[Prognostic value of the dynamic changes in extra vascular lung water index and angiopoietin-2 in severe multiple trauma patients with acute respiratory distress syndrome].

Objective: To observe the dynamic changes in extra vascular lung water index (EVLWI) and angiopoietin-2 (Ang-2) in severe multiple trauma patients with acute respiratory distress syndrome (ARDS), analyze the risk factor for short-term mortality, and to evaluate their prognostic values for prognosis.

Methods: A total of 54 severe multiple trauma patients with ARDS admitted to emergency intensive care unit (ICU) of the Affiliated Hospital of Guizhou Medical University from June 2014 to December 2018 were enrolled. The acute physiology and chronic health evaluation II (APACHE II), injury severity score (ISS) and oxygenation index (PaO/FiO), EVLWI [pulse-induced contour cardiac output (PiCCO) monitor] and plasma Ang-2 level [enzyme-linked immunosorbent assay (ELISA)] at 0 (immediately), 24, 48 and 72 hours after ICU admission, and the differences in PaO/FiO, EVLWI and Ang-2 between 0 hour and 72 hours (ΔPaO/FiO, ΔEVLWI, ΔAng-2) were calculated. The 28-day survival of patients was recorded, and the patients were divided into survival group and non-survival group. The differences in above mentioned parameters between the two groups were compared. Multivariate Logistic regression was used to analyze the independent risk factors associated with the prognosis. Receiver operating characteristic (ROC) curve was drawn to evaluate the prognostic values of ΔEVLWI and ΔAng-2 on the prognosis, and the Kaplan-Meier survival curve was plotted.

Results: 115 patients were enrolled in the final analysis, 72 survived in 28 days, 43 died, and the mortality rate was 37.4%. The APACHE II and ISS scores of the non-survival group were significantly higher than those of the survival group [APACHE II score: 25.7±2.7 vs. 20.6±2.2, ISS score: 22.1±3.1 vs. 18.1±2.1, both P < 0.05]. EVLWI and Ang-2 showed a gradual downwards tendency with the prolongation of the length of ICU stay in the survival group, but no significant change was found in the non-survival group. Parallel contour test showed that both P < 0.05, indicating that the curves between the two groups had different tendencies and were not parallel. The levels of EVLWI, Ang-2 and PaO/FiO showed no statistical differences from 0 hour to 24 hours between the two groups, but EVLWI and Ang-2 in the non-survival group were significantly higher than those in the survival group from 48 hours on [EVLWI (mL/kg): 15.5±4.2 vs. 10.8±3.2, Ang-2 (ng/L): 352.7±51.2 vs. 237.9±42.8, both P < 0.05], and PaO/FiO was significantly decreased [mmHg (1 mmHg = 0.133 kPa): 126.1±43.7 vs. 211.2±33.8, P < 0.05]. The ΔEVLWI and ΔAng-2 in the non-survival group were significantly lower than those in the survival group [ΔEVLWI (mL/kg): -0.9±6.1 vs. 3.1±6.4, ΔAng-2 (ng/L): -45.3±32.1 vs. 79.8±58.2, both P < 0.05], but ΔPaO/FiO showed no significant difference as compared with the survival group (mmHg: 23.2±24.2 vs. -22.1±22.8, P > 0.05). Multivariate Logistic regression analysis demonstrated that ΔEVLWI [odds ratio (OR) = 2.811, 95% confidence interval (95%CI) = 1.232-3.161, P = 0.001], ΔAng-2 (OR = 2.204, 95%CI = 1.012-3.179, P = 0.001) and APACHE II (OR = 1.206, 95%CI = 1.102-1.683, P = 0.002) were independent risk factors for 28-day mortality of severe multiple trauma patients with ARDS. ROC curve analysis showed that the area under ROC curve (AUC) of ΔEVLWI for predicting 28-day prognosis of severe multiple trauma patients with ARDS was 0.832, which was higher than ΔAng-2 (AUC = 0.790) and APACHE II (AUC = 0.735). When the cut-off value of ΔEVLWI was 2.3 mL/kg, the sensitivity was 79.1%, and the specificity was 81.9%. Kaplan-Meier survival curve showed that the patients with ΔEVLWI > 2.3 mL/kg had a significantly higher 28-day cumulative survival rate as compared with the patients with ΔEVLWI ≤ 2.3 mL/kg (log-rank test: χ = 23.385, P = 0.000).

Conclusions: ΔEVLWI and ΔAng-2 can be used as independent risk factors for 28-day mortality of severe multiple trauma patients with ARDS, and the predictive value of ΔEVLWI was better than Ang-2 and APACHE II. Dynamic observation of EVLWI could improve the accuracy of death forecasting for severe multiple trauma patients with ARDS.