What is the management of tension pneumothorax?

Management of Tension Pneumothorax

Tension pneumothorax requires immediate needle decompression with a cannula of adequate length (at least 4.5 cm) inserted into the second intercostal space in the mid-clavicular line, followed by chest tube placement. 1

Clinical Recognition

Tension pneumothorax is a life-threatening emergency characterized by:

• Rapid labored respiration
• Cyanosis
• Sweating
• Tachycardia
• Hypotension
• Cardiorespiratory collapse
• Decreased or absent breath sounds on affected side

It should be particularly suspected in:

• Patients on mechanical ventilation who suddenly deteriorate
• Patients who develop EMD (electromechanical dissociation) arrest
• ICU settings where it is frequently missed 1

Immediate Management Algorithm

1. Administer high-concentration oxygen 1

2. Perform immediate needle decompression:

   • Insert a cannula into the second intercostal space in the mid-clavicular line
   • Use a cannula of at least 4.5 cm in length (as chest wall thickness exceeds 3 cm in 57% of patients) 1, 2
   • Insert perpendicular to chest wall all the way to the hub
   • Hold in place for 5-10 seconds to allow full decompression 3
   • Leave cannula in place until a functioning chest tube is positioned 1

3. Insert chest tube:

   • After needle decompression stabilizes the patient
   • Use tube size 16F-22F for most patients 4
   • Connect to water seal device with or without suction 4

4. Monitor for successful decompression:

   • Decreased respiratory distress
   • Improved oxygen saturation
   • Resolution of shock signs
   • Confirmation of proper tube function (bubbling in water seal system) 1, 3

Special Considerations

Mechanical Ventilation

Patients on mechanical ventilation are at higher risk for tension pneumothorax due to positive pressure maintaining air leaks 5. Even small undetected pneumothoraces can rapidly progress to tension pneumothorax when positive pressure ventilation is applied 6.

Chest Wall Thickness

Population-based studies recommend using a needle of at least 7 cm in length to successfully decompress tension pneumothorax in over 90% of patients 2. Standard recommendations for needle length (4.5 cm) may be insufficient in patients with thicker chest walls.

Alternative Decompression Sites

While the second intercostal space at the mid-clavicular line is the traditional site, the fifth intercostal space at the anterior axillary line is an acceptable alternative 3. The internal mammary artery is typically located sufficiently medial to the recommended puncture site, minimizing risk of iatrogenic injury 2.

Post-Decompression Management

1. Confirm tube position and function:

   • Check for respiratory swing in fluid level within chest tube
   • Absence of swing may indicate tube blockage or malposition 4

2. Provide adequate analgesia:

   • Local anesthetic infiltration
   • Consider opioids for additional pain control 4

3. Monitor for complications:

   • Pneumonia (higher risk in patients with prolonged air leaks)
   • Prolonged hospitalization
   • Need for surgical intervention 4

4. Chest tube removal:

   • Remove when clinical resolution is achieved
   • Confirm lung re-expansion on chest radiograph
   • Ensure air leak has resolved
   • Remove during expiration or Valsalva maneuver 4

Pitfalls and Caveats

1. Delayed recognition: The clinical scenario of tension pneumothorax may correlate poorly with radiographic findings. Do not wait for radiographic confirmation if clinical signs are present 1.

2. Inadequate needle length: Using too short a needle is a common cause of decompression failure 2.

3. Failure to recognize in ventilated patients: Tension pneumothorax should be suspected in any ventilated patient with sudden deterioration 6, 5.

4. Insufficient monitoring after decompression: Continue to monitor closely as re-accumulation can occur, particularly in patients on positive pressure ventilation 5.