BackgroundEndothelial glycocalyx (EG) abnormal degradation were widely found in critical illness. However, data of EG degradation in multiple traumas is limited. We performed a study to assess the EG degradation and the correlation between the degradation and organ functions in multiple trauma patients. MethodsA prospective observational study was conducted to enroll health participants (control group) and multiple traumas patients (trauma group) at a University affiliated hospital between Feb 2020 and Oct 2020. Syndecan1 (SDC1) and heparin sulfate (HS) were detected in serum sample of both groups. In trauma group, injury severity scores (ISS) and sequential organ failure assessments (SOFA) were calculated. Occurrences of acute kidney injury (AKI), trauma-induced coagulopathy (TIC) within 48 hours and 28-day all-cause mortality in trauma group were recorded. Serum SDC1 and HS levels were compared between two groups. Correlations between SDC1/HS and the indicators of organ systems in the trauma group were analyzed. ROC analyses were performed to assess the predictive value of SDC1 and HS for AKI, TIC within 48 hours, and 28-day mortality in trauma group. ResultsThere were 45 multiple trauma patients and 15 healthy participants were collected, totally. SDC1 and HS were significantly higher in trauma group than in control group (69.39 [54.18–130.80] vs. 24.15 [13.89–32.36], 38.92 [30.47–67.96] vs. 15.55 [11.89–23.24], P<0.001, respectively). SDC1 and HS were both positively correlated with prothrombin time, activated partial thromboplastin time, EVLW, N-terminal pro-B-type natriuretic peptide, myoglobin, creatinine, lactic acid, interleukin-6, and tumor necrosis factor-α (P<0.05, respectively). SDC1 and HS were both negatively correlated with Ca2+, anti-thrombin-III, PaO2/FiO2 ratio, pH and albumin (P<0.05, respectively). Trauma group was divided into high degradation group and low degradation group according to SDC1 median. High degradation group had more severe ISS, SOFA scores, worse organ functions (respiratory, kidney, coagulation and metabolic system), and higher incidence of hypothermia, acidosis and shock. ROC curve analyses demonstrated SDC1 can predict the occurrence risk of AKI, TIC within 48h, and 28-day mortality. ConclusionsEG degradation was elevated significantly in multiple trauma patients, and the degradation was correlated with impaired respiratory, kidney, coagulation and metabolic systems. Serum SDC1 is a valuable predictive indicator of early TIC, AKI risk, and 28-day mortality in multiple trauma patients.