Tracheal amylase dosage as a marker for microaspiration: a pilot study

Area of Science:

• Critical Care Medicine
• Pulmonology
• Biochemistry

Background:

• Ventilator-associated pneumonia (VAP) is a concern in intubated patients.
• Devices limiting microaspiration may prevent VAP.
• Tracheal microaspiration quantification is a potential study endpoint.

Purpose of the Study:

• To evaluate amylase in tracheal secretions as a marker for microaspiration.
• To compare tracheal amylase levels between high-risk and low-risk microaspiration groups.

Main Methods:

• Studied 26 intubated patients (high-risk) and 12 non-ventilated patients (control).
• Collected tracheal, subglottic, and oral suction samples.
• Measured amylase levels and calculated tracheal/oral (T/O) and tracheal/subglottic (T/Sg) ratios.

Main Results:

• Tracheal amylase was significantly higher in intubated patients (6661 IU/L) than controls (191 IU/L).
• Amylase levels increased from tracheal to subglottic to oral samples.
• A median T/O amylase ratio of 5.5% was observed, with reproducible laboratory results.

Conclusions:

• Tracheal amylase is an easily measurable marker for microaspiration.
• The T/O amylase ratio aids in quantifying oropharyngeal to tracheal microaspiration.
• This marker could improve VAP prevention strategies.