Deceleration accidents produce a complex of potentially fatal thoracic injuries. Because early detection is the key to successful management of blunt trauma to the great vessels, emergency physicians must be knowledgeable of signs indicative of these complex injuries. Among more than 10,000 patients presenting to the Ben Taub Emergency Center over an 11-year period with thoracic injuries, 100 had clinical or radiographic clues suggestive of blunt trauma decelerative injury to the great vessels. Of these 100 patients, 23 had transection of the descending thoracic aorta and five had avulsion of the innominate artery. One patient had a double transection. Six patients died in the Emergency Center before proximal control could be achieved.