Predictive value of α-amylase in tracheal aspirates for ventilator-associated pneumonia in elderly patients

Objective: This study aims to investigate the correlation between α-amylase in tracheal aspirates and risk factors of aspiration, as well as ventilator-associated pneumonia (VAP), in elderly patients undergoing mechanical ventilation; and explore the clinical value of α-amylase for predicting VAP. Methods: Tracheal aspirates were collected from elderly patients within two weeks after tracheal intubation in mechanical ventilation, and α-amylase was detected. Patients were grouped according to the presence of VAP. The correlation between α-amylase and risk factors of aspiration before intubation, as well as VAP, were analyzed. Results: The sample of this study was comprised of 147 patients. The average age of these patients was 86.9 years old. The incidence of VAP was 21% during the study period. Tracheal aspirate α-amylase level increased with the increase in the number of risk factors for aspiration before intubation, α-amylase level was significantly higher in the VAP group than in the non-VAP group, the area under the receiver operating characteristic curve (ROC) of the diagnostic value of α-amylase for VAP was 0.813 (95% CI: 0.721-0.896), threshold value was 4,681.5 U/L, sensitivity was 0.801, and specificity was 0.793. Logistic multivariate analysis revealed the following risk factors for VAP: a number of risk factors before intubation of ≥3, a Glasgow score of 4,681.5 U/L. Conclusion: Tracheal aspirate α-amylase can serve as a biomarker for predicting VAP in elderly patients undergoing mechanical ventilation. This article is protected by copyright. All rights reserved.