Detecting Enteral Nutrition Residues and Microorganism Proliferation in Feeding Tubes via Real‐Time Imaging

Background:
Enteral nutrition (EN) residues that persist in feeding tubes provide substrates for microorganisms to proliferate and occlude the tubes. Visible EN residues in tubes are easily identified, but smaller residues can persist. We developed a new imaging technique to visualize EN residues and proliferation of microorganisms in feeding tubes.
Materials and Methods:
Feeding tubes containing EN labelled with fluorescent dye and EN with or without various types or amounts of thickeners were flushed once with water and then the tubes were seeded with Pseudomonas aeruginosa Xen5 with recombinant luciferase DNA. Because EN fluoresces intrinsically, EN in the feeding tubes without fluorescent dye was repeatedly flushed until the intrinsic fluorescence levels reached background levels. Fluorescent images of EN residues and bioluminescent images of microorganisms were acquired using an optical imaging system.
Results:
Fluorescence images showed that the amount of EN residues increased at various sites in tubes depending on EN viscosity and the thickening agent, and bioluminescence images showed that microorganism proliferation was associated with a commensurate increase in EN residues. The intrinsic fluorescence of EN also enabled the detection of EN residues in tubes even in the absence of fluorescence dye. Higher EN viscosity required more flushes to reach undetectable levels.
Conclusion:
EN residues and microorganism proliferation in enteral feeding tubes were detected on fluorescence and bioluminescence images, respectively. This simplified approach allowed the real-time visualization of EN residues and microorganisms in feeding tubes.

内容要旨・審査要旨・論文本文の公開
本論文は, 著者Ippei Yamaokaの学位論文として提出され, 学位審査・授与の対象となっている。
This is the peer reviewed version of the following article: Yamaoka, I. , Kagawa, T. , Mizugai, K. and Ebisu, G. (2017), Detecting Enteral Nutrition Residues and Microorganism Proliferation in Feeding Tubes via Real‐Time Imaging. Nutrition in Clinical Practice, 32: 282-287, which has been published in final form at https://doi.org/10.1177/0884533616675189. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.