Background: Aspiration of stomach content or saliva in critical conditions-e.g., shock,
intoxication, or resuscitation-can lead to acute lung injury. While various biomarkers
in bronchoalveolar lavage fluids have been studied for diagnosing aspiration, none
have been conclusively established as early indicators of lung damage. This study
aims to evaluate the diagnostic value of pepsin, bile acid, and other biomarkers for
detecting aspiration in an intensive care unit (ICU). Materials and methods: In this
study, 50 ICU patients were enrolled and underwent intubation before admission. The
evaluation of aspiration was based on clinical suspicion or documented instances of
observed events. Tracheal secretion (TS) samples were collected within 6 h after intubation
using sterile suction catheters. Additional parameters, including IL-6, pepsin, and
bile acid, were determined for analysis. Pepsin levels were measured with an ELISA
kit, while bile acid, uric acid, glucose, IL-6, and pH value in the tracheal secretion
were analyzed using standardized lab methods. Results: The 50 patients admitted to
the ICU with various diagnoses. The median survival time for the entire cohort was
52 days, and there was no significant difference in survival between patients with
aspiration pneumonia (AP) and those with other diagnoses (p = 0.69). Among the AP
group, the average survival time was 50.51 days (+/- 8.1 SD; 95% CI 34.63-66.39),
while patients with other diagnoses had a mean survival time of 32.86 days (+/- 5.1
SD; 95% CI 22.9-42.81); the survival group comparison did not yield statistically
significant results. The presence of pepsin or bile acid in TS patients did not significantly
impact survival or the diagnosis of aspiration. The p-values for the correlations
between pepsin and bile acid with the aspiration diagnosis were p = 0.53 and p > 0.99,
respectively; thus, pepsin and bile acid measurements did not significantly affect
survival outcomes or enhance the accuracy of diagnosing aspiration pneumonia. Conclusions:
The early and accurate diagnosis of aspiration is crucial for optimal patient care.
However, based on this study, pepsin concentration alone may not reliably indicate
aspiration, and bile acid levels also show limited association with the diagnosis.
Further validation studies are needed to assess the clinical usefulness and reliability
of gastric biomarkers in diagnosing aspiration-related conditions. Such future studies
would provide valuable insights for improving aspiration diagnosis and enhancing patient
care.
