{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T17:13:34Z","timestamp":1770743614288,"version":"3.49.0"},"reference-count":25,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2020,10,28]],"date-time":"2020-10-28T00:00:00Z","timestamp":1603843200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100016156","name":"U.S. Army Medical Research and Development Command","doi-asserted-by":"publisher","award":["D_003_2017_USAISR"],"award-info":[{"award-number":["D_003_2017_USAISR"]}],"id":[{"id":"10.13039\/100016156","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Endotracheal intubation is a common life-saving procedure implemented in emergency care to ensure patient oxygenation, but it is difficult and often performed in suboptimal conditions leading to high rates of patient complications. Undetected misplacement in the esophagus is a preventable complication that can lead to fatalities in 5\u201310% of patients who undergo emergency intubation. End-tidal carbon dioxide monitoring and other proper placement detection methods are useful, yet the problem of misplacement persists. Our previous work demonstrated the utility of spectral reflectance sensors for differentiating esophageal and tracheal tissues, which can be used to confirm proper endotracheal tube placement. In this study, we examine the effectiveness of spectral characterization in the presence of saline, blood, \u201cvomit\u201d, and soot in the trachea. Our results show that spectral properties of the trachea that differentiate it from the esophagus persist in the presence of these substances. This work further confirms the potential usefulness of this novel detection technology in field applications.<\/jats:p>","DOI":"10.3390\/s20216138","type":"journal-article","created":{"date-parts":[[2020,10,29]],"date-time":"2020-10-29T21:21:00Z","timestamp":1604006460000},"page":"6138","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Spectral Reflectance Can Differentiate Tracheal and Esophageal Tissue in the Presence of Bodily Fluids and Soot"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2286-3846","authenticated-orcid":false,"given":"David","family":"Berard","sequence":"first","affiliation":[{"name":"Tactical Combat Casualty Care Research Department, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX 78234, USA"},{"name":"Department of Mechanical Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chirantan","family":"Sen","sequence":"additional","affiliation":[{"name":"Tactical Combat Casualty Care Research Department, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX 78234, USA"},{"name":"Department of Electrical and Computer Engineering, Mississippi State University, Mississippi State, MS 39762, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Corinne D.","family":"Nawn","sequence":"additional","affiliation":[{"name":"Tactical Combat Casualty Care Research Department, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX 78234, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"August N.","family":"Blackburn","sequence":"additional","affiliation":[{"name":"Blackburn Statistics, LLC, San Antonio, TX 78260, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kathy L.","family":"Ryan","sequence":"additional","affiliation":[{"name":"Tactical Combat Casualty Care Research Department, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX 78234, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Megan B.","family":"Blackburn","sequence":"additional","affiliation":[{"name":"Tactical Combat Casualty Care Research Department, US Army Institute of Surgical Research, JBSA Fort Sam Houston, TX 78234, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"781","DOI":"10.1136\/emermed-2013-203473","article-title":"Repeated attempts at tracheal intubation by a single intubator associated with decreased success rates in emergency departments: An analysis of a multicentre prospective observational study","volume":"32","author":"Goto","year":"2015","journal-title":"Emerg. 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