Objective:To investigate the distribution of pathogens and changes in serum levels of pyruvate kinase isozyme type M2 (PKM2) and Galectin-3 in patients with severe trauma complicated by ventilator-associated pneumonia (VAP).Methods:A total of 139 patients with severe trauma and underwent mechanical ventilation in Zhangjiakou First Hospital from February 2022 to February 2024 were selected as the study subjects. They were divided into the VAP group (57 cases) and non- VAP group (82 cases) based on whether they developed VAP. The distribution of pathogenic bacteria in the VAP group was analyzed. Enzyme-linked immunosorbent assay (ELISA) method was applied to determine the expression levels of serum PKM2 and Galectin-3. Multivariate Logistic regression was applied to analyze the influencing factors of VAP in patients with severe trauma. Receiver operator characteristic (ROC) curve was applied to analyze the diagnostic value of serum PKM2 and Galectin-3 levels for severe trauma complicated by VAP.Results:Seventy-one strains of pathogenic bacteria were isolated from 57 patients in the VAP group, mainly including Gram positive bacteria (36.62%), Gram negative bacteria (59.15%), and fungi (4.23%). Among them, Gram positive bacteria were mainly Staphylococcus epidermidis and Staphylococcus aureus, Gram negative bacteria were mainly Acinetobacter baumannii and Klebsiella pneumoniae, and fungi were mainly tropical Candida and Candida albicans. The proportion of history of diabetes, the proportion of eating through nasogastric tube, the proportion of trauma severity score ≥ 16 and the levels of serum PKM2 and Galectin-3 in the VAP group were higher than those in the non- VAP group: 54.39%(31/57) vs. 32.93%(27/82), 82.46%(47/57) vs. 52.44%(43/82), 66.67%(38/57) vs. 24.39%(20/82), (32.46 ± 7.28) μg/L vs. (24.25 ± 6.17) μg/L, (3.26 ± 0.75) ng/L vs. (2.39 ± 0.61) ng/L, there were statistical differences ( P<0.05). Serum PKM2, Galectin-3, history of diabetes, nasal feeding mode and trauma severity score were the influencing factors of severe trauma patients complicated by VAP ( P<0.05). The area under the curve (AUC) of serum PKM2, Galectin-3, and their combination in predicting severe trauma complicated by VAP was 0.90, and the combination of the two was superior to their respective individual diagnoses ( Zcombination - PKM2 = 2.00, Zcombination - Galectin-3 = 1.99, P = 0.046, 0.047), its sensitivity and specificity were 92.98% and 84.15%, respectively. Conclusions:The distribution of urinary tract pathogens in patients with severe trauma complicated by VAP is mainly Gram negative bacteria, and serum PKM2 and Galectin-3 levels are obviously increased in patients with severe trauma complicated by VAP . The combination of the two has higher diagnostic value for severe trauma complicated by VAP and certain clinical application value.

Objective:To investigate the distribution of pathogens and changes in serum levels of pyruvate kinase isozyme type M2 (PKM2) and Galectin-3 in patients with severe trauma complicated by ventilator-associated pneumonia (VAP).Methods:A total of 139 patients with severe trauma and underwent mechanical ventilation in Zhangjiakou First Hospital from February 2022 to February 2024 were selected as the study subjects. They were divided into the VAP group (57 cases) and non- VAP group (82 cases) based on whether they developed VAP. The distribution of pathogenic bacteria in the VAP group was analyzed. Enzyme-linked immunosorbent assay (ELISA) method was applied to determine the expression levels of serum PKM2 and Galectin-3. Multivariate Logistic regression was applied to analyze the influencing factors of VAP in patients with severe trauma. Receiver operator characteristic (ROC) curve was applied to analyze the diagnostic value of serum PKM2 and Galectin-3 levels for severe trauma complicated by VAP.Results:Seventy-one strains of pathogenic bacteria were isolated from 57 patients in the VAP group, mainly including Gram positive bacteria (36.62%), Gram negative bacteria (59.15%), and fungi (4.23%). Among them, Gram positive bacteria were mainly Staphylococcus epidermidis and Staphylococcus aureus, Gram negative bacteria were mainly Acinetobacter baumannii and Klebsiella pneumoniae, and fungi were mainly tropical Candida and Candida albicans. The proportion of history of diabetes, the proportion of eating through nasogastric tube, the proportion of trauma severity score ≥ 16 and the levels of serum PKM2 and Galectin-3 in the VAP group were higher than those in the non- VAP group: 54.39%(31/57) vs. 32.93%(27/82), 82.46%(47/57) vs. 52.44%(43/82), 66.67%(38/57) vs. 24.39%(20/82), (32.46 ± 7.28) μg/L vs. (24.25 ± 6.17) μg/L, (3.26 ± 0.75) ng/L vs. (2.39 ± 0.61) ng/L, there were statistical differences ( P<0.05). Serum PKM2, Galectin-3, history of diabetes, nasal feeding mode and trauma severity score were the influencing factors of severe trauma patients complicated by VAP ( P<0.05). The area under the curve (AUC) of serum PKM2, Galectin-3, and their combination in predicting severe trauma complicated by VAP was 0.90, and the combination of the two was superior to their respective individual diagnoses ( Zcombination - PKM2 = 2.00, Zcombination - Galectin-3 = 1.99, P = 0.046, 0.047), its sensitivity and specificity were 92.98% and 84.15%, respectively. Conclusions:The distribution of urinary tract pathogens in patients with severe trauma complicated by VAP is mainly Gram negative bacteria, and serum PKM2 and Galectin-3 levels are obviously increased in patients with severe trauma complicated by VAP . The combination of the two has higher diagnostic value for severe trauma complicated by VAP and certain clinical application value.