up to 6% in trauma cases)
  • Development of subcutaneous emphysema leading to respiratory compromise 1

• The drainage system must allow unidirectional flow of air or fluid out of the chest, preventing atmospheric air from entering the pleural space 2

Proper Drainage System Management

Types of Drainage Systems

• Traditional underwater seal system:

  • Tube placed under water at depth of 1-2 cm
  • Side vent allows escape of air or connection to suction
  • More cumbersome but effective for managing large air leaks 2
  • Must be kept below the level of the patient's chest at all times 2

• One-way flutter valve systems:

  • Portable alternative to underwater seal
  • Allow for earlier patient mobility
  • Equally effective for most cases 3

Critical Safety Points

• A bubbling chest tube should NEVER be clamped, as this can convert a simple pneumothorax into a life-threatening tension pneumothorax 2

• Chest tubes that are not bubbling should generally not be clamped either 2

• If a clamped drain is necessary (e.g., after intrapleural fibrinolytic administration), this should only be done:

  • Under supervision of a respiratory physician or thoracic surgeon
  • With the patient in a specialized ward with experienced nursing staff
  • With standing instructions to immediately unclamp if the patient develops breathlessness or chest pain 2

Suction Considerations

• If suction is used, it should be applied at low pressure (5-10 cm H2O) to prevent blockage of the drain with debris 2

• For trauma patients, mild suction of approximately 20 cmH2O is recommended 4

• Brief disconnection from suction for activities like radiographs is acceptable, provided:

  • Clear instructions are given to keep the underwater seal bottle below chest level
  • The patient is monitored appropriately 2

Chest Tube Size Selection in Trauma

• For unstable trauma patients: Large-bore tubes (≥24 French) are recommended 4
• For stable trauma patients: Small-bore tubes (e.g., 14 French) may be sufficient 4, 5

Complications and Prevention

• Chest tube insertion has a complication rate of 5-25%, with incorrect positioning being most common 4, 6

• Leaving a chest tube open to air or improperly connected significantly increases these risks 1

• Proper training of medical staff is essential to reduce complications 4, 6

Monitoring After Connection

• A normal chest radiograph obtained 3 hours after placing a chest tube on water seal effectively excludes development of a clinically significant pneumothorax 7

• Respiratory swing in the fluid level of the chest tube confirms tube patency and proper positioning in the pleural cavity 2

In summary, immediate connection of chest tubes to a water seal or one-way valve system in trauma situations is not optional—it is an essential safety measure that prevents life-threatening complications and should never be omitted or delayed.