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A pilot study of pepsin in tracheal and oral secretions
Marilyn Schallom1, Sally M Tricomi, Yie-Hwa Chang
1Barnes-Jewish Hospital, St Louis, MO 63108, USA. mes4143@bjc.org
Insights
Pepsin, a marker of gastric reflux, was detected in 20% of oral secretions and 4% of tracheal secretions from mechanically ventilated patients. This suggests pepsin in oral secretions may indicate aspiration risk.
Area of Science:
- Gastroenterology
- Pulmonology
- Critical Care Medicine
Background:
- Gastric reflux into the oropharynx precedes lung aspiration.
- Detecting pepsin in oral secretions may predict aspiration risk noninvasively.
Purpose of the Study:
- To determine the incidence of pepsin in oral and tracheal secretions.
- To assess pepsin presence in 50 gastric-fed, mechanically ventilated patients.
Main Methods:
- Exploratory descriptive study in 4 ICUs.
- Concurrent oral and tracheal secretion collection from 50 patients.
- Pepsin detection using Western blot analysis.
Main Results:
- Pepsin found in 20% of oral secretions (10/50 patients).
- Pepsin found in 4% of tracheal secretions (2/50 patients).
- Tracheal pepsin presence correlated with oral pepsin presence.
Conclusions:
- Pepsin is detected more frequently in oral than tracheal secretions.
- Pepsin in oral secretions may indicate elevated aspiration risk.
- Reflux does not always equate to aspiration.
Background:
Because reflux of gastric juice into the oropharynx must precede its aspiration into the lungs, it is reasonable to hypothesize that the detection of pepsin (the major gastric enzyme in gastric juice) in oral secretions may provide a relatively noninvasive method of predicting risk for aspiration.
Objective:
To describe the incidence of pepsin in oral and tracheal secretions collected concurrently from a sample of 50 gastric-fed patients undergoing mechanical ventilation.
Methods:
An exploratory descriptive design with a convenience sample from 4 medical and surgical intensive care units. An oral secretion and a tracheal secretion were collected concurrently from each patient (yielding a sample of 50 oral and 50 tracheal secretions). The tracheal secretions were obtained via the inline suction system with an attached sputum trap; oral secretions were obtained via a Yankauer suction tip with an attached sputum trap. All specimens were assayed for pepsin by the Western blot method.
Results:
Oral secretions from 10 patients (20%) and tracheal secretions from 2 patients (4%) were pepsin-positive. Both patients with pepsin-positive tracheal secretions also had pepsin-positive oral secretions. Pepsin was not found in the tracheal secretions from the remaining 8 patients with pepsin-positive oral secretions.
Conclusions:
Although reflux of gastric juice into the oropharynx must precede its aspiration into the lungs, individual reflux events do not necessarily lead to aspiration. Thus, it is reasonable that we found pepsin 5 times more often in oral secretions than in tracheal secretions.
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