Functional and survival outcomes in traumatic blunt thoracic aortic injuries: An analysis of the National Trauma Databank

Abstract

Blunt thoracic aortic injury (BAI) remains a leading cause of trauma deaths, and off-label use of endovascular devices has been increasingly utilized in an effort to reduce the morbidity and mortality in this population. Utilizing a nationwide database, we determined the incidence of BAI, and analyzed both functional and survival outcomes at discharge compared with matched controls. Patients with BAI were identified by International Classification of Disease-9 codes from the National Trauma Data Bank (Version 6.2), 2000-2005. Patients were analyzed based on aortic repair, associated physiologic burden, and coexisting injuries. Control groups were matched by age, mechanism, major thoracic Abbreviated Injury Scale score (AIS >/= 3), major head AIS, and major abdominal AIS. Outcomes were assessed using the functional independence measure (FIM) score and overall mortality. FIM scores were scored from 1 (full assistance required) to 4 (fully independent) for three categories: feeding, locomotion, and expression. During the study period, 3,114 patients with BAI were identified among 1.1 million trauma admissions for an overall incidence of 0.3%. One hundred thirteen (4%) were dead on arrival, and 599 (19%) died during triage. Of the patients surviving transport and triage (n = 2402), 29% had a concomitant major abdominal injury and 31% had a major head injury. Sixty-eight percent (1,642) underwent no repair, 28% (665) open aortic repair, and 4% (95) endovascular repair with associated mortality rates of 65%, 19%, and 18%, respectively (P < .05). Aortic repair independently improved survival when controlling for associated injuries and physiologic burden (odds ratio (OR) = 0.36; 95% confidence interval (CI), 0.24-0.54, P < .05). Compared with matched controls, BAI resulted in a higher mortality (55% vs. 15%, P < .05), and independently contributed to mortality (OR = 4.04; 95% CI, 3.53-4.63, P < .05). In addition, BAI patients were less likely to be fully independent for feeding (72% vs. 82%, P < .05), locomotion (33% vs. 55%, P < .05), and expression (80% vs 88%, P < .05). This manuscript is the first to define the incidence of BAI utilizing the NTDB. Remarkably, two-thirds of patients are unable to undergo attempts at aortic repair, which portends a poor prognosis. When controlling for associated injuries, blunt aortic injury independently impacts survival and results in poor function in those surviving to discharge.