Indications for Chest Tube Placement
Chest tubes should be placed for pneumothorax, hemothorax, pleural empyema, complicated parapneumonic effusions with specific biochemical criteria (pleural pH <7.2), and large symptomatic pleural effusions. 1, 2, 3
Primary Indications
Pleural Infection and Parapneumonic Effusions
The most critical indication is pleural infection, where pleural fluid pH <7.2 predicts the need for drainage and should trigger immediate chest tube placement. 1 This pH threshold is superior to other biochemical markers including LDH and glucose levels for determining drainage necessity. 1
- Frank pus (empyema) always requires chest tube drainage without need for pH measurement. 1
- Pleural fluid pH should be measured anaerobically with heparin using a blood gas analyzer, not litmus paper or pH meters. 1
- Loculated pleural collections require earlier chest tube drainage due to association with poorer outcomes. 1
- Large pleural collections (>40% of hemithorax) are more likely to require surgical intervention and warrant chest tube placement. 1
Important caveat: Parapneumonic effusions with pH >7.2 may initially be observed with antibiotics alone, but unsatisfactory clinical progress mandates repeated sampling and possible drainage. 1 pH is specific but not 100% sensitive for predicting drainage needs. 1
Pneumothorax
Large pneumothoraces always require chest tube placement regardless of clinical stability. 1 The severity of underlying pulmonary impairment does not change this recommendation. 1
- Small pneumothoraces require chest tube placement only if the patient is clinically unstable. 1
- Clinically stable patients with small pneumothoraces may be observed closely in the outpatient setting. 1
- In primary spontaneous pneumothorax with minimal symptoms, needle aspiration and discharge may be considered. 1
Hemothorax
Traumatic hemothorax requires chest tube drainage to evacuate blood and allow lung re-expansion. 2, 3, 4 Tube size selection (28Fr vs smaller) does not significantly affect outcomes for residual hemothorax or tube occlusion. 4
Large Symptomatic Effusions
Non-purulent effusions without acidosis should be drained by chest tube for symptomatic benefit when they are large and causing respiratory compromise. 1
Pediatric-Specific Indications
In children with community-acquired pneumonia and parapneumonic effusions:
- Small, uncomplicated parapneumonic effusions should NOT be routinely drained and can be treated with antibiotics alone. 1
- Moderate effusions with respiratory distress, large effusions, or documented purulent effusions require drainage. 1
- Loculated effusions cannot be drained with chest tube alone and require adjunctive therapy (fibrinolysis or VATS). 1
Additional Considerations
Specialist Involvement
A respiratory physician or thoracic surgeon should be involved in all cases requiring chest tube drainage for pleural infection. 1 Delay in chest tube drainage is associated with increased morbidity, prolonged hospital stay, and potentially increased mortality. 1
Prophylactic Drainage
Chest tubes are indicated prophylactically after major thoracic surgery to drain air, blood, and other fluids. 2, 3, 5
Common Pitfalls to Avoid
- Never use trocars for chest tube insertion due to high risk of intrathoracic organ damage, hemothorax, and lung lacerations. 1, 2, 3
- Do not rely on radiographic appearance alone to reposition a functioning drain. 1
- Be aware that lignocaine is acidic and can artificially depress pleural fluid pH if contamination occurs. 1
- Delay in drainage significantly worsens outcomes—misdiagnosis, inappropriate antibiotics, and inappropriate tube placement contribute to progression of pleural infection. 1