Pleural controversy: optimal chest tube size for drainage.

In recent years, a higher and higher percentage of patients with pleural effusions or pneumothorax are being treated with small-bore (10-14 F) chest tubes rather than large-bore (>20 F). However, there are very few randomized controlled studies comparing the efficacy and complication rates with the small- and large-bore catheters. Moreover, the randomized trials that are available have flaws in their design. The advantages of the small-bore catheters are that they are easier to insert and there is less pain with their insertion while they are in place. The placement of the small-bore catheters is probably more optimal when placement is done with ultrasound guidance. Small-bore chest tubes are recommended when pleurodesis is performed. The success of the small-bore indwelling tunnelled catheters that are left in place for weeks documents that the small-bore tubes do not commonly become obstructed with fibrin. Patients with complicated parapneumonic effusions are probably best managed with small-bore catheters even when the pleural fluid is purulent. Patients with haemothorax are best managed with large-bore catheters because of blood clots and the high volume of pleural fluid. Most patients with pneumothorax can be managed with aspiration or small-bore chest tubes. If these fail, a large-bore chest tube may be necessary. Patients on mechanical ventilation with barotrauma induced pneumothoraces are best managed with large-bore chest tubes.