Impact of presenting physiology and associated injuries on outcome following traumatic rupture of the thoracic aorta

We hypothesized that the predominant factor influencing outcome of traumati c rupture of the thoracic aorta (TRA) was the degree of shock on presentati on and associated injuries. We reviewed our experience with TRA over a 15-y ear period. Patients were classified as "unstable" if presenting systolic b lood pressure was <90 mm Hg or if it decreased to <90 mm Hg after admission . We determined the presence of closed head injury, cardiac risk factors, a preoperative acute lung injury (ALI). The influence of these factors on mo rtality, postoperative adult respiratory distress syndrome (ARDS), and para lysis was analyzed. One hundred thirty-six patients were admitted with TRA. One hundred twenty underwent operative repair with a mortality of 31 per c ent. Operative mortality was significantly higher in unstable patients (62% ) versus stable patients (17%, P = 0.001), in patients with cardiac risk fa ctors (71%) versus those without (24%, P = 0.001), and in patients with pre operative free rupture (83%) with versus those without (19%, P = 0.001). Fr ee rupture was the cause of hypotension in only 10 of 42 unstable patients, with the remainder being due to other causes. Preoperative ALI was associa ted with a marked increase in postoperative ARDS (47% with vs 9% without, P = 0.001) but not operative mortality. Mechanical circulatory support (MCS) was used in 59 cases, none of whom experienced paralysis, whereas eight of 61 operated on without MCS developed paralysis (P = 0.001). When logistic regression was applied the use of MCS was not determined to be statisticall y significant. However, preoperative instability was found to be a signific ant predictor of postoperative paralysis with the risk being increased 5.5 times (confidence interval 3.3-10). The predominant factor influencing mort ality, postoperative ARDS, and paralysis was preoperative instability and a ssociated injuries. In patients who are hypotensive, other injuries should take precedence over repair of TRA. Patients who are stable but who have ca rdiac or pulmonary risk factors may be better managed by a period of nonope rative management until their condition improves.