Should a chest tube be placed to suction in a patient requiring BiPAP (Bilevel Positive Airway Pressure) or CPAP (Continuous Positive Airway Pressure)?

Management of Chest Tubes in Patients Requiring BiPAP or CPAP

For patients with a chest tube who require BiPAP or CPAP therapy, the chest tube should initially be placed to water seal without suction, and only switched to suction if there is evidence of a large pneumothorax or significant air leak.

Rationale for Initial Water Seal Approach

• The European Respiratory Society and European Society of Intensive Care Medicine task force on physiotherapy for critically ill patients recommends maintaining airway pressures within safe limits when providing ventilatory support 1.

• When managing chest tubes in patients with pneumothorax, the initial approach should be connection to a water seal drainage system without suction, as recommended by the American College of Chest Physicians 2.

• Water seal management (without suction) has been shown to be superior for most patients with air leaks, resulting in:

  • Shorter duration of chest tube placement
  • Shorter hospital length of stay 3, 4

When to Consider Adding Suction

Suction should be added to the chest tube system if:

1. The pneumothorax is large (>8 cm) 3
2. There is a large air leak (particularly during expiration) 3
3. The lung fails to re-expand with water seal alone 2
4. The patient develops subcutaneous emphysema 2
5. There is evidence of an expanding symptomatic pneumothorax 3

Physiological Considerations with BiPAP/CPAP

• BiPAP and CPAP deliver positive pressure to the airways, which can:

  • Potentially worsen air leaks through the pleural space
  • Increase the risk of tension pneumothorax if the chest tube is inadequate 1
  • Cause barotrauma if excessive pressure is applied 1

• Non-invasive positive pressure ventilation (CPAP, BiPAP) should be used with caution in patients with chest tubes, as it can affect blood pressure and respiratory mechanics 1.

Monitoring Protocol

1. Obtain a chest radiograph after chest tube placement to confirm position and assess initial lung re-expansion 2.

2. Monitor for:

   • Persistent air leak (bubbling in the water seal chamber)
   • Size of pneumothorax on imaging
   • Signs of respiratory distress
   • Subcutaneous emphysema
   • Hemodynamic stability

3. If the pneumothorax persists or worsens with BiPAP/CPAP while on water seal, apply appropriate suction to the chest tube 2.

Important Precautions

• Never clamp a bubbling chest tube as this can convert a simple pneumothorax into a life-threatening tension pneumothorax 2.

• Excessive suction should be avoided as it may:

  • Prolong air leaks due to alveolar over-distension 5
  • Potentially cause negative pressure pulmonary edema in certain patients 6

• For patients requiring BiPAP/CPAP, ensure careful monitoring of both the chest tube system and ventilatory parameters to prevent complications.

Chest Tube Removal Criteria

Before removing the chest tube in a patient on BiPAP/CPAP:

1. Confirm complete resolution of pneumothorax by chest radiograph
2. Verify no clinical evidence of ongoing air leak
3. If the patient remains on BiPAP/CPAP, consider temporarily discontinuing positive pressure during tube removal if clinically feasible

Special Considerations

• In patients with both pneumothorax and air leak, those with large air leaks or large pneumothoraces are more likely to fail water seal management and require suction 3.

• Patients on mechanical ventilation (including BiPAP/CPAP) with chest tubes require careful monitoring for tension pneumothorax, which is a life-threatening emergency 2.