Traditional teaching is that chest tubes placed to evacuate a pneumothorax should be directed anterior and superior and to evacuate fluid should be directed posterior and inferior.
A recent study examined the effect of specific chest tube position on chest tube function. This was a retrospective review of 291 patients with chest tubes placed in the ER. These patients underwent a tomography scan following the insertion of the chest tube to accurately determine the position of the chest tube.
Results showed that as long as the chest tube was in the pleural space, secondary interventions were not necessary. The study identified the following risk factors that increased the need for a secondary intervention: a high chest Abbreviated Injury Scale (AIS) score of 3 or more, mechanism of injury, and volume of the hemothorax. With regards to mechanism of injury, there is a higher chance that the patient will need a thoracotomy for penetrating chest trauma as opposed to blunt chest trauma. For a hemothorax, there is a higher need to for surgery if the initial hemothorax is large enough to cause lung volume loss vs smaller hemothoraces.
The most important outcome for tube thoracostomy is the safe insertion of a chest tube within the pleural space. The chest tube should be able to drain air or fluid effectively regardless of the specific tube location within the pleural space.
Another study sought to determine the efficacy of small and large chest tubes for thoracic trauma. A total of 535 chest tubes were placed in 293 patients. Of these chest tubes, 186 were small (<=20 French) and 167 were large (>20 French). The size of the chest tube had no effect on drainage, rate of complications, need for additional tube drainage, or invasive procedures. Overall, there was no significant difference between using a small or large chest tube in the setting of chest trauma.
Inaba K, et al. Does size matter? A prospective analysis of 28-32 versus 36-40 French chest tube size in trauma. J Trauma Acute Care Surg. 2012 Feb; 72(2):422-7
Benns MV, et al. Does chest tube location matter? An analysis of chest tube position and the need for secondary interventions. J Trauma Acute Care Surg. 2015 Feb; 78(2):386-90