Analysis of risk factors and pathogenic bacteria of ventilator-associated pneumonia in patients with severe trauma undergoing mechanical ventilation in intensive care unit

Objective  To explore the risk factors and pathogen distribution of ventilator-associated pneumonia (VAP) in severe trauma patients undergoing mechanical ventilation in the intensive care unit (ICU).

Methods  A retrospective analysis of medical records of 142 severe trauma patients with mechanical ventilation in ICU was performed, and were divided into VAP group (56 cases) and non-VAP group (86 cases) according to whether VAP occurred. The clinical data such as gender, age, underlying diseases, diabetes history, past history of chronic obstructive pulmonary disease (COPD), smoking history, nasal feeding method, tracheotomy, hypoproteinemia, glucocorticoid use time, mechanical ventilation time, injury severity score (ISS) were compared. Multivariate regression was used to analyze the risk factors of VAP and the distribution characteristics of pathogenic bacteria in VAP patients were analyzed.

Results  Univariate analysis showed that proportions of age>60 years, underlying diseases>2 types, history of diabetes, previous history of COPD, nasogastric tube feeding, hypoproteinemia, ISS ≥16 in the VAP group were higher than those in the non-VAP group (P < 0.05). Multiple logistic regression analysis showed that the proportions of patients aged >60 years, with history of diabetes, nasogastric tube feeding, hypoproteinemia, ISS score ≥16 were independent risk factors for VAP in ICU mechanical ventilation patients. A total of 69 pathogenic bacteria were cultured in the sputum of 56 patients with VAP, of which 78.26% were Gram-negative bacteria, and 17.39% were Gram-positive bacteria, and 4.35% were fungi.

Conclusion  Risk factors for VAP include age >60 years, history of diabetes, nasogastric tube feeding, hypoproteinemia, ISS ≥16. Among them, Gram-negative bacteria is the main pathogen of VAP infection.