Injuries to the azygous venous system.

BACKGROUND Azygous venous system injuries are rare. Although not commonly classified as a thoracic great vessel, the azygous system manifests morbidity and mortality that is similar to that of other great vessel injuries. METHODS Over a 40 year period, data were retrospectively collected and charts reviewed from a vascular injury database. RESULTS A total of 22 injuries to the azygous venous system were identified with 21 to the azygous vein and 1 to the hemiazygous vein. All were secondary to penetrating trauma, with 19 from gunshot wounds and 3 from stab wounds. Eight of 22 patients died for an overall mortality of 36%. All patients had associated injuries, with concomitant injury to the lung noted in all cases. CONCLUSIONS Injuries to the azygous venous system have a significant associated lethality. As an azygous venous injury is not typically the indication for operation, anterior incisions are often employed, making exposure difficult. In the majority of injured patients, the azygous system injury was found after excluding injuries to the heart, lung, and great vessels. A key finding in detecting these injuries through an anterior incision is continued hemorrhage of dark blood from a posterior location in the thoracic cavity. The azygous venous system should be considered early as a source of significant hemorrhage from the posterior mediastinum.