The impact of polytrauma on sRAGE levels: evidence and statistical analysis of temporal variations

BACKGROUND: According to recently published findings, levels of the soluble receptor of advanced glycation end products (sRAGE) and its clearance from the blood may reflect the evolution of lung damage during hospitalization. Thus, the objective of this study was to reveal the course of sRAGE levels over the first three posttraumatic weeks, focusing on the severity of thoracic trauma and the development of acute respiratory distress syndrome (ARDS) and/or pneumonia. METHODS: Twenty-eight consecutive surviving polytraumatized patients suffering thoracic trauma, age ≥ 18 years, Injury Severity Score ≥ 16, and directly admitted to our level I trauma center were enrolled in this prospective study. Blood samples were taken initially and on days 1, 3, 5, 7, 10, 14, and 21 during hospitalization. Luminex multi-analyte-technology was used for biomarker analysis. RESULTS: Common to all our patients was an almost continuous decline of sRAGE levels within the first five posttraumatic days. Day 0 levels in polytrauma victims with severe thoracic trauma were more than twice as high than in those suffering mild thoracic trauma (p = 0.035), whereas the difference between the two groups did not reach significance from day 1. Neither the development of ARDS and/or pneumonia nor the necessity of secondary surgery did result in significant differences in sRAGE levels between the subgroups with and without the particular complication at any time point. CONCLUSIONS: sRAGE levels assessed immediately after hospital admission might serve as a diagnostic marker for the vehemence of impacts against the chest and thus might be applied as an additional tool in diagnosis, risk evaluation, and choice of the appropriate treatment strategy of polytraumatized patients in routine clinical practice.