Abstract
OBJECTIVES: Shedding of the proteoglycan syndecan-1 (SDC-1) from the vascular endothelial surface into the circulation in severe trauma predicts mortality in trauma patients. However, the timing and duration of SDC-1 elevation in trauma patients have not been defined. The primary aim of this study was to describe the longitudinal pattern of SDC-1 elevation in trauma patients with either mechanical and/or burn injury during the first 120 hours of resuscitation and initial stabilization. Our secondary objective was to determine the association of endotheliopathy, as defined by elevated SDC-1 levels, with trauma-induced coagulopathy (international normalized ratio [INR] ≥ 1.4). METHODS: This prospective observational study enrolled adults meeting trauma activation criteria at 1 of 3 trauma centers. The blood was collected at presentation in the emergency department (time 0) and again at 2, 4, 6, 12, 24, 72, 96, and 120 hours. SDC-1 was quantified by ELISA, and elevated levels were defined as ≥40 ng/mL. The primary outcome of coagulopathy was defined as a clinical laboratory report of INR ≥ 1.4 during this timeframe. We determined the association between elevated SDC-1 and coagulopathy using logistic regression and adjusted for age, sex, burn status, and injury severity. RESULTS: We studied 301 severely injured individuals, including those with mechanical and burn injuries. Among these individuals, 96 (31.9%) had coagulopathy, 122 (40.5%) required transfusions, and 42 (14%) died. SDC-1 plasma levels were significantly greater in subjects with coagulopathy relative to noncoagulopathic patients. Plasma levels of SDC-1 ≥ 40 ng/mL conferred significantly increased odds of presenting with INR ≥ 1.4, with an adjusted odds ratio of 17.88 (95% CI, 5.14-62.24), P < .05. High SDC-1 levels (≥40 ng/mL) were most often evident at the initial blood draw and tended to remain elevated. CONCLUSION: Plasma SDC-1 peaks early and remains elevated across time in most individuals with mechanical and/or burn injury. Individuals with elevated SDC-1 levels have an increased risk of coagulopathy independent of injury severity.